Handle protection status errors for unprotected branches

github/repos.go

@@ -8,11 +8,16 @@ package github
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"strings"
 )
 
+const githubBranchNotProtected string = "Branch not protected"
+
+var ErrBranchNotProtected = errors.New("branch is not protected")
+
 // RepositoriesService handles communication with the repository related
 // methods of the GitHub API.
 //
@@ -1009,6 +1014,9 @@ func (s *RepositoriesService) GetBranchProtection(ctx context.Context, owner, re
 	p := new(Protection)
 	resp, err := s.client.Do(ctx, req, p)
 	if err != nil {
+		if isBranchNotProtected(err) {
+			err = ErrBranchNotProtected
+		}
 		return nil, resp, err
 	}
 
@@ -1028,6 +1036,9 @@ func (s *RepositoriesService) GetRequiredStatusChecks(ctx context.Context, owner
 	p := new(RequiredStatusChecks)
 	resp, err := s.client.Do(ctx, req, p)
 	if err != nil {
+		if isBranchNotProtected(err) {
+			err = ErrBranchNotProtected
+		}
 		return nil, resp, err
 	}
 
@@ -1046,6 +1057,9 @@ func (s *RepositoriesService) ListRequiredStatusChecksContexts(ctx context.Conte
 
 	resp, err = s.client.Do(ctx, req, &contexts)
 	if err != nil {
+		if isBranchNotProtected(err) {
+			err = ErrBranchNotProtected
+		}
 		return nil, resp, err
 	}
 
@@ -1539,3 +1553,12 @@ func (s *RepositoriesService) Dispatch(ctx context.Context, owner, repo string,
 
 	return r, resp, nil
 }
+
+// isBranchNotProtected determines whether a branch is not protected
+// based on the error message returned by GitHub API.
+func isBranchNotProtected(err error) bool {
+	if errorResponse, ok := err.(*ErrorResponse); ok {
+		return errorResponse.Message == githubBranchNotProtected
+	}
+	return false
+}

github/repos_test.go

@@ -1150,6 +1150,32 @@ func TestRepositoriesService_GetBranchProtection_noDismissalRestrictions(t *test
 	}
 }
 
+func TestRepositoriesService_GetBranchProtection_branchNotProtected(t *testing.T) {
+	client, mux, _, teardown := setup()
+	defer teardown()
+
+	mux.HandleFunc("/repos/o/r/branches/b/protection", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+
+		w.WriteHeader(http.StatusBadRequest)
+		fmt.Fprintf(w, `{
+			"message": "Branch not protected",
+			"documentation_url": "https://docs.github.com/rest/reference/repos#get-branch-protection"
+			}`)
+	})
+
+	ctx := context.Background()
+	protection, _, err := client.Repositories.GetBranchProtection(ctx, "o", "r", "b")
+
+	if protection != nil {
+		t.Errorf("Repositories.GetBranchProtection returned non-nil protection data")
+	}
+
+	if err != ErrBranchNotProtected {
+		t.Errorf("Repositories.GetBranchProtection returned an invalid error: %v", err)
+	}
+}
+
 func TestRepositoriesService_UpdateBranchProtection(t *testing.T) {
 	client, mux, _, teardown := setup()
 	defer teardown()
@@ -1387,6 +1413,32 @@ func TestRepositoriesService_GetRequiredStatusChecks(t *testing.T) {
 	})
 }
 
+func TestRepositoriesService_GetRequiredStatusChecks_branchNotProtected(t *testing.T) {
+	client, mux, _, teardown := setup()
+	defer teardown()
+
+	mux.HandleFunc("/repos/o/r/branches/b/protection/required_status_checks", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+
+		w.WriteHeader(http.StatusBadRequest)
+		fmt.Fprintf(w, `{
+			"message": "Branch not protected",
+			"documentation_url": "https://docs.github.com/rest/reference/repos#get-branch-protection"
+			}`)
+	})
+
+	ctx := context.Background()
+	checks, _, err := client.Repositories.GetRequiredStatusChecks(ctx, "o", "r", "b")
+
+	if checks != nil {
+		t.Errorf("Repositories.GetRequiredStatusChecks returned non-nil status-checks data")
+	}
+
+	if err != ErrBranchNotProtected {
+		t.Errorf("Repositories.GetRequiredStatusChecks returned an invalid error: %v", err)
+	}
+}
+
 func TestRepositoriesService_UpdateRequiredStatusChecks(t *testing.T) {
 	client, mux, _, teardown := setup()
 	defer teardown()
@@ -1502,6 +1554,32 @@ func TestRepositoriesService_ListRequiredStatusChecksContexts(t *testing.T) {
 	})
 }
 
+func TestRepositoriesService_ListRequiredStatusChecksContexts_branchNotProtected(t *testing.T) {
+	client, mux, _, teardown := setup()
+	defer teardown()
+
+	mux.HandleFunc("/repos/o/r/branches/b/protection/required_status_checks/contexts", func(w http.ResponseWriter, r *http.Request) {
+		testMethod(t, r, "GET")
+
+		w.WriteHeader(http.StatusBadRequest)
+		fmt.Fprintf(w, `{
+			"message": "Branch not protected",
+			"documentation_url": "https://docs.github.com/rest/reference/repos#get-branch-protection"
+			}`)
+	})
+
+	ctx := context.Background()
+	contexts, _, err := client.Repositories.ListRequiredStatusChecksContexts(ctx, "o", "r", "b")
+
+	if contexts != nil {
+		t.Errorf("Repositories.ListRequiredStatusChecksContexts returned non-nil contexts data")
+	}
+
+	if err != ErrBranchNotProtected {
+		t.Errorf("Repositories.ListRequiredStatusChecksContexts returned an invalid error: %v", err)
+	}
+}
+
 func TestRepositoriesService_GetPullRequestReviewEnforcement(t *testing.T) {
 	client, mux, _, teardown := setup()
 	defer teardown()