Normalize extra names passed in (#2668)

Resolves https://github.com/tox-dev/tox/issues/2655

3 files changed, 32 insertions, 0 deletions

diff --git a/docs/changelog/2655.bugfix.rst b/docs/changelog/2655.bugfix.rst
new file mode 100644
index 00000000..88fa3003
--- /dev/null
+++ b/docs/changelog/2655.bugfix.rst
@@ -0,0 +1 @@
+Normalize extra names passed in (fixes extra groups not being picked up during installation) - by :user:`gaborbernat`.
diff --git a/src/tox/tox_env/python/runner.py b/src/tox/tox_env/python/runner.py
index 591633d7..785c4698 100644
--- a/src/tox/tox_env/python/runner.py
+++ b/src/tox/tox_env/python/runner.py
@@ -6,6 +6,8 @@ from __future__ import annotations
 from functools import partial
 from typing import Set
 
+from packaging.utils import canonicalize_name
+
 from tox.report import HandledError
 from tox.tox_env.errors import Skip
 from tox.tox_env.package import Package
@@ -65,11 +67,18 @@ class PythonRun(Python, RunToxEnv):
         pkg_type = self.pkg_type
         if pkg_type == "skip":
             return False
+
+        def _normalize_extras(values: set[str]) -> set[str]:
+            # although _ and . is allowed this will be normalized during packaging to -
+            # https://packaging.python.org/en/latest/specifications/dependency-specifiers/#grammar
+            return {canonicalize_name(v) for v in values}
+
         self.conf.add_config(
             keys=["extras"],
             of_type=Set[str],
             default=set(),
             desc="extras to install of the target package",
+            post_process=_normalize_extras,
         )
         return True
 
diff --git a/tests/tox_env/python/test_python_runner.py b/tests/tox_env/python/test_python_runner.py
index 797ad638..93d5e497 100644
--- a/tests/tox_env/python/test_python_runner.py
+++ b/tests/tox_env/python/test_python_runner.py
@@ -2,6 +2,8 @@ from __future__ import annotations
 
 from pathlib import Path
 
+import pytest
+
 from tox.journal import EnvJournal
 from tox.pytest import ToxProjectCreator
 from tox.tox_env.package import PathPackage
@@ -99,3 +101,23 @@ def test_package_temp_dir_view(tox_project: ToxProjectCreator, demo_pkg_inline:
     msg = f" D package {session_path} links to {Path('.pkg') / 'dist'/ wheel_name} ({project.path/ '.tox'}) "
     assert msg in result.out
     assert f" D delete package {project.path / '.tox' / session_path}" in result.out
+
+
+@pytest.mark.parametrize(
+    ("extra", "used_extra"),
+    [
+        ("d_oc", "d-oc"),
+        ("d-oc", "d-oc"),
+        ("d.oc", "d-oc"),
+    ],
+)
+def test_extras_are_normalized(
+    tox_project: ToxProjectCreator,
+    demo_pkg_inline: Path,
+    extra: str,
+    used_extra: str,
+) -> None:
+    project = tox_project({"tox.ini": f"[testenv]\nextras={extra}"})
+    result = project.run("c", "-e", "py", "--root", str(demo_pkg_inline), "-k", "extras")
+    result.assert_success()
+    assert result.out == f"[testenv:py]\nextras = {used_extra}\n"