pre-commit · asottile · Nov 8, 2025 · Nov 8, 2025
diff --git a/pre_commit/all_languages.py b/pre_commit/all_languages.py
@@ -19,9 +19,9 @@
 from pre_commit.languages import r
 from pre_commit.languages import ruby
 from pre_commit.languages import rust
-from pre_commit.languages import script
 from pre_commit.languages import swift
-from pre_commit.languages import system
+from pre_commit.languages import unsupported
+from pre_commit.languages import unsupported_script
 
 
 languages: dict[str, Language] = {
@@ -43,8 +43,8 @@
     'r': r,
     'ruby': ruby,
     'rust': rust,
-    'script': script,
     'swift': swift,
-    'system': system,
+    'unsupported': unsupported,
+    'unsupported_script': unsupported_script,
 }
 language_names = sorted(languages)
diff --git a/pre_commit/clientlib.py b/pre_commit/clientlib.py
@@ -6,6 +6,7 @@
 import re
 import shlex
 import sys
+from collections.abc import Callable
 from collections.abc import Sequence
 from typing import Any
 from typing import NamedTuple
@@ -190,6 +191,42 @@ def remove_default(self, dct: dict[str, Any]) -> None:
         raise NotImplementedError
 
 
+def _translate_language(name: str) -> str:
+    return {
+        'system': 'unsupported',
+        'script': 'unsupported_script',
+    }.get(name, name)
+
+
+class LanguageMigration(NamedTuple):  # remove
+    key: str
+    check_fn: Callable[[object], None]
+
+    def check(self, dct: dict[str, Any]) -> None:
+        if self.key not in dct:
+            return
+
+        with cfgv.validate_context(f'At key: {self.key}'):
+            self.check_fn(_translate_language(dct[self.key]))
+
+    def apply_default(self, dct: dict[str, Any]) -> None:
+        if self.key not in dct:
+            return
+
+        dct[self.key] = _translate_language(dct[self.key])
+
+    def remove_default(self, dct: dict[str, Any]) -> None:
+        raise NotImplementedError
+
+
+class LanguageMigrationRequired(LanguageMigration):  # replace with Required
+    def check(self, dct: dict[str, Any]) -> None:
+        if self.key not in dct:
+            raise cfgv.ValidationError(f'Missing required key: {self.key}')
+
+        super().check(dct)
+
+
 MANIFEST_HOOK_DICT = cfgv.Map(
     'Hook', 'id',
 
@@ -203,7 +240,7 @@ def remove_default(self, dct: dict[str, Any]) -> None:
     cfgv.Required('id', cfgv.check_string),
     cfgv.Required('name', cfgv.check_string),
     cfgv.Required('entry', cfgv.check_string),
-    cfgv.Required('language', cfgv.check_one_of(language_names)),
+    LanguageMigrationRequired('language', cfgv.check_one_of(language_names)),
     cfgv.Optional('alias', cfgv.check_string, ''),
 
     cfgv.Optional('files', check_string_regex, ''),
@@ -368,8 +405,10 @@ def check(self, dct: dict[str, Any]) -> None:
     'Hook', 'id',
     cfgv.Required('id', cfgv.check_string),
     cfgv.Required('id', cfgv.check_one_of(tuple(k for k, _ in _meta))),
-    # language must be system
-    cfgv.Optional('language', cfgv.check_one_of({'system'}), 'system'),
+    # language must be `unsupported`
+    cfgv.Optional(
+        'language', cfgv.check_one_of({'unsupported'}), 'unsupported',
+    ),
     # entry cannot be overridden
     NotAllowed('entry', cfgv.check_any),
     *(
@@ -402,8 +441,10 @@ def check(self, dct: dict[str, Any]) -> None:
         for item in MANIFEST_HOOK_DICT.items
         if item.key != 'id'
         if item.key != 'stages'
+        if item.key != 'language'  # remove
     ),
     StagesMigrationNoDefault('stages', []),
+    LanguageMigration('language', cfgv.check_one_of(language_names)),  # remove
     *_COMMON_HOOK_WARNINGS,
 )
 LOCAL_HOOK_DICT = cfgv.Map(

diff --git a/pre_commit/languages/system.py → pre_commit/languages/unsupported.py b/pre_commit/languages/system.py → pre_commit/languages/unsupported.py
diff --git a/pre_commit/languages/script.py → pre_commit/languages/unsupported_script.py b/pre_commit/languages/script.py → pre_commit/languages/unsupported_script.py
diff --git a/tests/clientlib_test.py b/tests/clientlib_test.py
@@ -380,6 +380,26 @@ def test_no_warning_for_non_deprecated_default_stages(caplog):
     assert caplog.record_tuples == []
 
 
+def test_unsupported_language_migration():
+    cfg = {'repos': [sample_local_config(), sample_local_config()]}
+    cfg['repos'][0]['hooks'][0]['language'] = 'system'
+    cfg['repos'][1]['hooks'][0]['language'] = 'script'
+
+    cfgv.validate(cfg, CONFIG_SCHEMA)
+    ret = cfgv.apply_defaults(cfg, CONFIG_SCHEMA)
+
+    assert ret['repos'][0]['hooks'][0]['language'] == 'unsupported'
+    assert ret['repos'][1]['hooks'][0]['language'] == 'unsupported_script'
+
+
+def test_unsupported_language_migration_language_required():
+    cfg = {'repos': [sample_local_config()]}
+    del cfg['repos'][0]['hooks'][0]['language']
+
+    with pytest.raises(cfgv.ValidationError):
+        cfgv.validate(cfg, CONFIG_SCHEMA)
+
+
 @pytest.mark.parametrize(
     'manifest_obj',
     (

diff --git a/tests/languages/system_test.py b/tests/languages/system_test.py
diff --git a/tests/languages/script_test.py → tests/languages/unsupported_script_test.py b/tests/languages/script_test.py → tests/languages/unsupported_script_test.py
@@ -1,14 +1,14 @@
 from __future__ import annotations
 
-from pre_commit.languages import script
+from pre_commit.languages import unsupported_script
 from pre_commit.util import make_executable
 from testing.language_helpers import run_language
 
 
-def test_script_language(tmp_path):
+def test_unsupported_script_language(tmp_path):
     exe = tmp_path.joinpath('main')
     exe.write_text('#!/usr/bin/env bash\necho hello hello world\n')
     make_executable(exe)
 
     expected = (0, b'hello hello world\n')
-    assert run_language(tmp_path, script, 'main') == expected
+    assert run_language(tmp_path, unsupported_script, 'main') == expected
diff --git a/tests/languages/unsupported_test.py b/tests/languages/unsupported_test.py
@@ -0,0 +1,10 @@
+from __future__ import annotations
+
+from pre_commit.languages import unsupported
+from testing.language_helpers import run_language
+
+
+def test_unsupported_language(tmp_path):
+    expected = (0, b'hello hello world\n')
+    ret = run_language(tmp_path, unsupported, 'echo hello hello world')
+    assert ret == expected
diff --git a/tests/repository_test.py b/tests/repository_test.py
@@ -17,7 +17,7 @@
 from pre_commit.clientlib import load_manifest
 from pre_commit.hook import Hook
 from pre_commit.languages import python
-from pre_commit.languages import system
+from pre_commit.languages import unsupported
 from pre_commit.prefix import Prefix
 from pre_commit.repository import _hook_installed
 from pre_commit.repository import all_hooks
@@ -424,7 +424,7 @@ def test_manifest_hooks(tempdir_factory, store):
         exclude_types=[],
         files='',
         id='bash_hook',
-        language='script',
+        language='unsupported_script',
         language_version='default',
         log_file='',
         minimum_pre_commit_version='0',
@@ -457,7 +457,7 @@ def test_non_installable_hook_error_for_language_version(store, caplog):
         'hooks': [{
             'id': 'system-hook',
             'name': 'system-hook',
-            'language': 'system',
+            'language': 'unsupported',
             'entry': 'python3 -c "import sys; print(sys.version)"',
             'language_version': 'python3.10',
         }],
@@ -469,7 +469,7 @@ def test_non_installable_hook_error_for_language_version(store, caplog):
     msg, = caplog.messages
     assert msg == (
         'The hook `system-hook` specifies `language_version` but is using '
-        'language `system` which does not install an environment.  '
+        'language `unsupported` which does not install an environment.  '
         'Perhaps you meant to use a specific language?'
     )
 
@@ -480,7 +480,7 @@ def test_non_installable_hook_error_for_additional_dependencies(store, caplog):
         'hooks': [{
             'id': 'system-hook',
             'name': 'system-hook',
-            'language': 'system',
+            'language': 'unsupported',
             'entry': 'python3 -c "import sys; print(sys.version)"',
             'additional_dependencies': ['astpretty'],
         }],
@@ -492,14 +492,14 @@ def test_non_installable_hook_error_for_additional_dependencies(store, caplog):
     msg, = caplog.messages
     assert msg == (
         'The hook `system-hook` specifies `additional_dependencies` but is '
-        'using language `system` which does not install an environment.  '
+        'using language `unsupported` which does not install an environment.  '
         'Perhaps you meant to use a specific language?'
     )
 
 
 def test_args_with_spaces_and_quotes(tmp_path):
     ret = run_language(
-        tmp_path, system,
+        tmp_path, unsupported,
         f"{shlex.quote(sys.executable)} -c 'import sys; print(sys.argv[1:])'",
         ('i have spaces', 'and"\'quotes', '$and !this'),
     )