feat: introduce "strict" mode (#61)

conventional_pre_commit/format.py

@@ -14,6 +14,11 @@
     "style",
     "test",
 ]
+AUTOSQUASH_PREFIXES = [
+    "amend",
+    "fixup",
+    "squash",
+]
 
 
 def r_types(types):
@@ -39,6 +44,11 @@ def r_subject():
     return r" .+"
 
 
+def r_autosquash_prefixes():
+    """Regex str for autosquash prefixes."""
+    return "|".join(AUTOSQUASH_PREFIXES)
+
+
 def conventional_types(types=[]):
     """Return a list of Conventional Commits types merged with the given types."""
     if set(types) & set(CONVENTIONAL_TYPES) == set():
@@ -58,3 +68,17 @@ def is_conventional(input, types=DEFAULT_TYPES, optional_scope=True):
     regex = re.compile(pattern, re.DOTALL)
 
     return bool(regex.match(input))
+
+
+def has_autosquash_prefix(input):
+    """
+    Returns True if input starts with one of the autosquash prefixes used in git.
+    See the documentation, please https://git-scm.com/docs/git-rebase.
+
+    It doesn't check whether the rest of the input matches Conventional Commits
+    formatting.
+    """
+    pattern = f"^(({r_autosquash_prefixes()})! ).*$"
+    regex = re.compile(pattern, re.DOTALL)
+
+    return bool(regex.match(input))

conventional_pre_commit/hook.py

@@ -23,6 +23,9 @@ def main(argv=[]):
     parser.add_argument(
         "--force-scope", action="store_false", default=True, dest="optional_scope", help="Force commit to have scope defined."
     )
+    parser.add_argument(
+        "--strict", action="store_true", help="Force commit to strictly follow Conventional Commits formatting."
+    )
 
     if len(argv) < 1:
         argv = sys.argv[1:]
@@ -47,6 +50,10 @@ def main(argv=[]):
         )
         return RESULT_FAIL
 
+    if not args.strict:
+        if format.has_autosquash_prefix(message):
+            return RESULT_SUCCESS
+
     if format.is_conventional(message, args.types, args.optional_scope):
         return RESULT_SUCCESS
     else:

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "conventional_pre_commit"
-version = "2.3.0"
+version = "2.4.0"
 description = "A pre-commit hook that checks commit messages for Conventional Commits formatting."
 readme = "README.md"
 license = { file = "LICENSE" }

tests/conftest.py

@@ -37,3 +37,8 @@ def conventional_utf8_commit_path():
 @pytest.fixture
 def conventional_gbk_commit_path():
     return get_message_path("conventional_commit_gbk")
+
+
+@pytest.fixture
+def fixup_commit_path():
+    return get_message_path("fixup_commit")

tests/messages/fixup_commit

@@ -0,0 +1 @@
+fixup! feature: implement something cool

tests/test_format.py

@@ -102,6 +102,14 @@ def test_r_subject__special_chars():
     assert regex.match(" some thing")
 
 
+def test_r_autosquash_prefixes():
+    result = format.r_autosquash_prefixes()
+    regex = re.compile(result)
+
+    for prefix in format.AUTOSQUASH_PREFIXES:
+        assert regex.match(prefix)
+
+
 def test_conventional_types__default():
     result = format.conventional_types()
 
@@ -210,3 +218,20 @@ def test_is_conventional__missing_delimiter():
     input = "feat message"
 
     assert not format.is_conventional(input)
+
+
+@pytest.mark.parametrize(
+    "input,has_prefix",
+    [
+        ("amend! ", True),
+        ("fixup! ", True),
+        ("squash! ", True),
+        ("squash! whatever .. $12 #", True),
+        ("squash!", False),
+        (" squash! ", False),
+        ("squash!:", False),
+        ("feat(foo):", False),
+    ],
+)
+def test_has_autosquash_prefix(input, has_prefix):
+    assert format.has_autosquash_prefix(input) == has_prefix

tests/test_hook.py

@@ -104,3 +104,15 @@ def test_main_success__conventional_with_scope(cmd, conventional_commit_with_sco
     result = subprocess.call((cmd, "--force-scope", conventional_commit_with_scope_path))
 
     assert result == RESULT_SUCCESS
+
+
+def test_main_success__fixup_commit(cmd, fixup_commit_path):
+    result = subprocess.call((cmd, fixup_commit_path))
+
+    assert result == RESULT_SUCCESS
+
+
+def test_main_success__fail_commit(cmd, fixup_commit_path):
+    result = subprocess.call((cmd, "--strict", fixup_commit_path))
+
+    assert result == RESULT_FAIL