From 5d709bded501b0688d3b798f121f0bbabbd46846 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Thu, 26 Mar 2020 00:53:04 +0530
Subject: [PATCH 01/16] Remove i32 conversion from fzf helper

---
 src/util.rs | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/util.rs b/src/util.rs
index c223a96..53d016b 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -45,15 +45,8 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
 
     for dir in dirs.iter() {
         // ensure that frecency fits in 4 characters
-        let frecency = if dir.rank > 9999.0 {
-            9999
-        } else if dir.rank > 0.0 {
-            dir.rank as i32
-        } else {
-            0
-        };
-
-        writeln!(fzf_stdin, "{:>4}        {}", frecency, dir.path)
+        let frecency = clamp(dir.rank, 0.0, 9999.0);
+        writeln!(fzf_stdin, "{:>4.0}        {}", frecency, dir.path)
             .with_context(|| anyhow!("could not write into fzf stdin"))?;
     }
 
@@ -89,3 +82,18 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
         _ => bail!("fzf returned an unknown error"),
     }
 }
+
+// FIXME: replace with f64::clamp once it is stable <https://github.com/rust-lang/rust/issues/44095>
+#[must_use = "method returns a new number and does not mutate the original value"]
+#[inline]
+pub fn clamp(val: f64, min: f64, max: f64) -> f64 {
+    assert!(min <= max);
+    let mut x = val;
+    if x < min {
+        x = min;
+    }
+    if x > max {
+        x = max;
+    }
+    x
+}

From 857e15c65f383a6a41707712e8ccb4641ae28d2d Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Thu, 26 Mar 2020 01:13:14 +0530
Subject: [PATCH 02/16] Remove conversion to i64 when sorting

---
 src/util.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/util.rs b/src/util.rs
index 53d016b..e4a537f 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -3,6 +3,7 @@ use crate::dir::Dir;
 use crate::env::Env;
 use crate::types::Epoch;
 use anyhow::{anyhow, bail, Context, Result};
+use std::cmp::{Ordering, PartialOrd};
 use std::io::{Read, Write};
 use std::process::{Command, Stdio};
 use std::time::SystemTime;
@@ -41,7 +42,12 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
         dir.rank = dir.get_frecency(now);
     }
 
-    dirs.sort_by_key(|dir| std::cmp::Reverse(dir.rank as i64));
+    dirs.sort_unstable_by(|dir1, dir2| {
+        dir1.rank
+            .partial_cmp(&dir2.rank)
+            .unwrap_or(Ordering::Equal)
+            .reverse()
+    });
 
     for dir in dirs.iter() {
         // ensure that frecency fits in 4 characters

From 890185176e14510d420c1e484c024d1bc5038141 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Fri, 27 Mar 2020 17:11:26 +0530
Subject: [PATCH 03/16] Store paths as PathBuf rather than String

---
 Cargo.lock                | 135 ++++++++++++++++++++++++++++----------
 Cargo.toml                |  10 ++-
 src/db.rs                 |  82 +++++++++--------------
 src/dir.rs                |  41 ++++++++----
 src/main.rs               |   3 +-
 src/subcommand/add.rs     |   7 +-
 src/subcommand/migrate.rs |   1 +
 src/subcommand/query.rs   |  31 ++++++---
 src/subcommand/remove.rs  |   1 +
 src/util.rs               |  43 ++++++++----
 10 files changed, 223 insertions(+), 131 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 1c8ebbe..7e40c16 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -10,7 +10,7 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.26"
+version = "1.0.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -29,7 +29,7 @@ version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -49,7 +49,7 @@ version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -67,6 +67,16 @@ dependencies = [
  "constant_time_eq 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "bstr"
+version = "0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-automata 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "byteorder"
 version = "1.3.4"
@@ -121,7 +131,7 @@ version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
  "redox_users 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -131,7 +141,7 @@ name = "envy"
 version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -140,7 +150,7 @@ version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
  "wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -157,7 +167,28 @@ name = "hermit-abi"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "indoc"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "indoc-impl 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "indoc-impl"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unindent 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -167,33 +198,43 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "libc"
-version = "0.2.67"
+version = "0.2.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "memchr"
+version = "2.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "proc-macro-error"
-version = "0.4.11"
+version = "0.4.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "proc-macro-error-attr 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "proc-macro-error-attr"
-version = "0.4.11"
+version = "0.4.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "syn-mid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "proc-macro-hack"
+version = "0.5.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.9"
@@ -225,6 +266,14 @@ dependencies = [
  "rust-argon2 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "regex-automata"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rust-argon2"
 version = "0.7.0"
@@ -238,20 +287,20 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.104"
+version = "1.0.105"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "serde_derive 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.104"
+version = "1.0.105"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -261,29 +310,29 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "structopt"
-version = "0.3.11"
+version = "0.3.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt-derive 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt-derive 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "structopt-derive"
-version = "0.4.4"
+version = "0.4.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro-error 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "syn"
-version = "1.0.16"
+version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -298,7 +347,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
  "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)",
+ "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -324,6 +373,11 @@ name = "unicode-xid"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "unindent"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "vec_map"
 version = "0.8.1"
@@ -362,18 +416,20 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "zoxide"
 version = "0.2.2"
 dependencies = [
- "anyhow 1.0.26 (registry+https://github.com/rust-lang/crates.io-index)",
+ "anyhow 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "bincode 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bstr 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "envy 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "serde 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)",
- "structopt 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
+ "structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [metadata]
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
-"checksum anyhow 1.0.26 (registry+https://github.com/rust-lang/crates.io-index)" = "7825f6833612eb2414095684fcf6c635becf3ce97fe48cf6421321e93bfbd53c"
+"checksum anyhow 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)" = "013a6e0a2cbe3d20f9c60b65458f7a7f7a5e636c5d0f45a5a6aee5d4b1f01785"
 "checksum arrayref 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "a4c527152e37cf757a3f78aae5a06fbeefdb07ccc535c980a3208ee3060dd544"
 "checksum arrayvec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cff77d8686867eceff3105329d4698d96c2391c176d5d03adc90c7389162b5b8"
 "checksum atty 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "d9b39be18770d11421cdb1b9947a45dd3f37e93092cbf377614828a319d5fee8"
@@ -382,6 +438,7 @@ dependencies = [
 "checksum bincode 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5753e2a71534719bf3f4e57006c3a4f0d2c672a4b676eec84161f763eca87dbf"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 "checksum blake2b_simd 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)" = "d8fb2d74254a3a0b5cac33ac9f8ed0e44aa50378d9dbb2e5d83bd21ed1dc2c8a"
+"checksum bstr 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)" = "2889e6d50f394968c8bf4240dc3f2a7eb4680844d27308f798229ac9d4725f41"
 "checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 "checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 "checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
@@ -393,26 +450,32 @@ dependencies = [
 "checksum getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
 "checksum heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "20564e78d53d2bb135c343b3f47714a56af2061f1c928fdb541dc7b9fdd94205"
 "checksum hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "1010591b26bbfe835e9faeabeb11866061cc7dcebffd56ad7d0942d0e61aefd8"
+"checksum indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "79255cf29f5711995ddf9ec261b4057b1deb34e66c90656c201e41376872c544"
+"checksum indoc-impl 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "54554010aa3d17754e484005ea0022f1c93839aabc627c2c55f3d7b47206134c"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
-"checksum libc 0.2.67 (registry+https://github.com/rust-lang/crates.io-index)" = "eb147597cdf94ed43ab7a9038716637d2d1bf2bc571da995d0028dec06bd3018"
-"checksum proc-macro-error 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)" = "e7959c6467d962050d639361f7703b2051c43036d03493c36f01d440fdd3138a"
-"checksum proc-macro-error-attr 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)" = "e4002d9f55991d5e019fb940a90e1a95eb80c24e77cb2462dd4dc869604d543a"
+"checksum libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)" = "dea0c0405123bba743ee3f91f49b1c7cfb684eef0da0a50110f758ccf24cdff0"
+"checksum memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
+"checksum proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "18f33027081eba0a6d8aba6d1b1c3a3be58cbb12106341c2d5759fcd9b5277e7"
+"checksum proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "8a5b4b77fdb63c1eca72173d68d24501c54ab1269409f6b672c85deb18af69de"
+"checksum proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)" = "fcfdefadc3d57ca21cf17990a28ef4c0f7c61383a28cb7604cf4a18e6ede1420"
 "checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 "checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
 "checksum redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)" = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
 "checksum redox_users 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "09b23093265f8d200fa7b4c2c76297f47e681c655f6f1285a8780d6a022f7431"
+"checksum regex-automata 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "ae1ded71d66a4a97f5e961fd0cb25a5f366a42a41570d16a763a69c092c26ae4"
 "checksum rust-argon2 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2bc8af4bda8e1ff4932523b94d3dd20ee30a87232323eda55903ffd71d2fb017"
-"checksum serde 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)" = "414115f25f818d7dfccec8ee535d76949ae78584fc4f79a6f45a904bf8ab4449"
-"checksum serde_derive 1.0.104 (registry+https://github.com/rust-lang/crates.io-index)" = "128f9e303a5a29922045a830221b8f78ec74a5f544944f3d5984f8ec3895ef64"
+"checksum serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)" = "e707fbbf255b8fc8c3b99abb91e7257a622caeb20a9818cbadbeeede4e0932ff"
+"checksum serde_derive 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)" = "ac5d00fc561ba2724df6758a17de23df5914f20e41cb00f94d5b7ae42fffaff8"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
-"checksum structopt 0.3.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3fe43617218c0805c6eb37160119dc3c548110a67786da7218d1c6555212f073"
-"checksum structopt-derive 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "c6e79c80e0f4efd86ca960218d4e056249be189ff1c42824dcd9a7f51a56f0bd"
-"checksum syn 1.0.16 (registry+https://github.com/rust-lang/crates.io-index)" = "123bd9499cfb380418d509322d7a6d52e5315f064fe4b3ad18a53d6b92c07859"
+"checksum structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)" = "c8faa2719539bbe9d77869bfb15d4ee769f99525e707931452c97b693b3f159d"
+"checksum structopt-derive 0.4.5 (registry+https://github.com/rust-lang/crates.io-index)" = "3f88b8e18c69496aad6f9ddf4630dd7d585bcaf765786cb415b9aec2fe5a0430"
+"checksum syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)" = "0df0eb663f387145cab623dea85b09c2c5b4b0aef44e945d928e682fce71bb03"
 "checksum syn-mid 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7be3539f6c128a931cf19dcee741c1af532c7fd387baa739c03dd2e96479338a"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
 "checksum unicode-segmentation 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e83e153d1053cbb5a118eeff7fd5be06ed99153f00dbcd8ae310c5fb2b22edc0"
 "checksum unicode-width 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
 "checksum unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
+"checksum unindent 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "63f18aa3b0e35fed5a0048f029558b1518095ffe2a0a31fb87c93dece93a4993"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
 "checksum wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)" = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
diff --git a/Cargo.toml b/Cargo.toml
index 40d270c..e31e3a3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,13 +13,17 @@ license = "MIT"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-anyhow = "1.0.26"
+anyhow = "1.0.27"
 bincode = "1.2.1"
 clap = "2.33.0"
 dirs = "2.0.2"
 envy = "0.4.1"
-serde = { version = "1.0.104", features = ["derive"] }
-structopt = "0.3.11"
+indoc = "0.3.5"
+serde = { version = "1.0.105", features = ["derive"] }
+structopt = "0.3.12"
+
+[target.'cfg(unix)'.dependencies]
+bstr = "0.2.12"
 
 [profile.release]
 codegen-units = 1
diff --git a/src/db.rs b/src/db.rs
index 6e5badb..a3806a0 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -1,6 +1,8 @@
 use crate::dir::Dir;
 use crate::types::{Epoch, Rank};
+
 use anyhow::{anyhow, bail, Context, Result};
+use indoc::indoc;
 use std::fs::{self, File};
 use std::io::{self, BufRead, BufReader, BufWriter};
 use std::path::{Path, PathBuf};
@@ -18,12 +20,11 @@ impl DB {
         let dirs = match File::open(&path) {
             Ok(file) => {
                 let reader = BufReader::new(&file);
-                bincode::deserialize_from(reader)
-                    .with_context(|| anyhow!("could not deserialize database"))?
+                bincode::deserialize_from(reader).context("could not deserialize database")?
             }
             Err(err) => match err.kind() {
                 io::ErrorKind::NotFound => Vec::<Dir>::new(),
-                _ => return Err(err).with_context(|| anyhow!("could not open database file")),
+                _ => return Err(err).context("could not open database file"),
             },
         };
 
@@ -38,15 +39,13 @@ impl DB {
         if self.modified {
             let path_tmp = self.get_path_tmp();
 
-            let file_tmp = File::create(&path_tmp)
-                .with_context(|| anyhow!("could not open temporary database file"))?;
+            let file_tmp =
+                File::create(&path_tmp).context("could not open temporary database file")?;
 
             let writer = BufWriter::new(&file_tmp);
-            bincode::serialize_into(writer, &self.dirs)
-                .with_context(|| anyhow!("could not serialize database"))?;
+            bincode::serialize_into(writer, &self.dirs).context("could not serialize database")?;
 
-            fs::rename(&path_tmp, &self.path)
-                .with_context(|| anyhow!("could not move temporary database file"))?;
+            fs::rename(&path_tmp, &self.path).context("could not move temporary database file")?;
         }
 
         Ok(())
@@ -54,14 +53,13 @@ impl DB {
 
     pub fn migrate<P: AsRef<Path>>(&mut self, path: P, merge: bool) -> Result<()> {
         if !self.dirs.is_empty() && !merge {
-            bail!(
+            bail!(indoc!(
                 "To prevent conflicts, you can only migrate from z with an empty zoxide database!
-If you wish to merge the two, specify the `--merge` flag."
-            );
+                If you wish to merge the two, specify the `--merge` flag."
+            ));
         }
 
-        let z_db_file =
-            File::open(path).with_context(|| anyhow!("could not open z database file"))?;
+        let z_db_file = File::open(path).context("could not open z database file")?;
         let reader = BufReader::new(z_db_file);
 
         for (idx, read_line) in reader.lines().enumerate() {
@@ -104,22 +102,11 @@ If you wish to merge the two, specify the `--merge` flag."
                             continue;
                         }
                     };
-                    let path_str = match path_abs.to_str() {
-                        Some(path) => path,
-                        None => {
-                            eprintln!(
-                                "invalid unicode in path '{}' at line {}",
-                                path_abs.display(),
-                                line_number
-                            );
-                            continue;
-                        }
-                    };
 
                     if merge {
                         // If the path exists in the database, add the ranks and set the epoch to
                         // the largest of the parsed epoch and the already present epoch.
-                        if let Some(dir) = self.dirs.iter_mut().find(|dir| dir.path == path_str) {
+                        if let Some(dir) = self.dirs.iter_mut().find(|dir| dir.path == path_abs) {
                             dir.rank += rank;
                             dir.last_accessed = Epoch::max(epoch, dir.last_accessed);
 
@@ -130,7 +117,7 @@ If you wish to merge the two, specify the `--merge` flag."
                     // FIXME: When we switch to PathBuf for storing directories inside Dir, just
                     // pass `PathBuf::from(path_str)`
                     self.dirs.push(Dir {
-                        path: path_str.to_string(),
+                        path: path_abs,
                         rank,
                         last_accessed: epoch,
                     });
@@ -154,13 +141,9 @@ If you wish to merge the two, specify the `--merge` flag."
             .canonicalize()
             .with_context(|| anyhow!("could not access directory: {}", path.as_ref().display()))?;
 
-        let path_str = path_abs
-            .to_str()
-            .ok_or_else(|| anyhow!("invalid unicode in path: {}", path_abs.display()))?;
-
-        match self.dirs.iter_mut().find(|dir| dir.path == path_str) {
+        match self.dirs.iter_mut().find(|dir| dir.path == path_abs) {
             None => self.dirs.push(Dir {
-                path: path_str.to_string(),
+                path: path_abs,
                 last_accessed: now,
                 rank: 1.0,
             }),
@@ -186,20 +169,19 @@ If you wish to merge the two, specify the `--merge` flag."
     }
 
     pub fn query(&mut self, keywords: &[String], now: Epoch) -> Option<Dir> {
-        loop {
-            let (idx, dir) = self
-                .dirs
-                .iter()
-                .enumerate()
-                .filter(|(_, dir)| dir.is_match(keywords))
-                .max_by_key(|(_, dir)| dir.get_frecency(now) as i64)?;
+        let (idx, dir) = self
+            .dirs
+            .iter()
+            .enumerate()
+            .filter(|(_, dir)| dir.is_match(&keywords))
+            .max_by_key(|(_, dir)| dir.get_frecency(now) as i64)?;
 
-            if dir.is_dir() {
-                return Some(dir.to_owned());
-            } else {
-                self.dirs.remove(idx);
-                self.modified = true;
-            }
+        if dir.is_dir() {
+            Some(dir.to_owned())
+        } else {
+            self.dirs.swap_remove(idx);
+            self.modified = true;
+            self.query(keywords, now)
         }
     }
 
@@ -219,12 +201,8 @@ If you wish to merge the two, specify the `--merge` flag."
             Err(_) => path.as_ref().to_path_buf(),
         };
 
-        let path_str = path_abs
-            .to_str()
-            .ok_or_else(|| anyhow!("invalid unicode in path"))?;
-
-        if let Some(idx) = self.dirs.iter().position(|dir| dir.path == path_str) {
-            self.dirs.remove(idx);
+        if let Some(idx) = self.dirs.iter().position(|dir| dir.path == path_abs) {
+            self.dirs.swap_remove(idx);
             self.modified = true;
         }
 
diff --git a/src/dir.rs b/src/dir.rs
index 5a5f97b..c24d74a 100644
--- a/src/dir.rs
+++ b/src/dir.rs
@@ -1,36 +1,49 @@
 use crate::types::{Epoch, Rank};
+
 use serde::{Deserialize, Serialize};
-use std::path::Path;
+use std::path::PathBuf;
 
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 pub struct Dir {
-    pub path: String,
+    pub path: PathBuf,
     pub rank: Rank,
     pub last_accessed: Epoch,
 }
 
 impl Dir {
     pub fn is_dir(&self) -> bool {
-        Path::new(&self.path).is_dir()
+        self.path.is_dir()
     }
 
+    #[cfg(unix)]
     pub fn is_match(&self, query: &[String]) -> bool {
-        let path = self.path.to_ascii_lowercase();
+        use bstr::ByteSlice;
+        use std::os::unix::ffi::OsStrExt;
 
-        if let Some(query_name) = query.last().and_then(|word| Path::new(word).file_name()) {
-            if let Some(path_name) = Path::new(&path).file_name() {
-                // `unwrap()` here should be safe because the values are already encoded as UTF-8
-                let query_name = query_name.to_str().unwrap();
-                let path_name = path_name.to_str().unwrap();
+        let path_bytes = self.path.as_os_str().as_bytes().to_lowercase();
+        let mut subpath = path_bytes.as_slice();
 
-                if !path_name.contains(&query_name) {
-                    return false;
-                }
+        for subquery in query.iter() {
+            let subquery_bytes = subquery.as_bytes();
+            match subpath.find(subquery_bytes) {
+                Some(idx) => subpath = &subpath[idx + subquery_bytes.len()..],
+                None => return false,
             }
         }
 
-        let mut subpath = path.as_str();
-        for subquery in query {
+        true
+    }
+
+    #[cfg(not(unix))]
+    pub fn is_match(&self, query: &[String]) -> bool {
+        let path_str = match self.path.to_str() {
+            Some(path_str) => path_str.to_lowercase(),
+            None => return false, // silently ignore invalid UTF-8
+        };
+
+        let mut subpath = path_str.as_str();
+
+        for subquery in query.iter() {
             match subpath.find(subquery) {
                 Some(idx) => subpath = &subpath[idx + subquery.len()..],
                 None => return false,
diff --git a/src/main.rs b/src/main.rs
index 8d64a43..de5d4c7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,6 +6,7 @@ mod types;
 mod util;
 
 use crate::env::Env;
+
 use anyhow::{Context, Result};
 use structopt::StructOpt;
 
@@ -23,7 +24,7 @@ pub fn main() -> Result<()> {
     let opt = Zoxide::from_args();
     let env = envy::prefixed("_ZO_")
         .from_env::<Env>()
-        .with_context(|| "could not parse environment variables")?;
+        .context("could not parse environment variables")?;
 
     match opt {
         Zoxide::Add(add) => add.run(&env)?,
diff --git a/src/subcommand/add.rs b/src/subcommand/add.rs
index 4904307..35160fb 100644
--- a/src/subcommand/add.rs
+++ b/src/subcommand/add.rs
@@ -1,7 +1,8 @@
 use crate::env::Env;
 use crate::types::Rank;
 use crate::util;
-use anyhow::{anyhow, Context, Result};
+
+use anyhow::{Context, Result};
 use std::env;
 use structopt::StructOpt;
 
@@ -20,8 +21,8 @@ impl Add {
         match &self.path {
             Some(path) => db.add(path, maxage, now),
             None => {
-                let current_dir = env::current_dir()
-                    .with_context(|| anyhow!("unable to fetch current directory"))?;
+                let current_dir =
+                    env::current_dir().context("unable to fetch current directory")?;
                 db.add(current_dir, maxage, now)
             }
         }
diff --git a/src/subcommand/migrate.rs b/src/subcommand/migrate.rs
index c3e67ec..55c5d45 100644
--- a/src/subcommand/migrate.rs
+++ b/src/subcommand/migrate.rs
@@ -1,5 +1,6 @@
 use crate::env::Env;
 use crate::util;
+
 use anyhow::Result;
 use structopt::StructOpt;
 
diff --git a/src/subcommand/query.rs b/src/subcommand/query.rs
index e5cc4f9..eea7c51 100644
--- a/src/subcommand/query.rs
+++ b/src/subcommand/query.rs
@@ -1,6 +1,8 @@
 use crate::env::Env;
 use crate::util;
+
 use anyhow::{bail, Result};
+use std::io::{self, Write};
 use std::path::Path;
 use structopt::StructOpt;
 
@@ -21,38 +23,47 @@ impl Query {
         };
 
         match path_opt {
-            Some(path) => println!("query: {}", path.trim()),
+            Some(path) => {
+                let stdout = io::stdout();
+                let mut handle = stdout.lock();
+                handle.write_all(b"query: ").unwrap();
+                handle.write_all(&path).unwrap();
+                handle.write_all(b"\n").unwrap();
+            }
             None => bail!("no match found"),
         };
 
         Ok(())
     }
 
-    fn query(&mut self, env: &Env) -> Result<Option<String>> {
+    fn query(&mut self, env: &Env) -> Result<Option<Vec<u8>>> {
         if let [path] = self.keywords.as_slice() {
             if Path::new(path).is_dir() {
-                return Ok(Some(path.to_string()));
+                return Ok(Some(path.as_bytes().to_vec()));
             }
         }
 
-        for keyword in &mut self.keywords {
-            keyword.make_ascii_lowercase();
-        }
-
         let now = util::get_current_time()?;
 
+        for keyword in &mut self.keywords {
+            *keyword = keyword.to_lowercase();
+        }
+
         if let Some(dir) = util::get_db(env)?.query(&self.keywords, now) {
-            Ok(Some(dir.path))
+            // `path_to_bytes` is guaranteed to succeed here since
+            // the path has already been queried successfully
+            let path_bytes = util::path_to_bytes(&dir.path).unwrap();
+            Ok(Some(path_bytes.to_vec()))
         } else {
             Ok(None)
         }
     }
 
-    fn query_interactive(&mut self, env: &Env) -> Result<Option<String>> {
+    fn query_interactive(&mut self, env: &Env) -> Result<Option<Vec<u8>>> {
         let now = util::get_current_time()?;
 
         for keyword in &mut self.keywords {
-            keyword.make_ascii_lowercase();
+            *keyword = keyword.to_lowercase();
         }
 
         let dirs = util::get_db(env)?.query_all(&self.keywords);
diff --git a/src/subcommand/remove.rs b/src/subcommand/remove.rs
index 7ed4c54..c5611a9 100644
--- a/src/subcommand/remove.rs
+++ b/src/subcommand/remove.rs
@@ -1,5 +1,6 @@
 use crate::env::Env;
 use crate::util;
+
 use anyhow::Result;
 use structopt::StructOpt;
 
diff --git a/src/util.rs b/src/util.rs
index e4a537f..c00f7e6 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -2,12 +2,25 @@ use crate::db::DB;
 use crate::dir::Dir;
 use crate::env::Env;
 use crate::types::Epoch;
+
 use anyhow::{anyhow, bail, Context, Result};
 use std::cmp::{Ordering, PartialOrd};
 use std::io::{Read, Write};
+use std::path::Path;
 use std::process::{Command, Stdio};
 use std::time::SystemTime;
 
+#[cfg(unix)]
+pub fn path_to_bytes<P: AsRef<Path>>(path: &P) -> Option<&[u8]> {
+    use std::os::unix::ffi::OsStrExt;
+    Some(path.as_ref().as_os_str().as_bytes())
+}
+
+#[cfg(not(unix))]
+pub fn path_to_bytes<P: AsRef<Path>>(path: &P) -> Option<&[u8]> {
+    Some(path.as_ref().to_str()?.as_bytes())
+}
+
 pub fn get_db(env: &Env) -> Result<DB> {
     let path = env
         .data
@@ -19,19 +32,19 @@ pub fn get_db(env: &Env) -> Result<DB> {
 pub fn get_current_time() -> Result<Epoch> {
     let current_time = SystemTime::now()
         .duration_since(SystemTime::UNIX_EPOCH)
-        .with_context(|| "system clock set to invalid time")?
+        .context("system clock set to invalid time")?
         .as_secs();
 
     Ok(current_time as Epoch)
 }
 
-pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
+pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<Vec<u8>>> {
     let mut fzf = Command::new("fzf")
         .arg("-n2..")
         .stdin(Stdio::piped())
         .stdout(Stdio::piped())
         .spawn()
-        .with_context(|| anyhow!("could not launch fzf"))?;
+        .context("could not launch fzf")?;
 
     let fzf_stdin = fzf
         .stdin
@@ -52,8 +65,15 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
     for dir in dirs.iter() {
         // ensure that frecency fits in 4 characters
         let frecency = clamp(dir.rank, 0.0, 9999.0);
-        writeln!(fzf_stdin, "{:>4.0}        {}", frecency, dir.path)
-            .with_context(|| anyhow!("could not write into fzf stdin"))?;
+
+        if let Some(path_bytes) = path_to_bytes(&dir.path) {
+            (|| {
+                write!(fzf_stdin, "{:>4.0}        ", frecency)?;
+                fzf_stdin.write_all(path_bytes)?;
+                fzf_stdin.write_all(b"\n")
+            })()
+            .context("could not write into fzf stdin")?;
+        }
     }
 
     let fzf_stdout = fzf
@@ -61,17 +81,16 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<String>> {
         .as_mut()
         .ok_or_else(|| anyhow!("could not connect to fzf stdout"))?;
 
-    let mut output = String::new();
+    let mut buffer = Vec::new();
     fzf_stdout
-        .read_to_string(&mut output)
-        .with_context(|| anyhow!("could not read from fzf stdout"))?;
-
-    let status = fzf.wait().with_context(|| "could not wait on fzf")?;
+        .read_to_end(&mut buffer)
+        .context("could not read from fzf stdout")?;
 
+    let status = fzf.wait().context("wait failed on fzf")?;
     match status.code() {
         // normal exit
-        Some(0) => match output.get(12..) {
-            Some(path) => Ok(Some(path.to_string())),
+        Some(0) => match buffer.get(12..buffer.len() - 1) {
+            Some(path) => Ok(Some(path.to_vec())),
             None => bail!("fzf returned invalid output"),
         },
 

From 76dfaad9a1dbace9bb9ef3f6c297a53143348385 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Fri, 27 Mar 2020 19:19:29 +0530
Subject: [PATCH 04/16] Set max DB size to 8 MiB

---
 src/db.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/db.rs b/src/db.rs
index a3806a0..eba07e8 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -20,7 +20,10 @@ impl DB {
         let dirs = match File::open(&path) {
             Ok(file) => {
                 let reader = BufReader::new(&file);
-                bincode::deserialize_from(reader).context("could not deserialize database")?
+                bincode::config()
+                    .limit(8 * 1024 * 1024) // only databases upto 8 MiB are supported
+                    .deserialize_from(reader)
+                    .context("could not deserialize database")?
             }
             Err(err) => match err.kind() {
                 io::ErrorKind::NotFound => Vec::<Dir>::new(),

From 5547fb4b802b2837d2750d28d5c942c63a36c5de Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Fri, 27 Mar 2020 19:25:37 +0530
Subject: [PATCH 05/16] Rename `migrate` command to `import`

---
 README.md                                | 4 ++--
 src/db.rs                                | 4 ++--
 src/main.rs                              | 4 ++--
 src/subcommand/{migrate.rs => import.rs} | 8 ++++----
 src/subcommand/mod.rs                    | 4 ++--
 5 files changed, 12 insertions(+), 12 deletions(-)
 rename src/subcommand/{migrate.rs => import.rs} (66%)

diff --git a/README.md b/README.md
index a57665d..6a3dbf5 100644
--- a/README.md
+++ b/README.md
@@ -60,10 +60,10 @@ If you want the interactive fuzzy selection feature, you will also need to insta
 
 ### Step 2: Adding `zoxide` to your shell
 
-If you currently use `z`, `z.lua`, or `zsh-z`, you may want to first migrate your existing database to `zoxide`:
+If you currently use `z`, `z.lua`, or `zsh-z`, you may want to first import your existing database into `zoxide`:
 
 ```sh
-zoxide migrate /path/to/db
+zoxide import /path/to/db
 ```
 
 #### zsh
diff --git a/src/db.rs b/src/db.rs
index eba07e8..e4973c8 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -54,10 +54,10 @@ impl DB {
         Ok(())
     }
 
-    pub fn migrate<P: AsRef<Path>>(&mut self, path: P, merge: bool) -> Result<()> {
+    pub fn import<P: AsRef<Path>>(&mut self, path: P, merge: bool) -> Result<()> {
         if !self.dirs.is_empty() && !merge {
             bail!(indoc!(
-                "To prevent conflicts, you can only migrate from z with an empty zoxide database!
+                "To prevent conflicts, you can only import from z with an empty zoxide database!
                 If you wish to merge the two, specify the `--merge` flag."
             ));
         }
diff --git a/src/main.rs b/src/main.rs
index de5d4c7..7e8e681 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -14,8 +14,8 @@ use structopt::StructOpt;
 #[structopt(about = "A cd command that learns your habits")]
 enum Zoxide {
     Add(subcommand::Add),
+    Import(subcommand::Import),
     Init(subcommand::Init),
-    Migrate(subcommand::Migrate),
     Query(subcommand::Query),
     Remove(subcommand::Remove),
 }
@@ -28,8 +28,8 @@ pub fn main() -> Result<()> {
 
     match opt {
         Zoxide::Add(add) => add.run(&env)?,
+        Zoxide::Import(import) => import.run(&env)?,
         Zoxide::Init(init) => init.run()?,
-        Zoxide::Migrate(migrate) => migrate.run(&env)?,
         Zoxide::Query(query) => query.run(&env)?,
         Zoxide::Remove(remove) => remove.run(&env)?,
     };
diff --git a/src/subcommand/migrate.rs b/src/subcommand/import.rs
similarity index 66%
rename from src/subcommand/migrate.rs
rename to src/subcommand/import.rs
index 55c5d45..db2926a 100644
--- a/src/subcommand/migrate.rs
+++ b/src/subcommand/import.rs
@@ -5,16 +5,16 @@ use anyhow::Result;
 use structopt::StructOpt;
 
 #[derive(Debug, StructOpt)]
-#[structopt(about = "Migrate from z database")]
-pub struct Migrate {
+#[structopt(about = "Import from z database")]
+pub struct Import {
     path: String,
 
     #[structopt(long, help = "Merge entries into existing database")]
     merge: bool,
 }
 
-impl Migrate {
+impl Import {
     pub fn run(&self, env: &Env) -> Result<()> {
-        util::get_db(env)?.migrate(&self.path, self.merge)
+        util::get_db(env)?.import(&self.path, self.merge)
     }
 }
diff --git a/src/subcommand/mod.rs b/src/subcommand/mod.rs
index 0aae3cf..6ca5818 100644
--- a/src/subcommand/mod.rs
+++ b/src/subcommand/mod.rs
@@ -1,11 +1,11 @@
 mod add;
+mod import;
 mod init;
-mod migrate;
 mod query;
 mod remove;
 
 pub use add::Add;
+pub use import::Import;
 pub use init::Init;
-pub use migrate::Migrate;
 pub use query::Query;
 pub use remove::Remove;

From d4fb1a05cfed6b8e0ed1d79f231d2e6f7dc735a0 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Sat, 28 Mar 2020 00:38:36 +0530
Subject: [PATCH 06/16] Manually parse environment variables

---
 Cargo.lock               | 10 ----------
 Cargo.toml               |  1 -
 src/config.rs            | 41 ++++++++++++++++++++++++++++++++++++++++
 src/db.rs                |  6 +++---
 src/env.rs               | 21 --------------------
 src/main.rs              | 17 ++++++-----------
 src/subcommand/add.rs    |  9 ++++-----
 src/subcommand/import.rs |  5 ++---
 src/subcommand/query.rs  | 15 +++++++--------
 src/subcommand/remove.rs |  5 ++---
 src/util.rs              | 10 ++++------
 11 files changed, 69 insertions(+), 71 deletions(-)
 create mode 100644 src/config.rs
 delete mode 100644 src/env.rs

diff --git a/Cargo.lock b/Cargo.lock
index 7e40c16..a83395e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -136,14 +136,6 @@ dependencies = [
  "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "envy"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "getrandom"
 version = "0.1.14"
@@ -421,7 +413,6 @@ dependencies = [
  "bstr 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "envy 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -446,7 +437,6 @@ dependencies = [
 "checksum crossbeam-utils 0.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "c3c7c73a2d1e9fc0886a08b93e98eb643461230d5f1925e4036204d5f2e261a8"
 "checksum dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "13aea89a5c93364a98e9b37b2fa237effbb694d5cfe01c5b70941f7eb087d5e3"
 "checksum dirs-sys 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "afa0b23de8fd801745c471deffa6e12d248f962c9fd4b4c33787b055599bde7b"
-"checksum envy 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f938a4abd5b75fe3737902dbc2e79ca142cc1526827a9e40b829a086758531a9"
 "checksum getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
 "checksum heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "20564e78d53d2bb135c343b3f47714a56af2061f1c928fdb541dc7b9fdd94205"
 "checksum hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "1010591b26bbfe835e9faeabeb11866061cc7dcebffd56ad7d0942d0e61aefd8"
diff --git a/Cargo.toml b/Cargo.toml
index e31e3a3..8e495ea 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,7 +17,6 @@ anyhow = "1.0.27"
 bincode = "1.2.1"
 clap = "2.33.0"
 dirs = "2.0.2"
-envy = "0.4.1"
 indoc = "0.3.5"
 serde = { version = "1.0.105", features = ["derive"] }
 structopt = "0.3.12"
diff --git a/src/config.rs b/src/config.rs
new file mode 100644
index 0000000..cdde196
--- /dev/null
+++ b/src/config.rs
@@ -0,0 +1,41 @@
+use crate::types::Rank;
+
+use anyhow::{bail, Context, Result};
+use std::env;
+use std::fs;
+use std::path::PathBuf;
+
+pub fn zo_data() -> Result<PathBuf> {
+    let path = match env::var_os("_ZO_DATA") {
+        Some(data_osstr) => PathBuf::from(data_osstr),
+        None => {
+            if let Some(mut cache_dir) = dirs::cache_dir() {
+                cache_dir.push("zoxide");
+                cache_dir
+            } else if let Some(mut home_dir) = dirs::home_dir() {
+                home_dir.push(".zoxide");
+                home_dir
+            } else {
+                bail!("could not generate default directory, please set _ZO_DATA manually");
+            }
+        }
+    };
+
+    fs::create_dir_all(&path).context("could not create _ZO_DATA directory")?;
+    Ok(path)
+}
+
+pub fn zo_maxage() -> Result<Rank> {
+    match env::var_os("_ZO_MAXAGE") {
+        Some(maxage_osstr) => match maxage_osstr.to_str() {
+            Some(maxage_str) => {
+                let maxage = maxage_str
+                    .parse::<i64>()
+                    .context("unable to parse _ZO_MAXAGE as integer")?;
+                Ok(maxage as Rank)
+            }
+            None => bail!("invalid Unicode in _ZO_MAXAGE"),
+        },
+        None => Ok(1000.0),
+    }
+}
diff --git a/src/db.rs b/src/db.rs
index e4973c8..ec01efb 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -163,11 +163,11 @@ impl DB {
             for dir in &mut self.dirs {
                 dir.rank *= factor;
             }
+
+            self.dirs.retain(|dir| dir.rank >= 1.0);
         }
 
-        self.dirs.retain(|dir| dir.rank >= 1.0);
         self.modified = true;
-
         Ok(())
     }
 
@@ -214,7 +214,7 @@ impl DB {
 
     fn get_path_tmp(&self) -> PathBuf {
         let mut path_tmp = self.path.clone();
-        path_tmp.set_file_name(".zo.tmp");
+        path_tmp.set_file_name("db.zo.tmp");
         path_tmp
     }
 
diff --git a/src/env.rs b/src/env.rs
deleted file mode 100644
index ec974f8..0000000
--- a/src/env.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-use serde::Deserialize;
-use std::path::PathBuf;
-
-#[derive(Deserialize, Debug)]
-pub struct Env {
-    #[serde(default = "default_maxage")]
-    pub maxage: i64,
-
-    #[serde(default = "default_data")]
-    pub data: Option<PathBuf>,
-}
-
-fn default_maxage() -> i64 {
-    1000
-}
-
-fn default_data() -> Option<PathBuf> {
-    let mut path = dirs::home_dir()?;
-    path.push(".zo");
-    Some(path)
-}
diff --git a/src/main.rs b/src/main.rs
index 7e8e681..f1c2766 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,13 +1,11 @@
+mod config;
 mod db;
 mod dir;
-mod env;
 mod subcommand;
 mod types;
 mod util;
 
-use crate::env::Env;
-
-use anyhow::{Context, Result};
+use anyhow::Result;
 use structopt::StructOpt;
 
 #[derive(Debug, StructOpt)]
@@ -22,16 +20,13 @@ enum Zoxide {
 
 pub fn main() -> Result<()> {
     let opt = Zoxide::from_args();
-    let env = envy::prefixed("_ZO_")
-        .from_env::<Env>()
-        .context("could not parse environment variables")?;
 
     match opt {
-        Zoxide::Add(add) => add.run(&env)?,
-        Zoxide::Import(import) => import.run(&env)?,
+        Zoxide::Add(add) => add.run()?,
+        Zoxide::Import(import) => import.run()?,
         Zoxide::Init(init) => init.run()?,
-        Zoxide::Query(query) => query.run(&env)?,
-        Zoxide::Remove(remove) => remove.run(&env)?,
+        Zoxide::Query(query) => query.run()?,
+        Zoxide::Remove(remove) => remove.run()?,
     };
 
     Ok(())
diff --git a/src/subcommand/add.rs b/src/subcommand/add.rs
index 35160fb..71550ee 100644
--- a/src/subcommand/add.rs
+++ b/src/subcommand/add.rs
@@ -1,5 +1,4 @@
-use crate::env::Env;
-use crate::types::Rank;
+use crate::config;
 use crate::util;
 
 use anyhow::{Context, Result};
@@ -13,10 +12,10 @@ pub struct Add {
 }
 
 impl Add {
-    pub fn run(&self, env: &Env) -> Result<()> {
-        let mut db = util::get_db(env)?;
+    pub fn run(&self) -> Result<()> {
+        let mut db = util::get_db()?;
         let now = util::get_current_time()?;
-        let maxage = env.maxage as Rank;
+        let maxage = config::zo_maxage()?;
 
         match &self.path {
             Some(path) => db.add(path, maxage, now),
diff --git a/src/subcommand/import.rs b/src/subcommand/import.rs
index db2926a..f691afd 100644
--- a/src/subcommand/import.rs
+++ b/src/subcommand/import.rs
@@ -1,4 +1,3 @@
-use crate::env::Env;
 use crate::util;
 
 use anyhow::Result;
@@ -14,7 +13,7 @@ pub struct Import {
 }
 
 impl Import {
-    pub fn run(&self, env: &Env) -> Result<()> {
-        util::get_db(env)?.import(&self.path, self.merge)
+    pub fn run(&self) -> Result<()> {
+        util::get_db()?.import(&self.path, self.merge)
     }
 }
diff --git a/src/subcommand/query.rs b/src/subcommand/query.rs
index eea7c51..4bae377 100644
--- a/src/subcommand/query.rs
+++ b/src/subcommand/query.rs
@@ -1,4 +1,3 @@
-use crate::env::Env;
 use crate::util;
 
 use anyhow::{bail, Result};
@@ -15,11 +14,11 @@ pub struct Query {
 }
 
 impl Query {
-    pub fn run(mut self, env: &Env) -> Result<()> {
+    pub fn run(mut self) -> Result<()> {
         let path_opt = if self.interactive {
-            self.query_interactive(env)?
+            self.query_interactive()?
         } else {
-            self.query(env)?
+            self.query()?
         };
 
         match path_opt {
@@ -36,7 +35,7 @@ impl Query {
         Ok(())
     }
 
-    fn query(&mut self, env: &Env) -> Result<Option<Vec<u8>>> {
+    fn query(&mut self) -> Result<Option<Vec<u8>>> {
         if let [path] = self.keywords.as_slice() {
             if Path::new(path).is_dir() {
                 return Ok(Some(path.as_bytes().to_vec()));
@@ -49,7 +48,7 @@ impl Query {
             *keyword = keyword.to_lowercase();
         }
 
-        if let Some(dir) = util::get_db(env)?.query(&self.keywords, now) {
+        if let Some(dir) = util::get_db()?.query(&self.keywords, now) {
             // `path_to_bytes` is guaranteed to succeed here since
             // the path has already been queried successfully
             let path_bytes = util::path_to_bytes(&dir.path).unwrap();
@@ -59,14 +58,14 @@ impl Query {
         }
     }
 
-    fn query_interactive(&mut self, env: &Env) -> Result<Option<Vec<u8>>> {
+    fn query_interactive(&mut self) -> Result<Option<Vec<u8>>> {
         let now = util::get_current_time()?;
 
         for keyword in &mut self.keywords {
             *keyword = keyword.to_lowercase();
         }
 
-        let dirs = util::get_db(env)?.query_all(&self.keywords);
+        let dirs = util::get_db()?.query_all(&self.keywords);
         util::fzf_helper(now, dirs)
     }
 }
diff --git a/src/subcommand/remove.rs b/src/subcommand/remove.rs
index c5611a9..b115c28 100644
--- a/src/subcommand/remove.rs
+++ b/src/subcommand/remove.rs
@@ -1,4 +1,3 @@
-use crate::env::Env;
 use crate::util;
 
 use anyhow::Result;
@@ -11,7 +10,7 @@ pub struct Remove {
 }
 
 impl Remove {
-    pub fn run(&self, env: &Env) -> Result<()> {
-        util::get_db(env)?.remove(&self.path)
+    pub fn run(&self) -> Result<()> {
+        util::get_db()?.remove(&self.path)
     }
 }
diff --git a/src/util.rs b/src/util.rs
index c00f7e6..b6615ce 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -1,6 +1,6 @@
+use crate::config;
 use crate::db::DB;
 use crate::dir::Dir;
-use crate::env::Env;
 use crate::types::Epoch;
 
 use anyhow::{anyhow, bail, Context, Result};
@@ -21,11 +21,9 @@ pub fn path_to_bytes<P: AsRef<Path>>(path: &P) -> Option<&[u8]> {
     Some(path.as_ref().to_str()?.as_bytes())
 }
 
-pub fn get_db(env: &Env) -> Result<DB> {
-    let path = env
-        .data
-        .as_ref()
-        .ok_or_else(|| anyhow!("could not locate database file"))?;
+pub fn get_db() -> Result<DB> {
+    let mut path = config::zo_data()?;
+    path.push("db.zo");
     DB::open(path)
 }
 

From f29b642ffc6f97bf5d4ce466fc09b05bbed66a54 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Sat, 28 Mar 2020 00:43:33 +0530
Subject: [PATCH 07/16] Remove FIXME

---
 src/db.rs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/db.rs b/src/db.rs
index ec01efb..dbb9d3e 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -117,8 +117,6 @@ impl DB {
                         };
                     }
 
-                    // FIXME: When we switch to PathBuf for storing directories inside Dir, just
-                    // pass `PathBuf::from(path_str)`
                     self.dirs.push(Dir {
                         path: path_abs,
                         rank,

From 11901068490bae0384255af1e56d120515a4d1ba Mon Sep 17 00:00:00 2001
From: Cole Helbling <cole.e.helbling@outlook.com>
Date: Fri, 27 Mar 2020 14:56:48 -0700
Subject: [PATCH 08/16] Implement _ZO_EXCLUDE_DIRS

_ZO_EXCLUDE_DIRS is a list of paths (separated by colons, `:`, on
Unix-based systems, and semicolons, `;`, on Windows) that should be
excluded from the database. Example:

    _ZO_EXCLUDE_DIRS="$HOME:$HOME/something/super/secret:$HOME/caused/by/background/cds"
---
 src/config.rs         |  8 ++++++++
 src/subcommand/add.rs | 23 ++++++++++++++---------
 2 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/src/config.rs b/src/config.rs
index cdde196..39a8ceb 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,6 +1,7 @@
 use crate::types::Rank;
 
 use anyhow::{bail, Context, Result};
+
 use std::env;
 use std::fs;
 use std::path::PathBuf;
@@ -25,6 +26,13 @@ pub fn zo_data() -> Result<PathBuf> {
     Ok(path)
 }
 
+pub fn zo_exclude_dirs() -> Vec<PathBuf> {
+    match env::var_os("_ZO_EXCLUDE_DIRS") {
+        Some(dirs_osstr) => env::split_paths(&dirs_osstr).collect(),
+        None => Vec::new(),
+    }
+}
+
 pub fn zo_maxage() -> Result<Rank> {
     match env::var_os("_ZO_MAXAGE") {
         Some(maxage_osstr) => match maxage_osstr.to_str() {
diff --git a/src/subcommand/add.rs b/src/subcommand/add.rs
index 71550ee..c3c4b22 100644
--- a/src/subcommand/add.rs
+++ b/src/subcommand/add.rs
@@ -2,13 +2,15 @@ use crate::config;
 use crate::util;
 
 use anyhow::{Context, Result};
-use std::env;
 use structopt::StructOpt;
 
+use std::env;
+use std::path::PathBuf;
+
 #[derive(Debug, StructOpt)]
 #[structopt(about = "Add a new directory or increment its rank")]
 pub struct Add {
-    path: Option<String>,
+    path: Option<PathBuf>,
 }
 
 impl Add {
@@ -16,14 +18,17 @@ impl Add {
         let mut db = util::get_db()?;
         let now = util::get_current_time()?;
         let maxage = config::zo_maxage()?;
+        let excluded_dirs = config::zo_exclude_dirs();
 
-        match &self.path {
-            Some(path) => db.add(path, maxage, now),
-            None => {
-                let current_dir =
-                    env::current_dir().context("unable to fetch current directory")?;
-                db.add(current_dir, maxage, now)
-            }
+        let path = match &self.path {
+            Some(path) => path.clone(),
+            None => env::current_dir().context("unable to fetch current directory")?,
+        };
+
+        if excluded_dirs.contains(&path) {
+            return Ok(());
         }
+
+        db.add(path, maxage, now)
     }
 }

From 91cced7333879ebe1e14138b91960f20037ada19 Mon Sep 17 00:00:00 2001
From: Cole Helbling <cole.e.helbling@outlook.com>
Date: Fri, 27 Mar 2020 23:06:25 -0700
Subject: [PATCH 09/16] Document _ZO_EXCLUDE_DIRS env var

---
 README.md | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 6a3dbf5..9cbe0e6 100644
--- a/README.md
+++ b/README.md
@@ -116,6 +116,9 @@ NOTE: There is no PWD hook provided for POSIX shells.
 
 ### Environment variables
 
-- `$_ZO_ECHO`: `z` will print the matched directory before navigating to it
 - `$_ZO_DATA`: sets the location of the database (default: `~/.zo`)
+- `$_ZO_ECHO`: `z` will print the matched directory before navigating to it
+- `$_ZO_EXCLUDE_DIRS`: list of directories separated by platform-specific
+    characters (`:` on Linux and macOS, and `;` on Windows) to be excluded from
+    the database
 - `$_ZO_MAXAGE`: sets the maximum total rank after which entries start getting deleted

From 057ed96c0a7770fe9dd06b15d120fa1a3bdb6f91 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Sat, 28 Mar 2020 23:51:46 +0530
Subject: [PATCH 10/16] Refactor DB architecture

---
 src/config.rs            |   7 ++-
 src/db.rs                | 130 ++++++++++++++++++++++++++++-----------
 src/dir.rs               |   5 +-
 src/main.rs              |   1 -
 src/subcommand/import.rs |   4 +-
 src/subcommand/query.rs  |   3 +-
 src/subcommand/remove.rs |   4 +-
 src/types.rs             |   2 -
 src/util.rs              |   4 +-
 9 files changed, 113 insertions(+), 47 deletions(-)
 delete mode 100644 src/types.rs

diff --git a/src/config.rs b/src/config.rs
index 39a8ceb..6e41b1b 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,4 +1,5 @@
-use crate::types::Rank;
+use crate::db::DBVersion;
+use crate::dir::Rank;
 
 use anyhow::{bail, Context, Result};
 
@@ -6,6 +7,10 @@ use std::env;
 use std::fs;
 use std::path::PathBuf;
 
+pub const DB_MAX_SIZE: u64 = 8 * 1024 * 1024; // 8 MiB
+
+pub const DB_VERSION: DBVersion = 3;
+
 pub fn zo_data() -> Result<PathBuf> {
     let path = match env::var_os("_ZO_DATA") {
         Some(data_osstr) => PathBuf::from(data_osstr),
diff --git a/src/db.rs b/src/db.rs
index dbb9d3e..32d3f2a 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -1,40 +1,75 @@
-use crate::dir::Dir;
-use crate::types::{Epoch, Rank};
+use crate::config;
+use crate::dir::{Dir, Epoch, Rank};
 
 use anyhow::{anyhow, bail, Context, Result};
 use indoc::indoc;
+use serde::{Deserialize, Serialize};
+
+use std::cmp::Ordering;
 use std::fs::{self, File};
 use std::io::{self, BufRead, BufReader, BufWriter};
 use std::path::{Path, PathBuf};
 
+pub use i32 as DBVersion;
+
 pub struct DB {
-    path: PathBuf,
-    dirs: Vec<Dir>,
+    data: DBData,
     modified: bool,
+    path: PathBuf,
+    path_old: Option<PathBuf>,
 }
 
 impl DB {
     pub fn open<P: AsRef<Path>>(path: P) -> Result<DB> {
-        let path = path.as_ref().to_path_buf();
-
-        let dirs = match File::open(&path) {
+        let data = match File::open(&path) {
             Ok(file) => {
                 let reader = BufReader::new(&file);
                 bincode::config()
-                    .limit(8 * 1024 * 1024) // only databases upto 8 MiB are supported
+                    .limit(config::DB_MAX_SIZE)
                     .deserialize_from(reader)
                     .context("could not deserialize database")?
             }
             Err(err) => match err.kind() {
-                io::ErrorKind::NotFound => Vec::<Dir>::new(),
+                io::ErrorKind::NotFound => DBData::default(),
                 _ => return Err(err).context("could not open database file"),
             },
         };
 
+        if data.version != config::DB_VERSION {
+            bail!("this database version ({}) is unsupported", data.version);
+        }
+
         Ok(DB {
-            path,
-            dirs,
+            data,
             modified: false,
+            path: path.as_ref().to_path_buf(),
+            path_old: None,
+        })
+    }
+
+    pub fn open_old<P1, P2>(path_old: P1, path: P2) -> Result<DB>
+    where
+        P1: AsRef<Path>,
+        P2: AsRef<Path>,
+    {
+        let file = File::open(&path_old).context("could not open old database file")?;
+        let reader = BufReader::new(&file);
+
+        let dirs = bincode::config()
+            .limit(config::DB_MAX_SIZE)
+            .deserialize_from(reader)
+            .context("could not deserialize old database")?;
+
+        let data = DBData {
+            version: config::DB_VERSION,
+            dirs,
+        };
+
+        Ok(DB {
+            data,
+            modified: true,
+            path: path.as_ref().to_path_buf(),
+            path_old: Some(path_old.as_ref().to_path_buf()),
         })
     }
 
@@ -46,7 +81,8 @@ impl DB {
                 File::create(&path_tmp).context("could not open temporary database file")?;
 
             let writer = BufWriter::new(&file_tmp);
-            bincode::serialize_into(writer, &self.dirs).context("could not serialize database")?;
+            bincode::serialize_into(writer, &self.data)
+                .context("could not serialize database")?;
 
             fs::rename(&path_tmp, &self.path).context("could not move temporary database file")?;
         }
@@ -55,7 +91,7 @@ impl DB {
     }
 
     pub fn import<P: AsRef<Path>>(&mut self, path: P, merge: bool) -> Result<()> {
-        if !self.dirs.is_empty() && !merge {
+        if !self.data.dirs.is_empty() && !merge {
             bail!(indoc!(
                 "To prevent conflicts, you can only import from z with an empty zoxide database!
                 If you wish to merge the two, specify the `--merge` flag."
@@ -109,7 +145,9 @@ impl DB {
                     if merge {
                         // If the path exists in the database, add the ranks and set the epoch to
                         // the largest of the parsed epoch and the already present epoch.
-                        if let Some(dir) = self.dirs.iter_mut().find(|dir| dir.path == path_abs) {
+                        if let Some(dir) =
+                            self.data.dirs.iter_mut().find(|dir| dir.path == path_abs)
+                        {
                             dir.rank += rank;
                             dir.last_accessed = Epoch::max(epoch, dir.last_accessed);
 
@@ -117,7 +155,7 @@ impl DB {
                         };
                     }
 
-                    self.dirs.push(Dir {
+                    self.data.dirs.push(Dir {
                         path: path_abs,
                         rank,
                         last_accessed: epoch,
@@ -142,8 +180,8 @@ impl DB {
             .canonicalize()
             .with_context(|| anyhow!("could not access directory: {}", path.as_ref().display()))?;
 
-        match self.dirs.iter_mut().find(|dir| dir.path == path_abs) {
-            None => self.dirs.push(Dir {
+        match self.data.dirs.iter_mut().find(|dir| dir.path == path_abs) {
+            None => self.data.dirs.push(Dir {
                 path: path_abs,
                 last_accessed: now,
                 rank: 1.0,
@@ -154,15 +192,15 @@ impl DB {
             }
         };
 
-        let sum_age = self.dirs.iter().map(|dir| dir.rank).sum::<Rank>();
+        let sum_age = self.data.dirs.iter().map(|dir| dir.rank).sum::<Rank>();
 
         if sum_age > max_age {
             let factor = 0.9 * max_age / sum_age;
-            for dir in &mut self.dirs {
+            for dir in &mut self.data.dirs {
                 dir.rank *= factor;
             }
 
-            self.dirs.retain(|dir| dir.rank >= 1.0);
+            self.data.dirs.retain(|dir| dir.rank >= 1.0);
         }
 
         self.modified = true;
@@ -170,26 +208,36 @@ impl DB {
     }
 
     pub fn query(&mut self, keywords: &[String], now: Epoch) -> Option<Dir> {
-        let (idx, dir) = self
+        let (idx, dir, _) = self
+            .data
             .dirs
             .iter()
             .enumerate()
             .filter(|(_, dir)| dir.is_match(&keywords))
-            .max_by_key(|(_, dir)| dir.get_frecency(now) as i64)?;
+            .map(|(idx, dir)| (idx, dir, dir.get_frecency(now)))
+            .max_by(|(_, _, frecency1), (_, _, frecency2)| {
+                frecency1.partial_cmp(frecency2).unwrap_or(Ordering::Equal)
+            })?;
 
         if dir.is_dir() {
             Some(dir.to_owned())
         } else {
-            self.dirs.swap_remove(idx);
+            self.data.dirs.swap_remove(idx);
             self.modified = true;
             self.query(keywords, now)
         }
     }
 
     pub fn query_all(&mut self, keywords: &[String]) -> Vec<Dir> {
-        self.remove_invalid();
+        let orig_len = self.data.dirs.len();
+        self.data.dirs.retain(Dir::is_dir);
 
-        self.dirs
+        if orig_len != self.data.dirs.len() {
+            self.modified = true;
+        }
+
+        self.data
+            .dirs
             .iter()
             .filter(|dir| dir.is_match(&keywords))
             .cloned()
@@ -202,8 +250,8 @@ impl DB {
             Err(_) => path.as_ref().to_path_buf(),
         };
 
-        if let Some(idx) = self.dirs.iter().position(|dir| dir.path == path_abs) {
-            self.dirs.swap_remove(idx);
+        if let Some(idx) = self.data.dirs.iter().position(|dir| dir.path == path_abs) {
+            self.data.dirs.swap_remove(idx);
             self.modified = true;
         }
 
@@ -215,21 +263,31 @@ impl DB {
         path_tmp.set_file_name("db.zo.tmp");
         path_tmp
     }
-
-    fn remove_invalid(&mut self) {
-        let orig_len = self.dirs.len();
-        self.dirs.retain(Dir::is_dir);
-
-        if orig_len != self.dirs.len() {
-            self.modified = true;
-        }
-    }
 }
 
 impl Drop for DB {
     fn drop(&mut self) {
         if let Err(e) = self.save() {
             eprintln!("{:#}", e);
+        } else if let Some(path_old) = &self.path_old {
+            if let Err(e) = fs::remove_file(path_old).context("could not remove old database") {
+                eprintln!("{:#}", e);
+            }
+        }
+    }
+}
+
+#[derive(Debug, Deserialize, Serialize)]
+struct DBData {
+    version: DBVersion,
+    dirs: Vec<Dir>,
+}
+
+impl Default for DBData {
+    fn default() -> DBData {
+        DBData {
+            version: config::DB_VERSION,
+            dirs: Vec::new(),
         }
     }
 }
diff --git a/src/dir.rs b/src/dir.rs
index c24d74a..aa7f67d 100644
--- a/src/dir.rs
+++ b/src/dir.rs
@@ -1,8 +1,9 @@
-use crate::types::{Epoch, Rank};
-
 use serde::{Deserialize, Serialize};
 use std::path::PathBuf;
 
+pub use f64 as Rank;
+pub use i64 as Epoch; // use a signed integer so subtraction can be performed on it
+
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 pub struct Dir {
     pub path: PathBuf,
diff --git a/src/main.rs b/src/main.rs
index f1c2766..a480b45 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,7 +2,6 @@ mod config;
 mod db;
 mod dir;
 mod subcommand;
-mod types;
 mod util;
 
 use anyhow::Result;
diff --git a/src/subcommand/import.rs b/src/subcommand/import.rs
index f691afd..3e10191 100644
--- a/src/subcommand/import.rs
+++ b/src/subcommand/import.rs
@@ -3,10 +3,12 @@ use crate::util;
 use anyhow::Result;
 use structopt::StructOpt;
 
+use std::path::PathBuf;
+
 #[derive(Debug, StructOpt)]
 #[structopt(about = "Import from z database")]
 pub struct Import {
-    path: String,
+    path: PathBuf,
 
     #[structopt(long, help = "Merge entries into existing database")]
     merge: bool,
diff --git a/src/subcommand/query.rs b/src/subcommand/query.rs
index 4bae377..cba97d1 100644
--- a/src/subcommand/query.rs
+++ b/src/subcommand/query.rs
@@ -1,9 +1,10 @@
 use crate::util;
 
 use anyhow::{bail, Result};
+use structopt::StructOpt;
+
 use std::io::{self, Write};
 use std::path::Path;
-use structopt::StructOpt;
 
 #[derive(Debug, StructOpt)]
 #[structopt(about = "Search for a directory")]
diff --git a/src/subcommand/remove.rs b/src/subcommand/remove.rs
index b115c28..5ba579d 100644
--- a/src/subcommand/remove.rs
+++ b/src/subcommand/remove.rs
@@ -3,10 +3,12 @@ use crate::util;
 use anyhow::Result;
 use structopt::StructOpt;
 
+use std::path::PathBuf;
+
 #[derive(Debug, StructOpt)]
 #[structopt(about = "Remove a directory")]
 pub struct Remove {
-    path: String,
+    path: PathBuf,
 }
 
 impl Remove {
diff --git a/src/types.rs b/src/types.rs
deleted file mode 100644
index 1ddffd1..0000000
--- a/src/types.rs
+++ /dev/null
@@ -1,2 +0,0 @@
-pub use f64 as Rank;
-pub use i64 as Epoch; // use a signed integer so subtraction can be performed on it
diff --git a/src/util.rs b/src/util.rs
index b6615ce..c9e4057 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -1,9 +1,9 @@
 use crate::config;
 use crate::db::DB;
-use crate::dir::Dir;
-use crate::types::Epoch;
+use crate::dir::{Dir, Epoch};
 
 use anyhow::{anyhow, bail, Context, Result};
+
 use std::cmp::{Ordering, PartialOrd};
 use std::io::{Read, Write};
 use std::path::Path;

From d4c8297f9bf416a894a1eea3721b1db12d0c785b Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Sun, 29 Mar 2020 11:55:21 +0530
Subject: [PATCH 11/16] Use UUID4 for temporary database file name

---
 Cargo.lock | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 Cargo.toml |  1 +
 src/db.rs  | 15 ++++++++++----
 3 files changed, 69 insertions(+), 4 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index a83395e..0baa4e8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -198,6 +198,11 @@ name = "memchr"
 version = "2.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "ppv-lite86"
+version = "0.2.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "proc-macro-error"
 version = "0.4.12"
@@ -243,6 +248,43 @@ dependencies = [
  "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rand"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_hc"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.1.56"
@@ -370,6 +412,14 @@ name = "unindent"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "uuid"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "vec_map"
 version = "0.8.1"
@@ -416,6 +466,7 @@ dependencies = [
  "indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
+ "uuid 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [metadata]
@@ -445,11 +496,16 @@ dependencies = [
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 "checksum libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)" = "dea0c0405123bba743ee3f91f49b1c7cfb684eef0da0a50110f758ccf24cdff0"
 "checksum memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
+"checksum ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "74490b50b9fbe561ac330df47c08f3f33073d2d00c150f719147d7c54522fa1b"
 "checksum proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "18f33027081eba0a6d8aba6d1b1c3a3be58cbb12106341c2d5759fcd9b5277e7"
 "checksum proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "8a5b4b77fdb63c1eca72173d68d24501c54ab1269409f6b672c85deb18af69de"
 "checksum proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)" = "fcfdefadc3d57ca21cf17990a28ef4c0f7c61383a28cb7604cf4a18e6ede1420"
 "checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 "checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
+"checksum rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
+"checksum rand_chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
+"checksum rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
+"checksum rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
 "checksum redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)" = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
 "checksum redox_users 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "09b23093265f8d200fa7b4c2c76297f47e681c655f6f1285a8780d6a022f7431"
 "checksum regex-automata 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)" = "ae1ded71d66a4a97f5e961fd0cb25a5f366a42a41570d16a763a69c092c26ae4"
@@ -466,6 +522,7 @@ dependencies = [
 "checksum unicode-width 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
 "checksum unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
 "checksum unindent 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "63f18aa3b0e35fed5a0048f029558b1518095ffe2a0a31fb87c93dece93a4993"
+"checksum uuid 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9fde2f6a4bea1d6e007c4ad38c6839fa71cbb63b6dbf5b595aa38dc9b1093c11"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
 "checksum wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)" = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
diff --git a/Cargo.toml b/Cargo.toml
index 8e495ea..be13607 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,7 @@ dirs = "2.0.2"
 indoc = "0.3.5"
 serde = { version = "1.0.105", features = ["derive"] }
 structopt = "0.3.12"
+uuid = { version = "0.8.1", features = ["v4"] }
 
 [target.'cfg(unix)'.dependencies]
 bstr = "0.2.12"
diff --git a/src/db.rs b/src/db.rs
index 32d3f2a..9712366 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -4,6 +4,7 @@ use crate::dir::{Dir, Epoch, Rank};
 use anyhow::{anyhow, bail, Context, Result};
 use indoc::indoc;
 use serde::{Deserialize, Serialize};
+use uuid::Uuid;
 
 use std::cmp::Ordering;
 use std::fs::{self, File};
@@ -81,10 +82,13 @@ impl DB {
                 File::create(&path_tmp).context("could not open temporary database file")?;
 
             let writer = BufWriter::new(&file_tmp);
-            bincode::serialize_into(writer, &self.data)
-                .context("could not serialize database")?;
+            bincode::serialize_into(writer, &self.data).context("could not serialize database")?;
 
-            fs::rename(&path_tmp, &self.path).context("could not move temporary database file")?;
+            if let Err(e) = fs::rename(&path_tmp, &self.path) {
+                fs::remove_file(&path_tmp)
+                    .context("could not move or delete temporary database file")?;
+                return Err(e).context("could not move temporary database file");
+            }
         }
 
         Ok(())
@@ -259,8 +263,11 @@ impl DB {
     }
 
     fn get_path_tmp(&self) -> PathBuf {
+        let file_name = format!(".{}.zo", Uuid::new_v4());
+
         let mut path_tmp = self.path.clone();
-        path_tmp.set_file_name("db.zo.tmp");
+        path_tmp.set_file_name(file_name);
+
         path_tmp
     }
 }

From 9af0251bd6606729f5e862d19e0c0d7404f7fd2c Mon Sep 17 00:00:00 2001
From: Cole Helbling <cole.e.helbling@outlook.com>
Date: Sun, 29 Mar 2020 13:42:51 -0700
Subject: [PATCH 12/16] Rework database fallback for v0.3 (#47)

Support migration from old database
---
 README.md     |  5 ++++-
 src/config.rs | 24 ++++++++++++------------
 src/db.rs     |  2 +-
 src/util.rs   | 18 +++++++++++++++---
 4 files changed, 32 insertions(+), 17 deletions(-)

diff --git a/README.md b/README.md
index 9cbe0e6..6b59dda 100644
--- a/README.md
+++ b/README.md
@@ -116,9 +116,12 @@ NOTE: There is no PWD hook provided for POSIX shells.
 
 ### Environment variables
 
-- `$_ZO_DATA`: sets the location of the database (default: `~/.zo`)
+- `$_ZO_DATA_DIR`: directory where `zoxide` will store its data files (default:
+    platform-specific; see the [`dirs` documentation] for more information)
 - `$_ZO_ECHO`: `z` will print the matched directory before navigating to it
 - `$_ZO_EXCLUDE_DIRS`: list of directories separated by platform-specific
     characters (`:` on Linux and macOS, and `;` on Windows) to be excluded from
     the database
 - `$_ZO_MAXAGE`: sets the maximum total rank after which entries start getting deleted
+
+[`dirs` documentation]: https://docs.rs/dirs/latest/dirs/fn.data_local_dir.html
diff --git a/src/config.rs b/src/config.rs
index 6e41b1b..2376fff 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -8,27 +8,26 @@ use std::fs;
 use std::path::PathBuf;
 
 pub const DB_MAX_SIZE: u64 = 8 * 1024 * 1024; // 8 MiB
-
 pub const DB_VERSION: DBVersion = 3;
 
-pub fn zo_data() -> Result<PathBuf> {
-    let path = match env::var_os("_ZO_DATA") {
+pub fn zo_data_dir() -> Result<PathBuf> {
+    let data_dir = match env::var_os("_ZO_DATA_DIR") {
         Some(data_osstr) => PathBuf::from(data_osstr),
         None => {
-            if let Some(mut cache_dir) = dirs::cache_dir() {
-                cache_dir.push("zoxide");
-                cache_dir
-            } else if let Some(mut home_dir) = dirs::home_dir() {
-                home_dir.push(".zoxide");
-                home_dir
+            if let Some(mut data_dir) = dirs::data_local_dir() {
+                data_dir.push("zoxide");
+                data_dir
             } else {
-                bail!("could not generate default directory, please set _ZO_DATA manually");
+                bail!("could not find database directory, please set _ZO_DATA_DIR manually");
             }
         }
     };
 
-    fs::create_dir_all(&path).context("could not create _ZO_DATA directory")?;
-    Ok(path)
+    // This will fail when `data_dir` points to a file or a broken symlink, but
+    // will no-op on a valid symlink (to a directory), or an actual directory.
+    fs::create_dir_all(&data_dir).context("could not create data directory")?;
+
+    Ok(data_dir)
 }
 
 pub fn zo_exclude_dirs() -> Vec<PathBuf> {
@@ -45,6 +44,7 @@ pub fn zo_maxage() -> Result<Rank> {
                 let maxage = maxage_str
                     .parse::<i64>()
                     .context("unable to parse _ZO_MAXAGE as integer")?;
+
                 Ok(maxage as Rank)
             }
             None => bail!("invalid Unicode in _ZO_MAXAGE"),
diff --git a/src/db.rs b/src/db.rs
index 9712366..758865c 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -48,7 +48,7 @@ impl DB {
         })
     }
 
-    pub fn open_old<P1, P2>(path_old: P1, path: P2) -> Result<DB>
+    pub fn open_and_migrate<P1, P2>(path_old: P1, path: P2) -> Result<DB>
     where
         P1: AsRef<Path>,
         P2: AsRef<Path>,
diff --git a/src/util.rs b/src/util.rs
index c9e4057..80dcccd 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -22,9 +22,21 @@ pub fn path_to_bytes<P: AsRef<Path>>(path: &P) -> Option<&[u8]> {
 }
 
 pub fn get_db() -> Result<DB> {
-    let mut path = config::zo_data()?;
-    path.push("db.zo");
-    DB::open(path)
+    let mut db_path = config::zo_data_dir()?;
+    db_path.push("db.zo");
+
+    // FIXME: fallback to old database location; remove in next breaking version
+    if !db_path.is_file() {
+        if let Some(mut old_db_path) = dirs::home_dir() {
+            old_db_path.push(".zo");
+
+            if old_db_path.is_file() {
+                return DB::open_and_migrate(old_db_path, db_path);
+            }
+        }
+    }
+
+    DB::open(db_path)
 }
 
 pub fn get_current_time() -> Result<Epoch> {

From 78a3d0a3d9a2722f958a5f326270a6570dffc0f1 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Mon, 30 Mar 2020 02:22:54 +0530
Subject: [PATCH 13/16] Remove indoc dependency

---
 Cargo.lock | 36 ------------------------------------
 Cargo.toml |  1 -
 src/db.rs  |  9 ++++-----
 3 files changed, 4 insertions(+), 42 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 0baa4e8..3234a79 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -162,27 +162,6 @@ dependencies = [
  "libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "indoc"
-version = "0.3.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "indoc-impl 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "indoc-impl"
-version = "0.3.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "syn 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)",
- "unindent 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -227,11 +206,6 @@ dependencies = [
  "version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "proc-macro-hack"
-version = "0.5.14"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "proc-macro2"
 version = "1.0.9"
@@ -407,11 +381,6 @@ name = "unicode-xid"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
-[[package]]
-name = "unindent"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "uuid"
 version = "0.8.1"
@@ -463,7 +432,6 @@ dependencies = [
  "bstr 0.2.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.105 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.3.12 (registry+https://github.com/rust-lang/crates.io-index)",
  "uuid 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -491,15 +459,12 @@ dependencies = [
 "checksum getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
 "checksum heck 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "20564e78d53d2bb135c343b3f47714a56af2061f1c928fdb541dc7b9fdd94205"
 "checksum hermit-abi 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "1010591b26bbfe835e9faeabeb11866061cc7dcebffd56ad7d0942d0e61aefd8"
-"checksum indoc 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "79255cf29f5711995ddf9ec261b4057b1deb34e66c90656c201e41376872c544"
-"checksum indoc-impl 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "54554010aa3d17754e484005ea0022f1c93839aabc627c2c55f3d7b47206134c"
 "checksum lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 "checksum libc 0.2.68 (registry+https://github.com/rust-lang/crates.io-index)" = "dea0c0405123bba743ee3f91f49b1c7cfb684eef0da0a50110f758ccf24cdff0"
 "checksum memchr 2.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
 "checksum ppv-lite86 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "74490b50b9fbe561ac330df47c08f3f33073d2d00c150f719147d7c54522fa1b"
 "checksum proc-macro-error 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "18f33027081eba0a6d8aba6d1b1c3a3be58cbb12106341c2d5759fcd9b5277e7"
 "checksum proc-macro-error-attr 0.4.12 (registry+https://github.com/rust-lang/crates.io-index)" = "8a5b4b77fdb63c1eca72173d68d24501c54ab1269409f6b672c85deb18af69de"
-"checksum proc-macro-hack 0.5.14 (registry+https://github.com/rust-lang/crates.io-index)" = "fcfdefadc3d57ca21cf17990a28ef4c0f7c61383a28cb7604cf4a18e6ede1420"
 "checksum proc-macro2 1.0.9 (registry+https://github.com/rust-lang/crates.io-index)" = "6c09721c6781493a2a492a96b5a5bf19b65917fe6728884e7c44dd0c60ca3435"
 "checksum quote 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2bdc6c187c65bca4260c9011c9e3132efe4909da44726bad24cf7572ae338d7f"
 "checksum rand 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
@@ -521,7 +486,6 @@ dependencies = [
 "checksum unicode-segmentation 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e83e153d1053cbb5a118eeff7fd5be06ed99153f00dbcd8ae310c5fb2b22edc0"
 "checksum unicode-width 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
 "checksum unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
-"checksum unindent 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "63f18aa3b0e35fed5a0048f029558b1518095ffe2a0a31fb87c93dece93a4993"
 "checksum uuid 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "9fde2f6a4bea1d6e007c4ad38c6839fa71cbb63b6dbf5b595aa38dc9b1093c11"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum version_check 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "078775d0255232fb988e6fccf26ddc9d1ac274299aaedcedce21c6f72cc533ce"
diff --git a/Cargo.toml b/Cargo.toml
index be13607..0e635aa 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,7 +17,6 @@ anyhow = "1.0.27"
 bincode = "1.2.1"
 clap = "2.33.0"
 dirs = "2.0.2"
-indoc = "0.3.5"
 serde = { version = "1.0.105", features = ["derive"] }
 structopt = "0.3.12"
 uuid = { version = "0.8.1", features = ["v4"] }
diff --git a/src/db.rs b/src/db.rs
index 758865c..2af013c 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -2,7 +2,6 @@ use crate::config;
 use crate::dir::{Dir, Epoch, Rank};
 
 use anyhow::{anyhow, bail, Context, Result};
-use indoc::indoc;
 use serde::{Deserialize, Serialize};
 use uuid::Uuid;
 
@@ -96,10 +95,10 @@ impl DB {
 
     pub fn import<P: AsRef<Path>>(&mut self, path: P, merge: bool) -> Result<()> {
         if !self.data.dirs.is_empty() && !merge {
-            bail!(indoc!(
-                "To prevent conflicts, you can only import from z with an empty zoxide database!
-                If you wish to merge the two, specify the `--merge` flag."
-            ));
+            bail!(
+                "To prevent conflicts, you can only import from z with an empty zoxide database!\n\
+                 If you wish to merge the two, specify the `--merge` flag."
+            );
         }
 
         let z_db_file = File::open(path).context("could not open z database file")?;

From 3c7d100ab1ff7805444f6f64cb2339ccb4546e16 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Mon, 30 Mar 2020 03:04:39 +0530
Subject: [PATCH 14/16] Guarantee unique file names for temporary database

---
 src/db.rs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/db.rs b/src/db.rs
index 2af013c..e8f9e7e 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -6,7 +6,7 @@ use serde::{Deserialize, Serialize};
 use uuid::Uuid;
 
 use std::cmp::Ordering;
-use std::fs::{self, File};
+use std::fs::{self, File, OpenOptions};
 use std::io::{self, BufRead, BufReader, BufWriter};
 use std::path::{Path, PathBuf};
 
@@ -77,8 +77,12 @@ impl DB {
         if self.modified {
             let path_tmp = self.get_path_tmp();
 
-            let file_tmp =
-                File::create(&path_tmp).context("could not open temporary database file")?;
+            let file_tmp = OpenOptions::new()
+                .write(true)
+                // ensure that we are not overwriting an existing file_tmp
+                .create_new(true)
+                .open(&path_tmp)
+                .context("could not open temporary database file")?;
 
             let writer = BufWriter::new(&file_tmp);
             bincode::serialize_into(writer, &self.data).context("could not serialize database")?;

From ad96db844cddcf96d498240d977d9fc5d6ea27b6 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Mon, 30 Mar 2020 05:25:56 +0530
Subject: [PATCH 15/16] Add CHANGELOG.md

---
 CHANGELOG.md | 93 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 README.md    | 27 ++++++++-------
 2 files changed, 109 insertions(+), 11 deletions(-)
 create mode 100644 CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..6d37ff7
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,93 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [0.3.0] - 2020-03-30
+
+### Added
+
+- Automatic migration from `v0.2.x` databases.
+- `$_ZO_EXCLUDE_DIRS` to prevent certain directories from being added to the database.
+- Support for POSIX-compliant shells.
+
+### Changed
+
+- Database location defaults to user's local data directory.
+- Database schema now includes a version number.
+- `migrate` subcommand renamed to `import`.
+
+### Fixed
+
+- Achieve thread safety using unique temporary database file names for each `zoxide` instance.
+- Incomprehensive "could not allocate" message on database corruption.
+
+## [0.2.2] - 2020-03-20
+
+### Fixed
+
+- Incorrect exit codes in `z` command on `fish`.
+
+### Removed
+
+- File locks on database.
+
+## [0.2.1] - 2020-03-16
+
+### Added
+
+- `$_ZO_ECHO` to echo match before `cd`ing.
+- Minimal `ranger` plugin.
+- PWD hook to only update the database when the current directory is changed.
+- Support for the `bash` shell.
+- `migrate` subcommand to allow users to migrate from `z`.
+
+### Fixed
+
+- Interactive queries causing other open shells to hang.
+
+## [0.2.0] - 2020-03-11
+
+### Added
+
+- `init` subcommand to remove dependency on shell plugin managers.
+- Support for `z -` command to go to previous directory.
+- `Cargo.lock` for more reproducible builds.
+- Support for the `fish` shell.
+
+### Fixed
+
+- `_zoxide_precmd` overriding other precmd hooks on `zsh`.
+
+## [0.1.1] - 2020-03-08
+
+### Added
+
+- Install script for Linux/macOS users.
+- Aging algorithm to remove stale entries.
+
+### Changed
+
+- Database schema now uses `f64` values for rank instead of `i32`.
+
+### Fixed
+
+- Multiple hooks being added upon initializing `zoxide` multiple times.
+
+## [0.1.0] - 2020-03-05
+
+### Added
+
+- GitHub Actions pipeline to build and upload releases.
+- Support for the `zsh` shell.
+
+[0.3.0]: https://github.com/ajeetdsouza/zoxide/compare/v0.2.2...v0.3.0
+[0.2.2]: https://github.com/ajeetdsouza/zoxide/compare/v0.2.1...v0.2.2
+[0.2.1]: https://github.com/ajeetdsouza/zoxide/compare/v0.2.0...v0.2.1
+[0.2.0]: https://github.com/ajeetdsouza/zoxide/compare/v0.1.1...v0.2.0
+[0.1.1]: https://github.com/ajeetdsouza/zoxide/compare/v0.1.0...v0.1.1
+[0.1.0]: https://github.com/ajeetdsouza/zoxide/commits/v0.1.0
diff --git a/README.md b/README.md
index 6b59dda..516e2c6 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,10 @@ A cd command that learns your habits
 
 ## Introduction
 
-`zoxide` is a blazing fast alternative to `cd`, inspired by [`z`](https://github.com/rupa/z) and [`z.lua`](https://github.com/skywind3000/z.lua). It keeps track of the directories you use most frequently, and uses a ranking algorithm to navigate to the best match.
+`zoxide` is a blazing fast alternative to `cd`, inspired by
+[`z`](https://github.com/rupa/z) and [`z.lua`](https://github.com/skywind3000/z.lua).
+It keeps track of the directories you use most frequently, and uses a ranking algorithm
+to navigate to the best match.
 
 ## Examples
 
@@ -56,11 +59,13 @@ Otherwise, try the install script:
 curl --proto '=https' --tlsv1.2 -sSf https://raw.githubusercontent.com/ajeetdsouza/zoxide/master/install.sh | sh
 ```
 
-If you want the interactive fuzzy selection feature, you will also need to install [`fzf`](https://github.com/junegunn/fzf.git).
+If you want the interactive fuzzy selection feature, you will also need to install
+[`fzf`](https://github.com/junegunn/fzf.git).
 
 ### Step 2: Adding `zoxide` to your shell
 
-If you currently use `z`, `z.lua`, or `zsh-z`, you may want to first import your existing database into `zoxide`:
+If you currently use `z`, `z.lua`, or `zsh-z`, you may want to first import
+your existing database into `zoxide`:
 
 ```sh
 zoxide import /path/to/db
@@ -92,17 +97,17 @@ zoxide init fish | source
 
 #### POSIX
 
-Add the following line to your shell's configuration file (or, run it manually):
+Add the following line to your shell's configuration file:
 
-``` sh
+```sh
 eval "$(zoxide init posix)"
 ```
 
 NOTE: If you modify your `PS1` at any point, you may need to re-run the above command. This is due
-to the fact that we store our hook in `PS1`, in order to be evaluated every time the prompt is
+to the fact that the hook is stored in `PS1`, in order to be evaluated every time the prompt is
 displayed.
 
-NOTE: There is no PWD hook provided for POSIX shells.
+NOTE: PWD hooks are currently not supported for POSIX shells.
 
 ## Configuration
 
@@ -110,18 +115,18 @@ NOTE: There is no PWD hook provided for POSIX shells.
 
 - `--no-define-aliases`: don't define extra aliases like `zi`, `zq`, `za`, and `zr`
 - `--hook <HOOK>`: change the event that adds a new entry to the database (default: `prompt`)
-  - `none`: never add entries - this will make `zoxide` useless unless you manually configure a hook
+  - `none`: never add entries (this will make `zoxide` useless unless you manually configure a hook)
   - `prompt`: add an entry at every prompt
   - `pwd`: add an entry whenever you change directories
 
 ### Environment variables
 
 - `$_ZO_DATA_DIR`: directory where `zoxide` will store its data files (default:
-    platform-specific; see the [`dirs` documentation] for more information)
+  platform-specific; see the [`dirs` documentation] for more information)
 - `$_ZO_ECHO`: `z` will print the matched directory before navigating to it
 - `$_ZO_EXCLUDE_DIRS`: list of directories separated by platform-specific
-    characters (`:` on Linux and macOS, and `;` on Windows) to be excluded from
-    the database
+  characters ("`:`" on Linux and macOS, and "`;`" on Windows) to be excluded from
+  the database
 - `$_ZO_MAXAGE`: sets the maximum total rank after which entries start getting deleted
 
 [`dirs` documentation]: https://docs.rs/dirs/latest/dirs/fn.data_local_dir.html

From 9d0222383f9c517f2bf4bbaf9971af0397c94110 Mon Sep 17 00:00:00 2001
From: Ajeet D'Souza <98ajeet@gmail.com>
Date: Mon, 30 Mar 2020 06:49:41 +0530
Subject: [PATCH 16/16] Style nits

---
 src/config.rs           |  9 ++++-----
 src/db.rs               |  6 ++++--
 src/subcommand/query.rs | 10 +++++-----
 src/util.rs             | 15 ++++++++-------
 4 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/src/config.rs b/src/config.rs
index 2376fff..61ca135 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -13,14 +13,13 @@ pub const DB_VERSION: DBVersion = 3;
 pub fn zo_data_dir() -> Result<PathBuf> {
     let data_dir = match env::var_os("_ZO_DATA_DIR") {
         Some(data_osstr) => PathBuf::from(data_osstr),
-        None => {
-            if let Some(mut data_dir) = dirs::data_local_dir() {
+        None => match dirs::data_local_dir() {
+            Some(mut data_dir) => {
                 data_dir.push("zoxide");
                 data_dir
-            } else {
-                bail!("could not find database directory, please set _ZO_DATA_DIR manually");
             }
-        }
+            None => bail!("could not find database directory, please set _ZO_DATA_DIR manually"),
+        },
     };
 
     // This will fail when `data_dir` points to a file or a broken symlink, but
diff --git a/src/db.rs b/src/db.rs
index e8f9e7e..9e7c126 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -16,6 +16,7 @@ pub struct DB {
     data: DBData,
     modified: bool,
     path: PathBuf,
+    // FIXME: remove after next breaking version
     path_old: Option<PathBuf>,
 }
 
@@ -36,7 +37,7 @@ impl DB {
         };
 
         if data.version != config::DB_VERSION {
-            bail!("this database version ({}) is unsupported", data.version);
+            bail!("database version '{}' is unsupported", data.version);
         }
 
         Ok(DB {
@@ -47,6 +48,7 @@ impl DB {
         })
     }
 
+    // FIXME: remove after next breaking version
     pub fn open_and_migrate<P1, P2>(path_old: P1, path: P2) -> Result<DB>
     where
         P1: AsRef<Path>,
@@ -79,7 +81,6 @@ impl DB {
 
             let file_tmp = OpenOptions::new()
                 .write(true)
-                // ensure that we are not overwriting an existing file_tmp
                 .create_new(true)
                 .open(&path_tmp)
                 .context("could not open temporary database file")?;
@@ -280,6 +281,7 @@ impl Drop for DB {
         if let Err(e) = self.save() {
             eprintln!("{:#}", e);
         } else if let Some(path_old) = &self.path_old {
+            // FIXME: remove this branch after next breaking release
             if let Err(e) = fs::remove_file(path_old).context("could not remove old database") {
                 eprintln!("{:#}", e);
             }
diff --git a/src/subcommand/query.rs b/src/subcommand/query.rs
index cba97d1..187544c 100644
--- a/src/subcommand/query.rs
+++ b/src/subcommand/query.rs
@@ -49,14 +49,14 @@ impl Query {
             *keyword = keyword.to_lowercase();
         }
 
-        if let Some(dir) = util::get_db()?.query(&self.keywords, now) {
+        let path_opt = util::get_db()?.query(&self.keywords, now).map(|dir| {
             // `path_to_bytes` is guaranteed to succeed here since
             // the path has already been queried successfully
             let path_bytes = util::path_to_bytes(&dir.path).unwrap();
-            Ok(Some(path_bytes.to_vec()))
-        } else {
-            Ok(None)
-        }
+            path_bytes.to_vec()
+        });
+
+        Ok(path_opt)
     }
 
     fn query_interactive(&mut self) -> Result<Option<Vec<u8>>> {
diff --git a/src/util.rs b/src/util.rs
index 80dcccd..74614d5 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -13,6 +13,7 @@ use std::time::SystemTime;
 #[cfg(unix)]
 pub fn path_to_bytes<P: AsRef<Path>>(path: &P) -> Option<&[u8]> {
     use std::os::unix::ffi::OsStrExt;
+
     Some(path.as_ref().as_os_str().as_bytes())
 }
 
@@ -123,12 +124,12 @@ pub fn fzf_helper(now: Epoch, mut dirs: Vec<Dir>) -> Result<Option<Vec<u8>>> {
 #[inline]
 pub fn clamp(val: f64, min: f64, max: f64) -> f64 {
     assert!(min <= max);
-    let mut x = val;
-    if x < min {
-        x = min;
+
+    if val < min {
+        min
+    } else if val > max {
+        max
+    } else {
+        val
     }
-    if x > max {
-        x = max;
-    }
-    x
 }