🔧 --no-showlocals to negate addopts w/ --showlocals

changelog/10381.improvement.rst

@@ -0,0 +1 @@
+The ``--no-showlocals`` flag has been added. This can be passed directly to tests to override ``--showlocals`` declared through ``addopts``.

doc/en/how-to/output.rst

@@ -12,8 +12,9 @@ Examples for modifying traceback printing:
 
 .. code-block:: bash
 
-    pytest --showlocals # show local variables in tracebacks
-    pytest -l           # show local variables (shortcut)
+    pytest --showlocals     # show local variables in tracebacks
+    pytest -l               # show local variables (shortcut)
+    pytest --no-showlocals  # hide local variables (if addopts enables them)
 
     pytest --tb=auto    # (default) 'long' tracebacks for the first and last
                          # entry, but 'short' style for the other entries

src/_pytest/terminal.py

@@ -178,6 +178,12 @@ def pytest_addoption(parser: Parser) -> None:
         default=False,
         help="Show locals in tracebacks (disabled by default)",
     )
+    group._addoption(
+        "--no-showlocals",
+        action="store_false",
+        dest="showlocals",
+        help="Hide locals in tracebacks (negate --showlocals passed through addopts)",
+    )
     group._addoption(
         "--tb",
         metavar="style",

testing/test_terminal.py

@@ -998,6 +998,22 @@ def test_showlocals():
             ]
         )
 
+    def test_noshowlocals_addopts_override(self, pytester: Pytester) -> None:
+        pytester.makeini("[pytest]\naddopts=--showlocals")
+        p1 = pytester.makepyfile(
+            """
+            def test_noshowlocals():
+                x = 3
+                y = "x" * 5000
+                assert 0
+        """
+        )
+
+        # Override global --showlocals for py.test via arg
+        result = pytester.runpytest(p1, "--no-showlocals")
+        result.stdout.no_fnmatch_line("x* = 3")
+        result.stdout.no_fnmatch_line("y* = 'xxxxxx*")
+
     def test_showlocals_short(self, pytester: Pytester) -> None:
         p1 = pytester.makepyfile(
             """