fix(branch-prefix): recognize GitHub PR merge subject

docs/strategies/branch-prefix.md

@@ -25,15 +25,16 @@ to a new major version manually, or switch to
 
 The strategy only fires on commits whose subject contains the literal
 string `Merge branch` (the default `git merge` subject). Commits
-without that text return `none` regardless of prefix. This means:
+without one of those marks return `none` regardless of prefix. This
+means:
 
 - Standard `git merge feature/foo` → subject `Merge branch 'feature/foo' into main` → bump = minor ✓
-- GitHub's "Merge pull request #N from user/feature/foo" → does NOT
-  contain `Merge branch` → bump = none under defaults.
+- GitHub's `Merge pull request #N from user/feature/foo` → bump = minor ✓
 - Direct pushes to the default branch → bump = none.
 
-The `merge_mark_text` is configurable (defaults to `Merge branch`);
-adapt it for non-default merge-commit conventions.
+The `merge_mark_texts` tuple is configurable (defaults to
+`("Merge branch", "Merge pull request")`); adapt it for non-default
+merge-commit conventions (e.g. squash-merge prefixes).
 
 ## Customizing the prefixes
 
@@ -43,8 +44,8 @@ The strategy reads its prefixes from the application's settings layer:
   `("feature/",)`).
 - `patch` — tuple of prefixes that trigger a patch bump (default
   `("bugfix/", "hotfix/")`).
-- `merge_mark_text` — substring that marks a subject as a merge
-  commit (default `Merge branch`).
+- `merge_mark_texts` — tuple of substrings that mark a subject as a
+  merge commit (default `("Merge branch", "Merge pull request")`).
 
 These are set via the same pydantic-settings env-var mechanism used
 for tokens / endpoints — see the provider docs for the variable

semvertag/strategies/branch_prefix.py

@@ -15,7 +15,10 @@ class BranchPrefixConfig(pydantic.BaseModel):
 
     minor: tuple[_NonEmptyStr, ...] = pydantic.Field(default=("feature/",), min_length=1)
     patch: tuple[_NonEmptyStr, ...] = pydantic.Field(default=("bugfix/", "hotfix/"), min_length=1)
-    merge_mark_text: _NonEmptyStr = "Merge branch"
+    merge_mark_texts: tuple[_NonEmptyStr, ...] = pydantic.Field(
+        default=("Merge branch", "Merge pull request"),
+        min_length=1,
+    )
 
 
 @dataclasses.dataclass(frozen=True, slots=True, kw_only=True)
@@ -27,7 +30,7 @@ class BranchPrefixStrategy:
 
     def decide(self, commit: Commit) -> Bump:
         subject: typing.Final = subject_line(commit.message)
-        if self.config.merge_mark_text not in subject:
+        if not any(mark in subject for mark in self.config.merge_mark_texts):
             return Bump.NONE
         if any(prefix in subject for prefix in self.config.minor):
             return Bump.MINOR

tests/unit/test_branch_prefix_strategy.py

@@ -90,7 +90,7 @@ def test_honors_custom_minor_prefix_when_config_overrides_default() -> None:
         config=BranchPrefixConfig(
             minor=("feat/",),
             patch=("fix/",),
-            merge_mark_text="Auto-merge:",
+            merge_mark_texts=("Auto-merge:",),
         ),
     )
     assert custom.decide(_commit("Auto-merge: feat/new-thing")) is Bump.MINOR
@@ -99,10 +99,25 @@ def test_honors_custom_minor_prefix_when_config_overrides_default() -> None:
     assert custom.decide(_commit("Merge branch 'feat/x' into main")) is Bump.NONE
 
 
+def test_recognizes_github_pr_merge_subject_under_defaults() -> None:
+    default: typing.Final = BranchPrefixStrategy(config=BranchPrefixConfig())
+    assert default.decide(_commit("Merge pull request #42 from org/feature/new-thing")) is Bump.MINOR
+    assert default.decide(_commit("Merge pull request #43 from org/bugfix/bug-123")) is Bump.PATCH
+    assert default.decide(_commit("Merge pull request #44 from org/hotfix/urgent")) is Bump.PATCH
+    assert default.decide(_commit("Merge pull request #45 from org/chore/cleanup")) is Bump.NONE
+
+
+def test_recognizes_gitlab_merge_branch_subject_under_defaults() -> None:
+    default: typing.Final = BranchPrefixStrategy(config=BranchPrefixConfig())
+    assert default.decide(_commit("Merge branch 'feature/new-thing' into main")) is Bump.MINOR
+    assert default.decide(_commit("Merge branch 'bugfix/bug-123' into main")) is Bump.PATCH
+
+
 _INVALID_CONFIG_CASES: typing.Final = [
     {"minor": ()},
     {"patch": ()},
-    {"merge_mark_text": ""},
+    {"merge_mark_texts": ()},
+    {"merge_mark_texts": ("",)},
     {"minor": ("",)},
     {"patch": ("",)},
     {"minor": ("feature/", "")},