Merge pull request #1388 from pre-commit/node_default_system

Default to `language_version: system` if node and npm are installed

tests/languages/node_test.py

@@ -0,0 +1,47 @@
+import sys
+from unittest import mock
+
+import pytest
+
+import pre_commit.constants as C
+from pre_commit import parse_shebang
+from pre_commit.languages.node import get_default_version
+
+
+ACTUAL_GET_DEFAULT_VERSION = get_default_version.__wrapped__
+
+
+@pytest.fixture
+def is_linux():
+    with mock.patch.object(sys, 'platform', 'linux'):
+        yield
+
+
+@pytest.fixture
+def is_win32():
+    with mock.patch.object(sys, 'platform', 'win32'):
+        yield
+
+
+@pytest.fixture
+def find_exe_mck():
+    with mock.patch.object(parse_shebang, 'find_executable') as mck:
+        yield mck
+
+
+@pytest.mark.usefixtures('is_linux')
+def test_sets_system_when_node_and_npm_are_available(find_exe_mck):
+    find_exe_mck.return_value = '/path/to/exe'
+    assert ACTUAL_GET_DEFAULT_VERSION() == 'system'
+
+
+@pytest.mark.usefixtures('is_linux')
+def test_uses_default_when_node_and_npm_are_not_available(find_exe_mck):
+    find_exe_mck.return_value = None
+    assert ACTUAL_GET_DEFAULT_VERSION() == C.DEFAULT
+
+
+@pytest.mark.usefixtures('is_win32')
+def test_sets_default_on_windows(find_exe_mck):
+    find_exe_mck.return_value = '/path/to/exe'
+    assert ACTUAL_GET_DEFAULT_VERSION() == C.DEFAULT

tests/repository_test.py

@@ -131,9 +131,9 @@ def test_python_hook(tempdir_factory, store):
 def test_python_hook_default_version(tempdir_factory, store):
     # make sure that this continues to work for platforms where default
     # language detection does not work
-    with mock.patch.object(
-            python, 'get_default_version', return_value=C.DEFAULT,
-    ):
+    returns_default = mock.Mock(return_value=C.DEFAULT)
+    lang = languages['python']._replace(get_default_version=returns_default)
+    with mock.patch.dict(languages, python=lang):
         test_python_hook(tempdir_factory, store)
 
 
@@ -243,6 +243,15 @@ def test_run_a_node_hook(tempdir_factory, store):
     )
 
 
+def test_run_a_node_hook_default_version(tempdir_factory, store):
+    # make sure that this continues to work for platforms where node is not
+    # installed at the system
+    returns_default = mock.Mock(return_value=C.DEFAULT)
+    lang = languages['node']._replace(get_default_version=returns_default)
+    with mock.patch.dict(languages, node=lang):
+        test_run_a_node_hook(tempdir_factory, store)
+
+
 def test_run_versioned_node_hook(tempdir_factory, store):
     _test_hook_repo(
         tempdir_factory, store, 'node_versioned_hooks_repo',