Follow review

* remove redundant type declarartions
* comment about aliasing
* s/AssertionFailure/AssertionError/g
* Fix comment in pytest.ini

Author: elazarg

mypy/test/data.py

@@ -658,12 +658,12 @@ def repr_failure(self, excinfo: Any) -> str:
 class DataSuite:
     # option fields - class variables
     files = None  # type: List[str]
-    base_path = '.'  # type: str
-    optional_out = False  # type: bool
-    native_sep = False  # type: bool
+    base_path = '.'
+    optional_out = False
+    native_sep = False
 
     # Assigned from MypyDataCase.runtest
-    update_data = False  # type: bool
+    update_data = False
 
     def setup(self) -> None:
         """Setup fixtures (ad-hoc)"""

mypy/test/helpers.py

@@ -8,6 +8,9 @@
 from mypy import defaults
 
 import pytest  # type: ignore  # no pytest in typeshed
+
+# Exporting Suite as alias to TestCase for backwards compatibility
+# TODO: avoid aliasing - import and subclass TestCase directly
 from unittest import TestCase as Suite
 
 from mypy.main import process_options
@@ -89,7 +92,7 @@ def assert_string_arrays_equal(expected: List[str], actual: List[str],
             # long lines.
             show_align_message(expected[first_diff], actual[first_diff])
 
-        raise AssertionFailure(msg)
+        raise AssertionError(msg)
 
 
 def update_testcase_output(testcase: DataDrivenTestCase, output: List[str]) -> None:
@@ -254,24 +257,17 @@ def retry_on_error(func: Callable[[], Any], max_wait: float = 1.0) -> None:
                 raise
             time.sleep(wait_time)
 
-
-class AssertionFailure(Exception):
-    """Exception used to signal failed test cases."""
-    def __init__(self, s: Optional[str] = None) -> None:
-        if s:
-            super().__init__(s)
-        else:
-            super().__init__()
+# TODO: assert_true and assert_false are redundant - use plain assert
 
 
 def assert_true(b: bool, msg: Optional[str] = None) -> None:
     if not b:
-        raise AssertionFailure(msg)
+        raise AssertionError(msg)
 
 
 def assert_false(b: bool, msg: Optional[str] = None) -> None:
     if b:
-        raise AssertionFailure(msg)
+        raise AssertionError(msg)
 
 
 def good_repr(obj: object) -> str:
@@ -288,7 +284,7 @@ def good_repr(obj: object) -> str:
 
 def assert_equal(a: object, b: object, fmt: str = '{} != {}') -> None:
     if a != b:
-        raise AssertionFailure(fmt.format(good_repr(a), good_repr(b)))
+        raise AssertionError(fmt.format(good_repr(a), good_repr(b)))
 
 
 def typename(t: type) -> str:
@@ -300,7 +296,7 @@ def typename(t: type) -> str:
 
 def assert_type(typ: type, value: object) -> None:
     if type(value) != typ:
-        raise AssertionFailure('Invalid type {}, expected {}'.format(
+        raise AssertionError('Invalid type {}, expected {}'.format(
             typename(type(value)), typename(typ)))
 
 

mypy/test/testcheck.py

@@ -11,7 +11,7 @@
 from mypy.test.config import test_temp_dir
 from mypy.test.data import DataDrivenTestCase, DataSuite
 from mypy.test.helpers import (
-    assert_string_arrays_equal, normalize_error_messages, AssertionFailure,
+    assert_string_arrays_equal, normalize_error_messages,
     retry_on_error, update_testcase_output, parse_options
 )
 from mypy.errors import CompileError
@@ -245,8 +245,8 @@ def verify_cache(self, module_data: List[Tuple[str, str, str]], a: List[str],
         modules.update({module_name: path for module_name, path, text in module_data})
         missing_paths = self.find_missing_cache_files(modules, manager)
         if not missing_paths.issubset(error_paths):
-            raise AssertionFailure("cache data discrepancy %s != %s" %
-                                   (missing_paths, error_paths))
+            raise AssertionError("cache data discrepancy %s != %s" %
+                                 (missing_paths, error_paths))
 
     def find_error_paths(self, a: List[str]) -> Set[str]:
         hits = set()

mypy/test/testcmdline.py

@@ -11,7 +11,6 @@
 
 from typing import List
 
-from mypy.test.helpers import AssertionFailure
 from mypy.test.config import test_temp_dir
 from mypy.test.data import fix_cobertura_filename
 from mypy.test.data import DataDrivenTestCase, DataSuite
@@ -65,7 +64,7 @@ def test_python_cmdline(testcase: DataDrivenTestCase) -> None:
     if testcase.output_files:
         for path, expected_content in testcase.output_files:
             if not os.path.exists(path):
-                raise AssertionFailure(
+                raise AssertionError(
                     'Expected file {} was not produced by test case'.format(path))
             with open(path, 'r') as output_file:
                 actual_output_content = output_file.read().splitlines()

mypy/test/testdmypy.py

@@ -13,7 +13,7 @@
 from mypy.test.config import test_temp_dir
 from mypy.test.data import DataDrivenTestCase, DataSuite, has_stable_flags, is_incremental
 from mypy.test.helpers import (
-    assert_string_arrays_equal, normalize_error_messages, AssertionFailure,
+    assert_string_arrays_equal, normalize_error_messages,
     retry_on_error, testcase_pyversion, update_testcase_output,
 )
 from mypy.options import Options
@@ -194,8 +194,8 @@ def verify_cache(self, module_data: List[Tuple[str, str, Optional[str]]], a: Lis
         modules.update({module_name: path for module_name, path, text in module_data})
         missing_paths = self.find_missing_cache_files(modules, manager)
         if not missing_paths.issubset(error_paths):
-            raise AssertionFailure("cache data discrepancy %s != %s" %
-                                   (missing_paths, error_paths))
+            raise AssertionError("cache data discrepancy %s != %s" %
+                                 (missing_paths, error_paths))
 
     def find_error_paths(self, a: List[str]) -> Set[str]:
         hits = set()

mypy/test/testerrorstream.py

@@ -5,7 +5,7 @@
 
 from mypy import defaults, build
 from mypy.test.config import test_temp_dir
-from mypy.test.helpers import assert_string_arrays_equal, AssertionFailure
+from mypy.test.helpers import assert_string_arrays_equal
 from mypy.test.data import DataDrivenTestCase, DataSuite
 from mypy.build import BuildSource
 from mypy.errors import CompileError

mypy/test/testparse.py

@@ -1,7 +1,7 @@
 """Tests for the mypy parser."""
 
 from mypy import defaults
-from mypy.test.helpers import assert_string_arrays_equal, AssertionFailure
+from mypy.test.helpers import assert_string_arrays_equal
 from mypy.test.data import DataDrivenTestCase, DataSuite
 from mypy.parse import parse
 from mypy.errors import CompileError
@@ -59,7 +59,7 @@ def test_parse_error(testcase: DataDrivenTestCase) -> None:
         # Compile temporary file. The test file contains non-ASCII characters.
         parse(bytes('\n'.join(testcase.input), 'utf-8'), INPUT_FILE_NAME, '__main__', None,
               Options())
-        raise AssertionFailure('No errors reported')
+        raise AssertionError('No errors reported')
     except CompileError as e:
         assert e.module_with_blocker == '__main__'
         # Verify that there was a compile error and that the error messages

mypy/test/testtransform.py

@@ -63,7 +63,7 @@ def test_transform(testcase: DataDrivenTestCase) -> None:
                     and not os.path.basename(f.path).startswith('_')
                     and not os.path.splitext(
                         os.path.basename(f.path))[0].endswith('_')):
-                t = TestTransformVisitor()
+                t = TypeAssertTransformVisitor()
                 f = t.mypyfile(f)
                 a += str(f).split('\n')
     except CompileError as e:
@@ -75,7 +75,7 @@ def test_transform(testcase: DataDrivenTestCase) -> None:
                                                                 testcase.line))
 
 
-class TestTransformVisitor(TransformVisitor):
+class TypeAssertTransformVisitor(TransformVisitor):
     def type(self, type: Type) -> Type:
         assert type is not None
         return type

pytest.ini

@@ -12,9 +12,11 @@ python_files = test*.py
 # and invokes it at the relevant moment.  See
 # http://doc.pytest.org/en/latest/writing_plugins.html#collection-hooks
 
-# Because we provide our own collection logic, disable the default
-# python collector by giving it empty patterns to search for.
-python_classes = *Suite
+# Both our plugin and unittest provide their own collection logic,
+# So we can disable the default python collector by giving it empty
+# patterns to search for.
+# Note that unittest requires that no "Test*" classes exist.
+python_classes =
 python_functions =
 
 # always run in parallel (requires pytest-xdist, see test-requirements.txt)