Merge pull request #1155 from metalogical/FIX-detached-head

fix regression in support for detached HEAD state

command/pr.go

@@ -131,7 +131,7 @@ func prStatus(cmd *cobra.Command, args []string) error {
 	repoOverride, _ := cmd.Flags().GetString("repo")
 	currentPRNumber, currentPRHeadRef, err := prSelectorForCurrentBranch(ctx, baseRepo)
 
-	if err != nil && repoOverride == "" && err.Error() != "git: not on any branch" {
+	if err != nil && repoOverride == "" && !errors.Is(err, git.ErrNotOnAnyBranch) {
 		return fmt.Errorf("could not query for pull request for current branch: %w", err)
 	}
 

command/pr_test.go

@@ -299,6 +299,38 @@ Requesting a code review from you
 	}
 }
 
+func TestPRStatus_detachedHead(t *testing.T) {
+	initBlankContext("", "OWNER/REPO", "")
+	http := initFakeHTTP()
+	http.StubRepoResponse("OWNER", "REPO")
+
+	http.StubResponse(200, bytes.NewBufferString(`
+	{ "data": {} }
+	`))
+
+	output, err := RunCommand("pr status")
+	if err != nil {
+		t.Errorf("error running command `pr status`: %v", err)
+	}
+
+	expected := `
+Relevant pull requests in OWNER/REPO
+
+Current branch
+  There is no current branch
+
+Created by you
+  You have no open pull requests
+
+Requesting a code review from you
+  You have no pull requests to review
+
+`
+	if output.String() != expected {
+		t.Errorf("expected %q, got %q", expected, output.String())
+	}
+}
+
 func TestPRList(t *testing.T) {
 	initBlankContext("", "OWNER/REPO", "master")
 	http := initFakeHTTP()

context/blank_context.go

@@ -40,7 +40,7 @@ func (c *blankContext) SetAuthToken(t string) {
 
 func (c *blankContext) Branch() (string, error) {
 	if c.branch == "" {
-		return "", fmt.Errorf("branch was not initialized")
+		return "", fmt.Errorf("branch was not initialized: %w", git.ErrNotOnAnyBranch)
 	}
 	return c.branch, nil
 }

git/git.go

@@ -13,6 +13,9 @@ import (
 	"github.com/cli/cli/internal/run"
 )
 
+// ErrNotOnAnyBranch indicates that the users is in detached HEAD state
+var ErrNotOnAnyBranch = errors.New("git: not on any branch")
+
 // Ref represents a git commit reference
 type Ref struct {
 	Hash string
@@ -64,7 +67,7 @@ func CurrentBranch() (string, error) {
 	if errors.As(err, &cmdErr) {
 		if cmdErr.Stderr.Len() == 0 {
 			// Detached head
-			return "", errors.New("git: not on any branch")
+			return "", ErrNotOnAnyBranch
 		}
 	}
 

git/git_test.go

@@ -67,9 +67,8 @@ func Test_CurrentBranch_detached_head(t *testing.T) {
 	if err == nil {
 		t.Errorf("expected an error")
 	}
-	expectedError := "git: not on any branch"
-	if err.Error() != expectedError {
-		t.Errorf("got unexpected error: %s instead of %s", err.Error(), expectedError)
+	if err != ErrNotOnAnyBranch {
+		t.Errorf("got unexpected error: %s instead of %s", err, ErrNotOnAnyBranch)
 	}
 	if len(cs.Calls) != 1 {
 		t.Errorf("expected 1 git call, saw %d", len(cs.Calls))