fix: get_author() to traverse full backport chain

pretty_release_notes/models/pull_request.py

@@ -132,7 +132,10 @@ def set_reviewers(self) -> set[str]:
 		return self.reviewers
 
 	def get_author(self) -> str:
-		return self.backport_of.author if self.backport_of else self.author
+		if self.backport_of:
+			self.backport_of._set_backport_of()
+			return self.backport_of.get_author()
+		return self.author
 
 	def get_summary_key(self) -> str:
 		# Keep in mind that this needs to work before `self.backport_of` is initialised

tests/test_pull_request.py

@@ -1,3 +1,5 @@
+from unittest.mock import patch
+
 from pretty_release_notes.github_client import GitHubClient
 from pretty_release_notes.models.pull_request import PullRequest
 from pretty_release_notes.models.repository import Repository
@@ -62,3 +64,65 @@ def test_revert_with_backport():
 	assert pr.is_revert is True
 	assert pr.reverted_pr_number == "150"
 	assert pr.backport_no == "200"  # Should still detect backport
+
+
+def test_get_author_chained_backports():
+	"""Test that get_author() traverses the full backport chain.
+
+	Chain: PR4 (backport of PR3) -> PR3 (backport of PR2) -> PR2 (backport of PR1) -> PR1 (original)
+	get_author() on PR4 should return PR1's author, not PR3's or PR2's author.
+	"""
+	github = GitHubClient("test_token")
+	repo = Repository(
+		owner="frappe",
+		name="frappe",
+		url="https://api.github.com/repos/frappe/frappe",
+		html_url="https://github.com/frappe/frappe",
+	)
+
+	pr1 = PullRequest(
+		github=github,
+		repository=repo,
+		id=1,
+		title="feat: original feature",
+		body="",
+		html_url="https://example.com/1",
+		author="original_author",
+	)
+	pr2 = PullRequest(
+		github=github,
+		repository=repo,
+		id=2,
+		title="feat: original feature (backport #1)",
+		body="",
+		html_url="https://example.com/2",
+		author="mergify[bot]",
+		backport_of=pr1,
+	)
+	pr3 = PullRequest(
+		github=github,
+		repository=repo,
+		id=3,
+		title="feat: original feature (backport #2)",
+		body="",
+		html_url="https://example.com/3",
+		author="mergify[bot]",
+		backport_of=pr2,
+	)
+	pr4 = PullRequest(
+		github=github,
+		repository=repo,
+		id=4,
+		title="feat: original feature (backport #3)",
+		body="",
+		html_url="https://example.com/4",
+		author="mergify[bot]",
+		backport_of=pr3,
+	)
+
+	# Mock _set_backport_of to avoid GitHub API calls; backport_of is pre-set above
+	with patch.object(PullRequest, "_set_backport_of"):
+		assert pr1.get_author() == "original_author"
+		assert pr2.get_author() == "original_author"
+		assert pr3.get_author() == "original_author"
+		assert pr4.get_author() == "original_author"