Merge pull request #653 from reviewdog/fork-detect

Fix detection logic to determin Pull Requests from forked repo

CHANGELOG.md

@@ -9,11 +9,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### :book: Release Note <!-- optional -->
 
 ### :rocket: Enhancements
-- [#563](https://github.com/reviewdog/reviewdog/issues/563) Use `CI_API_V4_URL` environment variable when present. 
+- [#563](https://github.com/reviewdog/reviewdog/issues/563) Use `CI_API_V4_URL` environment variable when present.
 - ...
 
 ### :bug: Fixes
 - [#609](https://github.com/reviewdog/reviewdog/issues/609) reviewdog command will fail with unexpected tool's error for github-check/github-pr-check reporters as well. ([@haya14busa])
+- [#603](https://github.com/reviewdog/reviewdog/issues/603) Fixed detection of Pull Requests from forked repo. ([@haya14busa])
 - ...
 
 ### :rotating_light: Breaking changes

cienv/github_actions.go

@@ -24,15 +24,22 @@ type GitHubEvent struct {
 	} `json:"head_commit"`
 }
 
+type GitHubRepo struct {
+	Owner struct {
+		ID int64 `json:"id"`
+	}
+}
+
 type GitHubPullRequest struct {
 	Number int `json:"number"`
 	Head   struct {
-		Sha  string `json:"sha"`
-		Ref  string `json:"ref"`
-		Repo struct {
-			Fork bool `json:"fork"`
-		} `json:"repo"`
+		Sha  string     `json:"sha"`
+		Ref  string     `json:"ref"`
+		Repo GitHubRepo `json:"repo"`
 	} `json:"head"`
+	Base struct {
+		Repo GitHubRepo `json:"repo"`
+	} `json:"base"`
 }
 
 // LoadGitHubEvent loads GitHubEvent if it's running in GitHub Actions.
@@ -94,3 +101,13 @@ func IsInGitHubAction() bool {
 	// https://help.github.com/en/articles/virtual-environments-for-github-actions#default-environment-variables
 	return os.Getenv("GITHUB_ACTION") != ""
 }
+
+// IsGitHubPRFromForkedRepo returns true if reviewdog is running in GitHub
+// Actions and running for PullRequests from forked repository.
+func IsGitHubPRFromForkedRepo() bool {
+	event, err := LoadGitHubEvent()
+	if err != nil {
+		return false
+	}
+	return event.PullRequest.Head.Repo.Owner.ID != event.PullRequest.Base.Repo.Owner.ID
+}

cmd/reviewdog/doghouse.go

@@ -193,11 +193,10 @@ func checkResultToAnnotation(c *reviewdog.CheckResult, wd, gitRelWd string) *dog
 // It returns true if reviewdog should exit with 1.
 // e.g. At least one annotation result is in diff.
 func reportResults(w io.Writer, filteredResultSet *reviewdog.FilteredResultMap) bool {
-	if filteredResultSet.Len() != 0 && isPRFromForkedRepo() {
+	if filteredResultSet.Len() != 0 && cienv.IsGitHubPRFromForkedRepo() {
 		fmt.Fprintln(w, `reviewdog: This is Pull-Request from forked repository.
 GitHub token doesn't have write permission of Check API, so reviewdog will
 report results via logging command [1].
-
 [1]: https://help.github.com/en/actions/automating-your-workflow-with-github-actions/development-tools-for-github-actions#logging-commands`)
 	}
 
@@ -252,11 +251,3 @@ report results via logging command [1].
 	}
 	return shouldFail
 }
-
-func isPRFromForkedRepo() bool {
-	event, err := cienv.LoadGitHubEvent()
-	if err != nil {
-		return false
-	}
-	return event.PullRequest.Head.Repo.Fork
-}

cmd/reviewdog/main.go

@@ -266,12 +266,11 @@ See -reporter flag for migration and set -reporter="github-pr-review" or -report
 		// instead of review comment because if it's PR from forked repository,
 		// GitHub token doesn't have write permission due to security concern and
 		// cannot post results via Review API.
-		if cienv.IsInGitHubAction() && isPRFromForkedRepo() {
+		if cienv.IsInGitHubAction() && cienv.IsGitHubPRFromForkedRepo() {
 			fmt.Fprintln(w, `reviewdog: This is Pull-Request from forked repository.
 GitHub token doesn't have write permission of Review API, so reviewdog will
 report results via logging command [1] and create annotations similar to
 github-pr-check reporter as a fallback.
-
 [1]: https://help.github.com/en/actions/automating-your-workflow-with-github-actions/development-tools-for-github-actions#logging-commands`)
 			cs = githubutils.NewGitHubActionLogWriter(opt.level)
 		} else {