Add mypy tests.

tests_typing/test_http_request.mypy-testing

@@ -0,0 +1,66 @@
+import pytest
+
+from scrapy import Request
+from scrapy.http import JsonRequest
+
+
+class MyRequest(Request):
+    pass
+
+
+class MyRequest2(Request):
+    pass
+
+
+@pytest.mark.mypy_testing
+def mypy_test_headers():
+    Request("data:,", headers=1)  # E: Argument "headers" to "Request" has incompatible type "int"; expected "Mapping[str, Any] | Iterable[tuple[str, Any]] | None"
+    Request("data:,", headers=None)
+    Request("data:,", headers={})
+    Request("data:,", headers=[])
+    Request("data:,", headers={"foo": "bar"})
+    Request("data:,", headers={b"foo": "bar"})
+    Request("data:,", headers={"foo": b"bar"})
+    Request("data:,", headers=[("foo", "bar")])
+    Request("data:,", headers=[(b"foo", "bar")])
+    Request("data:,", headers=[("foo", b"bar")])
+
+
+@pytest.mark.mypy_testing
+def mypy_test_copy():
+    req = Request("data:,")
+    reveal_type(req)  # R: scrapy.http.request.Request
+    req_copy = req.copy()
+    reveal_type(req_copy)  # R: scrapy.http.request.Request
+
+    req = MyRequest("data:,")
+    reveal_type(req)  # R: __main__.MyRequest
+    req_copy = req.copy()
+    reveal_type(req_copy)  # R: __main__.MyRequest
+
+
+@pytest.mark.mypy_testing
+def mypy_test_replace():
+    req = Request("data:,")
+    reveal_type(req)  # R: scrapy.http.request.Request
+    req_copy = req.replace(body=b"a")
+    reveal_type(req_copy)  # R: scrapy.http.request.Request
+
+    req = MyRequest("data:,")
+    reveal_type(req)  # R: __main__.MyRequest
+    req_copy = req.replace(body=b"a")
+    reveal_type(req_copy)  # R: __main__.MyRequest
+    req_copy2 = req.replace(body=b"a", cls=MyRequest2)
+    reveal_type(req_copy2)  # R: __main__.MyRequest2
+
+
+@pytest.mark.mypy_testing
+def mypy_test_jsonrequest_copy_replace():
+    req = JsonRequest("data:,")
+    reveal_type(req)  # R: scrapy.http.request.json_request.JsonRequest
+    req_copy = req.copy()
+    reveal_type(req_copy)  # R: scrapy.http.request.json_request.JsonRequest
+    req_copy = req.replace(body=b"a")
+    reveal_type(req_copy)  # R: scrapy.http.request.json_request.JsonRequest
+    req_copy_my = req.replace(body=b"a", cls=MyRequest)
+    reveal_type(req_copy_my)  # R: __main__.MyRequest

tests_typing/test_http_response.mypy-testing

@@ -0,0 +1,45 @@
+import pytest
+
+from scrapy.http import HtmlResponse, Response, TextResponse
+
+
+@pytest.mark.mypy_testing
+def mypy_test_headers():
+    Response("data:,", headers=1)  # E: Argument "headers" to "Response" has incompatible type "int"; expected "Mapping[str, Any] | Iterable[tuple[str, Any]] | None"
+    Response("data:,", headers=None)
+    Response("data:,", headers={})
+    Response("data:,", headers=[])
+    Response("data:,", headers={"foo": "bar"})
+    Response("data:,", headers={b"foo": "bar"})
+    Response("data:,", headers={"foo": b"bar"})
+    Response("data:,", headers=[("foo", "bar")])
+    Response("data:,", headers=[(b"foo", "bar")])
+    Response("data:,", headers=[("foo", b"bar")])
+
+
+@pytest.mark.mypy_testing
+def mypy_test_copy():
+    resp = Response("data:,")
+    reveal_type(resp)  # R: scrapy.http.response.Response
+    resp_copy = resp.copy()
+    reveal_type(resp_copy)  # R: scrapy.http.response.Response
+
+    resp = HtmlResponse("data:,")
+    reveal_type(resp)  # R: scrapy.http.response.html.HtmlResponse
+    resp_copy = resp.copy()
+    reveal_type(resp_copy)  # R: scrapy.http.response.html.HtmlResponse
+
+
+@pytest.mark.mypy_testing
+def mypy_test_replace():
+    resp = Response("data:,")
+    reveal_type(resp)  # R: scrapy.http.response.Response
+    resp_copy = resp.replace(body=b"a")
+    reveal_type(resp_copy)  # R: scrapy.http.response.Response
+
+    resp = HtmlResponse("data:,")
+    reveal_type(resp)  # R: scrapy.http.response.html.HtmlResponse
+    resp_copy = resp.replace(body=b"a")
+    reveal_type(resp_copy)  # R: scrapy.http.response.html.HtmlResponse
+    resp_copy2 = resp.replace(body=b"a", cls=TextResponse)
+    reveal_type(resp_copy2)  # R: scrapy.http.response.text.TextResponse

tox.ini

@@ -46,6 +46,14 @@ deps =
 commands =
     mypy {posargs: scrapy tests}
 
+[testenv:typing-tests]
+deps =
+    {[testenv]deps}
+    {[testenv:typing]deps}
+    pytest-mypy-testing==0.1.1
+commands =
+    pytest {posargs: tests_typing}
+
 [testenv:pre-commit]
 basepython = python3
 deps =