Add pipenv language support to pre-commit

- Implement pipenv language module in pre-commit
- Update workflows to include pipenv language tests
- Add pipenv language to allowed languages in testing script
- Create comprehensive test suite for pipenv language support

pre_commit/languages/pipenv.py

@@ -0,0 +1,63 @@
+from __future__ import annotations
+
+import contextlib
+import os
+import sys
+from collections.abc import Generator
+from collections.abc import Sequence
+
+import pre_commit.constants as C
+from pre_commit import lang_base
+from pre_commit.envcontext import envcontext
+from pre_commit.languages import python
+from pre_commit.prefix import Prefix
+from pre_commit.util import cmd_output_b
+
+ENVIRONMENT_DIR = 'pipenv_env'
+get_default_version = python.get_default_version
+run_hook = python.run_hook
+
+def _assert_pipfile_exists(prefix: Prefix) -> None:
+    if not os.path.exists(os.path.join(prefix.prefix_dir, 'Pipfile')):
+        raise AssertionError(
+            '`language: pipenv` requires a Pipfile in the repository'
+        )
+
+def health_check(prefix: Prefix, version: str) -> str | None:
+    _assert_pipfile_exists(prefix)
+    directory = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
+    
+    try:
+        with in_env(prefix, version):
+            cmd_output_b('pipenv', 'check')
+        return None
+    except Exception as e:
+        return f'pipenv environment check failed: {e}'
+
+@contextlib.contextmanager
+def in_env(prefix: Prefix, version: str) -> Generator[None, None, None]:
+    directory = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
+    env = python.get_env_patch(directory)
+    with envcontext(env):
+        yield
+
+def install_environment(
+        prefix: Prefix,
+        version: str,
+        additional_dependencies: Sequence[str],
+) -> None:
+    _assert_pipfile_exists(prefix)
+    directory = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
+    
+    with in_env(prefix, version):
+        # Initialize virtualenv if it doesn't exist
+        if not os.path.exists(directory):
+            python_version = version if version != C.DEFAULT else f"{sys.version_info[0]}.{sys.version_info[1]}"
+            cmd_output_b('pipenv', '--python', python_version)
+        
+        # Install dependencies from Pipfile
+        cmd_output_b('pipenv', 'install', '--dev')
+        
+        # Install additional dependencies if specified
+        if additional_dependencies:
+            cmd_output_b('pipenv', 'install', *additional_dependencies)