#7938 - [Plugin: Stepwise][Enhancements] Refactoring, smarter registration & --sw-skip functionality

changelog/7938.improvement.rst

@@ -0,0 +1 @@
+Stepwise plugin improvements and a new ``--sw-skip`` shorthand argument is now available

src/_pytest/stepwise.py

@@ -1,5 +1,6 @@
 from typing import List
 from typing import Optional
+from typing import TYPE_CHECKING
 
 import pytest
 from _pytest import nodes
@@ -8,53 +9,70 @@
 from _pytest.main import Session
 from _pytest.reports import TestReport
 
+if TYPE_CHECKING:
+    from _pytest.cacheprovider import Cache
+
+STEPWISE_CACHE_DIR = "cache/stepwise"
+NO_PREVIOUSLY_FAILED_WONT_SKIP = "no previously failed tests, not skipping."
+PREVIOUSLY_FAILED_TEST_NOT_FOUND = "previously failed test not found, not skipping."
+SKIPPING_PASSED_ITEMS = "skipping {} already passed items."
+
 
 def pytest_addoption(parser: Parser) -> None:
     group = parser.getgroup("general")
     group.addoption(
         "--sw",
         "--stepwise",
         action="store_true",
+        default=False,
         dest="stepwise",
         help="exit on test failure and continue from last failing test next time",
     )
     group.addoption(
         "--stepwise-skip",
+        "--sw-skip",
         action="store_true",
+        default=False,
         dest="stepwise_skip",
         help="ignore the first failing test but stop on the next failing test",
     )
 
 
 @pytest.hookimpl
 def pytest_configure(config: Config) -> None:
-    config.pluginmanager.register(StepwisePlugin(config), "stepwiseplugin")
+    # We should always have a cache as cache provider plugin uses tryfirst=True
+    if config.option.stepwise:
+        config.pluginmanager.register(StepwisePlugin(config), "stepwiseplugin")
+
+
+def pytest_sessionfinish(session: Session) -> None:
+    config = session.config
+    assert config.cache is not None
+    if not config.option.stepwise:
+        # This hook exists so that --cache-show when empty will not output the empty [] for stepwise by default.
+        # Perhaps this is ok to set in the unconfigure hook?  But I added it here to avoid changing behaviour.
+        config.cache.set(STEPWISE_CACHE_DIR, [])
 
 
 class StepwisePlugin:
     def __init__(self, config: Config) -> None:
         self.config = config
-        self.active = config.getvalue("stepwise")
         self.session: Optional[Session] = None
         self.report_status = ""
-
-        if self.active:
-            assert config.cache is not None
-            self.lastfailed = config.cache.get("cache/stepwise", None)
-            self.skip = config.getvalue("stepwise_skip")
+        assert config.cache is not None
+        self.cache: Cache = config.cache
+        self.lastfailed: Optional[str] = self.cache.get(STEPWISE_CACHE_DIR, None)
+        self.skip: bool = config.option.stepwise_skip
 
     def pytest_sessionstart(self, session: Session) -> None:
         self.session = session
 
     def pytest_collection_modifyitems(
-        self, session: Session, config: Config, items: List[nodes.Item]
+        self, config: Config, items: List[nodes.Item]
     ) -> None:
-        if not self.active:
-            return
         if not self.lastfailed:
-            self.report_status = "no previously failed tests, not skipping."
+            self.report_status = NO_PREVIOUSLY_FAILED_WONT_SKIP
             return
-
         already_passed = []
         found = False
 
@@ -65,26 +83,20 @@ def pytest_collection_modifyitems(
                 break
             else:
                 already_passed.append(item)
-
         # If the previously failed test was not found among the test items,
         # do not skip any tests.
         if not found:
-            self.report_status = "previously failed test not found, not skipping."
+            self.report_status = PREVIOUSLY_FAILED_TEST_NOT_FOUND
             already_passed = []
         else:
-            self.report_status = "skipping {} already passed items.".format(
-                len(already_passed)
-            )
+            self.report_status = SKIPPING_PASSED_ITEMS.format(len(already_passed))
 
         for item in already_passed:
             items.remove(item)
 
         config.hook.pytest_deselected(items=already_passed)
 
     def pytest_runtest_logreport(self, report: TestReport) -> None:
-        if not self.active:
-            return
-
         if report.failed:
             if self.skip:
                 # Remove test from the failed ones (if it exists) and unset the skip option
@@ -109,14 +121,9 @@ def pytest_runtest_logreport(self, report: TestReport) -> None:
                     self.lastfailed = None
 
     def pytest_report_collectionfinish(self) -> Optional[str]:
-        if self.active and self.config.getoption("verbose") >= 0 and self.report_status:
-            return "stepwise: %s" % self.report_status
+        if self.config.getoption("verbose") >= 0 and self.report_status:
+            return f"stepwise: {self.report_status}"
         return None
 
-    def pytest_sessionfinish(self, session: Session) -> None:
-        assert self.config.cache is not None
-        if self.active:
-            self.config.cache.set("cache/stepwise", self.lastfailed)
-        else:
-            # Clear the list of failing tests if the plugin is not active.
-            self.config.cache.set("cache/stepwise", [])
+    def pytest_sessionfinish(self) -> None:
+        self.cache.set(STEPWISE_CACHE_DIR, self.lastfailed)

testing/test_stepwise.py

@@ -117,14 +117,10 @@ def test_fail_and_continue_with_stepwise(stepwise_testdir):
     assert "test_success_after_fail PASSED" in stdout
 
 
-def test_run_with_skip_option(stepwise_testdir):
+@pytest.mark.parametrize("sw_option", ["--stepwise-skip", "--sw-skip"])
+def test_run_with_skip_option(stepwise_testdir, sw_option):
     result = stepwise_testdir.runpytest(
-        "-v",
-        "--strict-markers",
-        "--stepwise",
-        "--stepwise-skip",
-        "--fail",
-        "--fail-last",
+        "-v", "--strict-markers", "--stepwise", f"{sw_option}", "--fail", "--fail-last",
     )
     assert _strip_resource_warnings(result.stderr.lines) == []