Massively refactor the test suite (#229)

Signed-off-by: Edward Z. Yang <[email protected]>

.flake8

@@ -14,7 +14,8 @@ max-line-length = 120
 # P208 is a duplicate of C403.
 # W503 talks about operator formatting which is too opinionated.
 # C901 I like long functions
-ignore = E127, E128, E203, E265, E266, E402, E501, E722, P207, P208, W503, C901
+# F403 should turn this on for ghstack/, lookup exclude format TODO
+ignore = E127, E128, E203, E265, E266, E402, E501, E722, P207, P208, W503, C901, F403, F405
 exclude =
   .git,
   .hg,

.gitignore

@@ -8,3 +8,6 @@ build
 .python-version
 .venv/
 .vscode
+tags
+*.log
+plan.txt

.lintrunner.toml

@@ -2,7 +2,7 @@ merge_base_with = "origin/master"
 
 [[linter]]
 code = 'FLAKE8'
-include_patterns = ['**/*.py']
+include_patterns = ['**/*.py', '**/*.py.test']
 command = [
     'python3',
     'tools/linter/adapters/flake8_linter.py',
@@ -13,8 +13,8 @@ command = [
 
 [[linter]]
 code = 'MYPY'
-include_patterns = ['**/*.py']
-exclude_patterns = ['tools/**']
+include_patterns = ['**/*.py', '**/*.py.test']
+exclude_patterns = ['tools/**', 'conftest.py']
 command = [
     'python3',
     'tools/linter/adapters/mypy_linter.py',
@@ -25,7 +25,7 @@ command = [
 
 [[linter]]
 code = 'UFMT'
-include_patterns = ['**/*.py', '**/*.pyi']
+include_patterns = ['**/*.py', '**/*.pyi', '**/*.py.test']
 command = [
     'python3',
     'tools/linter/adapters/ufmt_linter.py',

conftest.py

@@ -0,0 +1,42 @@
+# mypy: ignore-errors
+
+import pathlib
+import runpy
+
+import expecttest
+
+import ghstack.test_prelude
+
+import pytest
+
+
+# Adapted from https://stackoverflow.com/questions/56807698/how-to-run-script-as-pytest-test
+
+
+def pytest_collect_file(file_path: pathlib.Path, parent):
+    # NB: script name must not end with py, due to doctest picking it
+    # up in that case
+    if file_path.suffixes == [".py", ".test"]:
+        return Script.from_parent(parent, path=file_path)
+
+
+class Script(pytest.File):
+    def collect(self):
+        yield ScriptItem.from_parent(self, name="default", direct=False)
+        if self.path.parent.name in ["submit", "unlink"]:
+            yield ScriptItem.from_parent(self, name="direct", direct=True)
+
+
+class ScriptItem(pytest.Item):
+    def __init__(self, *, direct, **kwargs):
+        super().__init__(**kwargs)
+        self.direct = direct
+
+    def runtest(self):
+        with ghstack.test_prelude.scoped_test(direct=self.direct):
+            expecttest.EDIT_HISTORY.reload_file(self.fspath)
+            runpy.run_path(self.fspath)
+
+    def repr_failure(self, excinfo):
+        excinfo.traceback = excinfo.traceback.cut(path=self.fspath)
+        return super().repr_failure(excinfo)