Repository: cli/cli
File: pkg/cmd/release/shared/fetch_test.go (Go)

Code before:
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			fakeHTTP := &httpmock.Registry{}
			defer fakeHTTP.Verify(t)

			repo, err := ghrepo.FromFullName("owner/repo")
			require.NoError(t, err)

			path := "repos/owner/repo/git/ref/tags/" + tt.tagName
			if tt.responseStatus == 404 {
				fakeHTTP.Register(httpmock.REST("GET", path), httpmock.StatusStringResponse(404, "Not Found"))
			} else {
				fakeHTTP.Register(httpmock.REST("GET", path), httpmock.StringResponse(tt.responseBody))
			}

			httpClient := &http.Client{Transport: fakeHTTP}
			ctx := context.Background()

			sha, err := FetchRefSHA(ctx, httpClient, repo, tt.tagName)

			if tt.errorMessage != "" {
				require.Error(t, err)
				assert.EqualError(t, err, tt.errorMessage)
			} else {
				require.NoError(t, err)
				assert.Equal(t, tt.expectedSHA, sha)
			}
		})
	}
}


Review comment (suggestion):
Two points:
- Only the `assert.EqualError` is enough (it also checks the error is not `nil`).
- We need to assert `sha` is an empty string.

```suggestion
				require.EqualError(t, err, tt.errorMessage)
				assert.Empty(t, sha)
```

Code after:
package shared

import (
	"context"
	"net/http"
	"testing"

	"github.com/cli/go-gh/v2/pkg/api"

	"github.com/cli/cli/v2/internal/ghrepo"
	"github.com/cli/cli/v2/pkg/httpmock"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestFetchRefSHA(t *testing.T) {
	tests := []struct {
		name            string
		tagName         string
		responseStatus  int
		responseBody    string
		responseMessage string
		expectedSHA     string
		errorMessage    string
	}{
		{
			name:           "match (200)",
			tagName:        "v1.2.3",
			responseStatus: 200,
			responseBody:   `{"object": {"sha": "1234567890abcdef1234567890abcdef12345678"}}`,
			expectedSHA:    "1234567890abcdef1234567890abcdef12345678",
		},
		{
			name:            "non-match (404)",
			tagName:         "v1.2.3",
			responseStatus:  404,
			responseMessage: `Not found`,
			errorMessage:    "release not found",
		},
		{
			name:            "server error (500)",
			tagName:         "v1.2.3",
			responseStatus:  500,
			responseMessage: `arbitrary error"`,
			errorMessage:    "HTTP 500: arbitrary error\" (https://api.github.com/repos/owner/repo/git/ref/tags/v1.2.3)",
		},
		{
			name:           "malformed JSON with 200",
			tagName:        "v1.2.3",
			responseStatus: 200,
			responseBody:   `{"object": {"sha":`,
			errorMessage:   "failed to parse ref response: unexpected EOF",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			fakeHTTP := &httpmock.Registry{}
			defer fakeHTTP.Verify(t)

			repo, err := ghrepo.FromFullName("owner/repo")
			require.NoError(t, err)

			path := "repos/owner/repo/git/ref/tags/" + tt.tagName
			if tt.responseStatus == 404 || tt.responseStatus == 500 {
				fakeHTTP.Register(
					httpmock.REST("GET", path),
					httpmock.JSONErrorResponse(tt.responseStatus, api.HTTPError{
						StatusCode: tt.responseStatus,
						Message:    tt.responseMessage,
					}),
				)
			} else {
				fakeHTTP.Register(
					httpmock.REST("GET", path),
					httpmock.StatusStringResponse(tt.responseStatus, tt.responseBody),
				)
			}

			httpClient := &http.Client{Transport: fakeHTTP}
			ctx := context.Background()

			sha, err := FetchRefSHA(ctx, httpClient, repo, tt.tagName)

			if tt.errorMessage != "" {
				assert.Contains(t, err.Error(), tt.errorMessage)
				assert.Empty(t, sha)
			} else {
				require.NoError(t, err)
				assert.Equal(t, tt.expectedSHA, sha)
			}
		})
	}
}