fix(gitea): preserve source_url on retest comment reruns

Populate PR source/target fields for Forgejo/Gitea comment payloads
(issue_comment and pull_request_comment) so comment-triggered reruns
preserve the same source_url semantics as pull_request events.

This updates the runtime Gitea parser and keeps the tkn pac CEL parser
in sync, then adds regression coverage for provider parsing, CEL
parsing, and a Gitea e2e test that validates source_url on the second
rerun PipelineRun created from a targeted /retest.

Fixes #2496

Jira: https://issues.redhat.com/browse/SRVKP-10575
Signed-off-by: Chmouel Boudjnah <chmouel@redhat.com>

Author: chmouel

pkg/cmd/tknpac/cel/parser.go

@@ -558,6 +558,30 @@ func (p *BitbucketDataCenterParser) PopulateEvent(event *info.Event, parsedEvent
 
 type GiteaParser struct{}
 
+func populateGiteaPullRequestFields(event *info.Event, pr *forgejostructs.PullRequest) {
+	if pr == nil {
+		return
+	}
+
+	event.PullRequestTitle = pr.Title
+	if pr.Head != nil {
+		event.SHA = pr.Head.Sha
+		if pr.HTMLURL != "" && pr.Head.Sha != "" {
+			event.SHAURL = fmt.Sprintf("%s/commit/%s", pr.HTMLURL, pr.Head.Sha)
+		}
+		event.HeadBranch = pr.Head.Ref
+		if pr.Head.Repository != nil {
+			event.HeadURL = pr.Head.Repository.HTMLURL
+		}
+	}
+	if pr.Base != nil {
+		event.BaseBranch = pr.Base.Ref
+		if pr.Base.Repository != nil {
+			event.BaseURL = pr.Base.Repository.HTMLURL
+		}
+	}
+}
+
 func (p *GiteaParser) GetEventTypeHeader() string {
 	return "X-Gitea-Event-Type"
 }
@@ -598,24 +622,8 @@ func (p *GiteaParser) PopulateEvent(event *info.Event, parsedEvent any) error {
 			event.Sender = gitEvent.Sender.UserName
 		}
 		if gitEvent.PullRequest != nil {
-			if gitEvent.PullRequest.Head != nil {
-				event.SHA = gitEvent.PullRequest.Head.Sha
-				if gitEvent.PullRequest.HTMLURL != "" && gitEvent.PullRequest.Head.Sha != "" {
-					event.SHAURL = fmt.Sprintf("%s/commit/%s", gitEvent.PullRequest.HTMLURL, gitEvent.PullRequest.Head.Sha)
-				}
-				event.HeadBranch = gitEvent.PullRequest.Head.Ref
-				if gitEvent.PullRequest.Head.Repository != nil {
-					event.HeadURL = gitEvent.PullRequest.Head.Repository.HTMLURL
-				}
-			}
-			if gitEvent.PullRequest.Base != nil {
-				event.BaseBranch = gitEvent.PullRequest.Base.Ref
-				if gitEvent.PullRequest.Base.Repository != nil {
-					event.BaseURL = gitEvent.PullRequest.Base.Repository.HTMLURL
-				}
-			}
+			populateGiteaPullRequestFields(event, gitEvent.PullRequest)
 			event.PullRequestNumber = int(gitEvent.Index)
-			event.PullRequestTitle = gitEvent.PullRequest.Title
 			for _, label := range gitEvent.PullRequest.Labels {
 				if label != nil {
 					event.PullRequestLabel = append(event.PullRequestLabel, label.Name)
@@ -674,6 +682,10 @@ func (p *GiteaParser) PopulateEvent(event *info.Event, parsedEvent any) error {
 			event.TriggerComment = gitEvent.Comment.Body
 		}
 		event.PullRequestNumber = extractPullRequestNumber(issue.URL)
+		populateGiteaPullRequestFields(event, gitEvent.PullRequest)
+		if event.PullRequestNumber == 0 && gitEvent.PullRequest != nil {
+			event.PullRequestNumber = int(gitEvent.PullRequest.Index)
+		}
 	default:
 		return fmt.Errorf("unsupported Gitea event type: %T", gitEvent)
 	}

pkg/cmd/tknpac/cel/parser_test.go

@@ -391,6 +391,87 @@ func TestGiteaParserWithMissingFields(t *testing.T) {
 				assert.Equal(t, event.TriggerComment, "")
 			},
 		},
+		{
+			name: "issue comment with pull request source repository",
+			payload: `{
+				"action": "created",
+				"issue": {
+					"url": "https://gitea.com/api/v1/repos/test-org/test-repo/issues/42",
+					"number": 42,
+					"pull_request": {"html_url": "https://gitea.com/test-org/test-repo/pulls/42"}
+				},
+				"pull_request": {
+					"number": 42,
+					"title": "Test PR",
+					"head": {
+						"ref": "feature",
+						"sha": "abc123",
+						"repo": {"html_url": "https://gitea.com/testuser/test-repo-fork"}
+					},
+					"base": {
+						"ref": "main",
+						"repo": {"html_url": "https://gitea.com/test-org/test-repo"}
+					},
+					"html_url": "https://gitea.com/test-org/test-repo/pulls/42"
+				},
+				"comment": {"body": "/retest"},
+				"repository": {
+					"name": "test-repo",
+					"owner": {"login": "test-org"},
+					"html_url": "https://gitea.com/test-org/test-repo",
+					"default_branch": "main"
+				},
+				"sender": {"login": "testuser"}
+			}`,
+			wantErr: false,
+			checks: func(t *testing.T, event *info.Event) {
+				assert.Equal(t, event.PullRequestNumber, 42)
+				assert.Equal(t, event.HeadURL, "https://gitea.com/testuser/test-repo-fork")
+				assert.Equal(t, event.BaseURL, "https://gitea.com/test-org/test-repo")
+				assert.Equal(t, event.HeadBranch, "feature")
+				assert.Equal(t, event.BaseBranch, "main")
+				assert.Equal(t, event.SHA, "abc123")
+				assert.Equal(t, event.SHAURL, "https://gitea.com/test-org/test-repo/pulls/42/commit/abc123")
+			},
+		},
+		{
+			name: "pull request comment with pull request source repository",
+			payload: `{
+				"action": "created",
+				"issue": {
+					"url": "https://gitea.com/api/v1/repos/test-org/test-repo/issues/43",
+					"number": 43,
+					"pull_request": {"html_url": "https://gitea.com/test-org/test-repo/pulls/43"}
+				},
+				"pull_request": {
+					"number": 43,
+					"title": "Another PR",
+					"head": {
+						"ref": "bugfix",
+						"sha": "def456",
+						"repo": {"html_url": "https://gitea.com/testuser/test-repo-fork"}
+					},
+					"base": {
+						"ref": "main",
+						"repo": {"html_url": "https://gitea.com/test-org/test-repo"}
+					},
+					"html_url": "https://gitea.com/test-org/test-repo/pulls/43"
+				},
+				"comment": {"body": "/test"},
+				"repository": {
+					"name": "test-repo",
+					"owner": {"login": "test-org"}
+				},
+				"sender": {"login": "testuser"}
+			}`,
+			wantErr: false,
+			checks: func(t *testing.T, event *info.Event) {
+				assert.Equal(t, event.PullRequestNumber, 43)
+				assert.Equal(t, event.HeadURL, "https://gitea.com/testuser/test-repo-fork")
+				assert.Equal(t, event.BaseURL, "https://gitea.com/test-org/test-repo")
+				assert.Equal(t, event.SHA, "def456")
+			},
+		},
 		{
 			name: "pull request with missing head repository",
 			payload: `{
@@ -429,6 +510,8 @@ func TestGiteaParserWithMissingFields(t *testing.T) {
 			switch {
 			case strings.Contains(tt.name, "push"):
 				headers["X-Gitea-Event-Type"] = "push"
+			case strings.Contains(tt.name, "pull request comment"):
+				headers["X-Gitea-Event-Type"] = "pull_request_comment"
 			case strings.Contains(tt.name, "issue comment"):
 				headers["X-Gitea-Event-Type"] = "issue_comment"
 			}

pkg/provider/gitea/gitea.go

@@ -475,6 +475,12 @@ func (v *Provider) GetCommitInfo(_ context.Context, runevent *info.Event) error
 		runevent.SHA = pr.Head.Sha
 		runevent.HeadBranch = pr.Head.Ref
 		runevent.BaseBranch = pr.Base.Ref
+		if runevent.HeadURL == "" && pr.Head.Repository != nil {
+			runevent.HeadURL = pr.Head.Repository.HTMLURL
+		}
+		if runevent.BaseURL == "" && pr.Base.Repository != nil {
+			runevent.BaseURL = pr.Base.Repository.HTMLURL
+		}
 		sha = pr.Head.Sha
 	}
 	commit, _, err := v.Client().GetSingleCommit(runevent.Organization, runevent.Repository, sha)

pkg/provider/gitea/gitea_test.go

@@ -1112,3 +1112,55 @@ func TestGetCommitInfo(t *testing.T) {
 		})
 	}
 }
+
+func TestGetCommitInfoPRLookupPopulatesURLs(t *testing.T) {
+	ctx, _ := rtesting.SetupFakeContext(t)
+	client, mux, tearDown := tgitea.Setup(t)
+	defer tearDown()
+
+	event := &info.Event{
+		Organization:      "owner",
+		Repository:        "repo",
+		PullRequestNumber: 42,
+		// SHA intentionally empty to trigger PR lookup path
+	}
+
+	// Mock GetPullRequest endpoint
+	mux.HandleFunc("/repos/owner/repo/pulls/42", func(rw http.ResponseWriter, _ *http.Request) {
+		fmt.Fprint(rw, `{
+			"head": {
+				"ref": "feature-branch",
+				"sha": "abc123",
+				"repo": {
+					"html_url": "https://gitea.com/fork-owner/repo"
+				}
+			},
+			"base": {
+				"ref": "main",
+				"repo": {
+					"html_url": "https://gitea.com/owner/repo"
+				}
+			}
+		}`)
+	})
+
+	// Mock GetSingleCommit endpoint
+	mux.HandleFunc("/repos/owner/repo/git/commits/abc123", func(rw http.ResponseWriter, _ *http.Request) {
+		fmt.Fprint(rw, `{
+			"sha": "abc123",
+			"html_url": "https://gitea.com/owner/repo/commit/abc123",
+			"commit": {
+				"message": "feat: test commit"
+			}
+		}`)
+	})
+
+	provider := &Provider{giteaClient: client}
+	err := provider.GetCommitInfo(ctx, event)
+	assert.NilError(t, err)
+	assert.Equal(t, "abc123", event.SHA)
+	assert.Equal(t, "feature-branch", event.HeadBranch)
+	assert.Equal(t, "main", event.BaseBranch)
+	assert.Equal(t, "https://gitea.com/fork-owner/repo", event.HeadURL, "HeadURL should be populated from PR lookup")
+	assert.Equal(t, "https://gitea.com/owner/repo", event.BaseURL, "BaseURL should be populated from PR lookup")
+}