Don't warn about subject line length for the fixup commits

The fixup commits' subject line has a prefix which has its own
length, so warning about the exceeding length is not accurate.
Given that the fixup commits can not be merged, because they
cause a danger failure, it's safe to ignore the length check
for them.

diff --git a/dangerfile.py b/dangerfile.py
index 41cecb079a23e99144f816a1ecddd93f93015e9c..cc1f40667212ce8ca24374a3256989fbd9446527 100644 (file)
--- a/dangerfile.py
+++ b/dangerfile.py
@@ -99,11 +99,13 @@ fixup_error_logged = False
 for commit in danger.git.commits:
     message_lines = commit.message.splitlines()
     subject = message_lines[0]
-    if not fixup_error_logged and (
+    is_merge = subject.startswith("Merge branch ")
+    is_fixup = (
         subject.startswith("fixup!")
         or subject.startswith("amend!")
         or subject.startswith("Apply suggestion")
-    ):
+    )
+    if not fixup_error_logged and is_fixup:
         fail(
             "Fixup commits are still present in this merge request. "
             "Please squash them before merging."
@@ -115,7 +117,7 @@ for commit in danger.git.commits:
             f"Prohibited keyword `{match.groups()[0]}` detected "
             f"at the start of a subject line in commit {commit.sha}."
         )
-    if len(subject) > 72 and not subject.startswith("Merge branch "):
+    if len(subject) > 72 and not is_merge and not is_fixup:
         warn(
             f"Subject line for commit {commit.sha} is too long: "
             f"```{subject}``` ({len(subject)} > 72 characters)."