New hook 'destroyed-symlinks' to detect symlinks which are changed to regular files with a content of a path which that symlink was pointing to; move zsplit to util
diff --git a/tests/destroyed_symlinks_test.py b/tests/destroyed_symlinks_test.py
new file mode 100644
index 0000000..d2c9031
--- /dev/null
+++ b/tests/destroyed_symlinks_test.py
@@ -0,0 +1,74 @@
+import os
+import subprocess
+
+import pytest
+
+from pre_commit_hooks.destroyed_symlinks import find_destroyed_symlinks
+from pre_commit_hooks.destroyed_symlinks import main
+
+TEST_SYMLINK = 'test_symlink'
+TEST_SYMLINK_TARGET = '/doesnt/really/matters'
+TEST_FILE = 'test_file'
+TEST_FILE_RENAMED = f'{TEST_FILE}_renamed'
+
+
+@pytest.fixture
+def repo_with_destroyed_symlink(tmpdir):
+ source_repo = tmpdir.join('src')
+ os.makedirs(source_repo, exist_ok=True)
+ test_repo = tmpdir.join('test')
+ with source_repo.as_cwd():
+ subprocess.check_call(('git', 'init'))
+ os.symlink(TEST_SYMLINK_TARGET, TEST_SYMLINK)
+ with open(TEST_FILE, 'w') as f:
+ print('some random content', file=f)
+ subprocess.check_call(('git', 'add', '.'))
+ subprocess.check_call(
+ ('git', 'commit', '--no-gpg-sign', '-m', 'initial'),
+ )
+ assert b'120000 ' in subprocess.check_output(
+ ('git', 'cat-file', '-p', 'HEAD^{tree}'),
+ )
+ subprocess.check_call(
+ ('git', '-c', 'core.symlinks=false', 'clone', source_repo, test_repo),
+ )
+ with test_repo.as_cwd():
+ subprocess.check_call(
+ ('git', 'config', '--local', 'core.symlinks', 'true'),
+ )
+ subprocess.check_call(('git', 'mv', TEST_FILE, TEST_FILE_RENAMED))
+ assert not os.path.islink(test_repo.join(TEST_SYMLINK))
+ yield test_repo
+
+
+def test_find_destroyed_symlinks(repo_with_destroyed_symlink):
+ with repo_with_destroyed_symlink.as_cwd():
+ assert find_destroyed_symlinks([]) == []
+ assert main([]) == 0
+
+ subprocess.check_call(('git', 'add', TEST_SYMLINK))
+ assert find_destroyed_symlinks([TEST_SYMLINK]) == [TEST_SYMLINK]
+ assert find_destroyed_symlinks([]) == []
+ assert main([]) == 0
+ assert find_destroyed_symlinks([TEST_FILE_RENAMED, TEST_FILE]) == []
+ ALL_STAGED = [TEST_SYMLINK, TEST_FILE_RENAMED]
+ assert find_destroyed_symlinks(ALL_STAGED) == [TEST_SYMLINK]
+ assert main(ALL_STAGED) != 0
+
+ with open(TEST_SYMLINK, 'a') as f:
+ print(file=f) # add trailing newline
+ subprocess.check_call(['git', 'add', TEST_SYMLINK])
+ assert find_destroyed_symlinks(ALL_STAGED) == [TEST_SYMLINK]
+ assert main(ALL_STAGED) != 0
+
+ with open(TEST_SYMLINK, 'w') as f:
+ print('0' * len(TEST_SYMLINK_TARGET), file=f)
+ subprocess.check_call(('git', 'add', TEST_SYMLINK))
+ assert find_destroyed_symlinks(ALL_STAGED) == []
+ assert main(ALL_STAGED) == 0
+
+ with open(TEST_SYMLINK, 'w') as f:
+ print('0' * (len(TEST_SYMLINK_TARGET) + 3), file=f)
+ subprocess.check_call(('git', 'add', TEST_SYMLINK))
+ assert find_destroyed_symlinks(ALL_STAGED) == []
+ assert main(ALL_STAGED) == 0
