gh-117294: Report DocTestCase as skipped if all examples in the doctest are skipped (GH-117297)

Lib/doctest.py

@@ -2281,12 +2281,13 @@ def runTest(self):
 
         try:
             runner.DIVIDER = "-"*70
-            failures, tries = runner.run(
-                test, out=new.write, clear_globs=False)
+            results = runner.run(test, out=new.write, clear_globs=False)
+            if results.skipped == results.attempted:
+                raise unittest.SkipTest("all examples were skipped")
         finally:
             sys.stdout = old
 
-        if failures:
+        if results.failed:
             raise self.failureException(self.format_failure(new.getvalue()))
 
     def format_failure(self, err):

Lib/test/test_doctest/sample_doctest_skip.py

@@ -0,0 +1,49 @@
+"""This is a sample module used for testing doctest.
+
+This module includes various scenarios involving skips.
+"""
+
+def no_skip_pass():
+    """
+    >>> 2 + 2
+    4
+    """
+
+def no_skip_fail():
+    """
+    >>> 2 + 2
+    5
+    """
+
+def single_skip():
+    """
+    >>> 2 + 2  # doctest: +SKIP
+    4
+    """
+
+def double_skip():
+    """
+    >>> 2 + 2  # doctest: +SKIP
+    4
+    >>> 3 + 3  # doctest: +SKIP
+    6
+    """
+
+def partial_skip_pass():
+    """
+    >>> 2 + 2  # doctest: +SKIP
+    4
+    >>> 3 + 3
+    6
+    """
+
+def partial_skip_fail():
+    """
+    >>> 2 + 2  # doctest: +SKIP
+    4
+    >>> 2 + 2
+    5
+    """
+
+def no_examples():
+    """A docstring with no examples should not be counted as run or skipped."""

Lib/test/test_doctest/test_doctest.py

@@ -2247,6 +2247,16 @@ def test_DocTestSuite():
          >>> suite.run(unittest.TestResult())
          <unittest.result.TestResult run=0 errors=0 failures=0>
 
+       If all examples in a docstring are skipped, unittest will report it as a
+       skipped test:
+
+         >>> suite = doctest.DocTestSuite('test.test_doctest.sample_doctest_skip')
+         >>> result = suite.run(unittest.TestResult())
+         >>> result
+         <unittest.result.TestResult run=6 errors=0 failures=2>
+        >>> len(result.skipped)
+        2
+
        We can use the current module:
 
          >>> suite = test.test_doctest.sample_doctest.test_suite()
@@ -2418,6 +2428,18 @@ def test_DocFileSuite():
          Traceback (most recent call last):
          ValueError: Package may only be specified for module-relative paths.
 
+       If all examples in a file are skipped, unittest will report it as a
+       skipped test:
+
+         >>> suite = doctest.DocFileSuite('test_doctest.txt',
+         ...                              'test_doctest4.txt',
+         ...                              'test_doctest_skip.txt')
+         >>> result = suite.run(unittest.TestResult())
+         >>> result
+         <unittest.result.TestResult run=3 errors=0 failures=1>
+        >>> len(result.skipped)
+        1
+
        You can specify initial global variables:
 
          >>> suite = doctest.DocFileSuite('test_doctest.txt',

Lib/test/test_doctest/test_doctest_skip.txt

@@ -0,0 +1,4 @@
+This is a sample doctest in a text file, in which all examples are skipped.
+
+  >>> 2 + 2  # doctest: +SKIP
+  5

Lib/test/test_zipimport_support.py

@@ -31,7 +31,7 @@
 # Retrieve some helpers from other test cases
 from test.test_doctest import (test_doctest,
                                sample_doctest, sample_doctest_no_doctests,
-                               sample_doctest_no_docstrings)
+                               sample_doctest_no_docstrings, sample_doctest_skip)
 
 
 def _run_object_doctest(obj, module):
@@ -110,7 +110,7 @@ def test_doctest_issue4197(self):
         # The sample doctest files rewritten to include in the zipped version.
         sample_sources = {}
         for mod in [sample_doctest, sample_doctest_no_doctests,
-                    sample_doctest_no_docstrings]:
+                    sample_doctest_no_docstrings, sample_doctest_skip]:
             src = inspect.getsource(mod)
             src = src.replace("test.test_doctest.test_doctest", "test_zipped_doctest")
             # Rewrite the module name so that, for example,