add a function to return link

library_generation/test/utils/commit_message_formatter_unit_tests.py

@@ -14,7 +14,10 @@
 import unittest
 from unittest.mock import patch
 
-from library_generation.utils.commit_message_formatter import format_commit_message
+from library_generation.utils.commit_message_formatter import (
+    format_commit_message,
+    commit_link,
+)
 from library_generation.utils.commit_message_formatter import wrap_nested_commit
 from library_generation.utils.commit_message_formatter import wrap_override_commit
 
@@ -141,3 +144,12 @@ def test_wrap_override_commit_success(self):
             ],
             wrap_override_commit(messages),
         )
+
+    def test_commit_link_success(self):
+        with patch("git.Commit") as mock_commit:
+            commit = mock_commit.return_value
+            commit.hexsha = "1234567abcdefg"
+            self.assertEqual(
+                "[googleapis/googleapis@1234567](https://github.com/googleapis/googleapis/commit/1234567abcdefg)",
+                commit_link(commit),
+            )

library_generation/utils/commit_message_formatter.py

@@ -59,12 +59,9 @@ def wrap_nested_commit(commit: Commit, messages: List[str]) -> List[str]:
     :param messages: a (multi-line) commit message, one line per item.
     :return: wrapped messages.
     """
-    short_sha = commit.hexsha[:7]
     result = ["BEGIN_NESTED_COMMIT"]
     result.extend(messages)
-    result.append(
-        f"Source Link: [googleapis/googleapis@{short_sha}](https://github.com/googleapis/googleapis/commit/{commit.hexsha})"
-    )
+    result.append(f"Source Link: {commit_link(commit)}")
     result.append("END_NESTED_COMMIT")
     return result
 
@@ -80,3 +77,14 @@ def wrap_override_commit(messages: List[str]) -> List[str]:
     result.extend(messages)
     result.append("END_COMMIT_OVERRIDE")
     return result
+
+
+def commit_link(commit: Commit) -> str:
+    """
+    Create a link to the commit in Markdown format.
+
+    :param commit: a GitHub commit.
+    :return: a link in Markdown format.
+    """
+    short_sha = commit.hexsha[:7]
+    return f"[googleapis/googleapis@{short_sha}](https://github.com/googleapis/googleapis/commit/{commit.hexsha})"