WIP: Add mypy tests (#737)

* Add basic mypy tests

* Only run mypy on 3.6+

* No pypy

* Fix things

* Oooh parametrized

3 files changed, 32 insertions, 0 deletions

diff --git a/MANIFEST.in b/MANIFEST.in
index 46c9dbb..398252b 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -8,6 +8,7 @@ recursive-include src *.pyi
 # Tests
 include tox.ini conftest.py
 recursive-include tests *.py
+recursive-include tests *.yml
 
 # Documentation
 include docs/Makefile docs/docutils.conf
diff --git a/setup.py b/setup.py
index 51f4178..3215228 100644
--- a/setup.py
+++ b/setup.py
@@ -1,6 +1,8 @@
 import codecs
 import os
+import platform
 import re
+import sys
 
 from setuptools import find_packages, setup
 
@@ -50,6 +52,12 @@ EXTRAS_REQUIRE = {
         "six",
     ],
 }
+if (
+    sys.version_info[:2] >= (3, 6)
+    and platform.python_implementation() != "PyPy"
+):
+    EXTRAS_REQUIRE["tests_no_zope"].extend(["mypy", "pytest-mypy-plugins"])
+
 EXTRAS_REQUIRE["tests"] = EXTRAS_REQUIRE["tests_no_zope"] + ["zope.interface"]
 EXTRAS_REQUIRE["dev"] = (
     EXTRAS_REQUIRE["tests"] + EXTRAS_REQUIRE["docs"] + ["pre-commit"]
diff --git a/tests/test_mypy.yml b/tests/test_mypy.yml
new file mode 100644
index 0000000..18128e6
--- /dev/null
+++ b/tests/test_mypy.yml
@@ -0,0 +1,23 @@
+- case: attr_s_with_type_argument
+  parametrized:
+    - val: 'a = attr.ib(type=int)'
+    - val: 'a: int = attr.ib()'
+  main: |
+    import attr
+    @attr.s
+    class C:
+        {{ val }}
+    C()  # E: Too few arguments for "C"
+    C(1)
+    C(a=1)
+    C(a="hi")  # E: Argument "a" to "C" has incompatible type "str"; expected "int"
+- case: attr_s_with_type_annotations
+  main : |
+    import attr
+    @attr.s
+    class C:
+      a: int = attr.ib()
+    C()  # E: Too few arguments for "C"
+    C(1)
+    C(a=1)
+    C(a="hi")  # E: Argument "a" to "C" has incompatible type "str"; expected "int"