Add tests for JSON field support on issue and pr view commands

pkg/cmd/issue/view/view_test.go

@@ -16,11 +16,37 @@ import (
 	"github.com/cli/cli/v2/pkg/cmdutil"
 	"github.com/cli/cli/v2/pkg/httpmock"
 	"github.com/cli/cli/v2/pkg/iostreams"
+	"github.com/cli/cli/v2/pkg/jsonfieldstest"
 	"github.com/cli/cli/v2/test"
 	"github.com/google/shlex"
 	"github.com/stretchr/testify/assert"
 )
 
+func TestJSONFields(t *testing.T) {
+	jsonfieldstest.ExpectCommandToSupportJSONFields(t, NewCmdView, []string{
+		"assignees",
+		"author",
+		"body",
+		"closed",
+		"comments",
+		"createdAt",
+		"closedAt",
+		"id",
+		"labels",
+		"milestone",
+		"number",
+		"projectCards",
+		"projectItems",
+		"reactionGroups",
+		"state",
+		"title",
+		"updatedAt",
+		"url",
+		"isPinned",
+		"stateReason",
+	})
+}
+
 func runCommand(rt http.RoundTripper, isTTY bool, cli string) (*test.CmdOut, error) {
 	ios, _, stdout, stderr := iostreams.Test()
 	ios.SetStdoutTTY(isTTY)

pkg/cmd/pr/view/view_test.go

@@ -18,12 +18,61 @@ import (
 	"github.com/cli/cli/v2/pkg/cmdutil"
 	"github.com/cli/cli/v2/pkg/httpmock"
 	"github.com/cli/cli/v2/pkg/iostreams"
+	"github.com/cli/cli/v2/pkg/jsonfieldstest"
 	"github.com/cli/cli/v2/test"
 	"github.com/google/shlex"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
+func TestJSONFields(t *testing.T) {
+	jsonfieldstest.ExpectCommandToSupportJSONFields(t, NewCmdView, []string{
+		"additions",
+		"assignees",
+		"author",
+		"autoMergeRequest",
+		"baseRefName",
+		"body",
+		"changedFiles",
+		"closed",
+		"closedAt",
+		"comments",
+		"commits",
+		"createdAt",
+		"deletions",
+		"files",
+		"headRefName",
+		"headRefOid",
+		"headRepository",
+		"headRepositoryOwner",
+		"id",
+		"isCrossRepository",
+		"isDraft",
+		"labels",
+		"latestReviews",
+		"maintainerCanModify",
+		"mergeCommit",
+		"mergeStateStatus",
+		"mergeable",
+		"mergedAt",
+		"mergedBy",
+		"milestone",
+		"number",
+		"potentialMergeCommit",
+		"projectCards",
+		"projectItems",
+		"reactionGroups",
+		"reviewDecision",
+		"reviewRequests",
+		"reviews",
+		"state",
+		"statusCheckRollup",
+		"title",
+		"updatedAt",
+		"url",
+	})
+}
+
 func Test_NewCmdView(t *testing.T) {
 	tests := []struct {
 		name    string

pkg/jsonfieldstest/jsonfieldstest.go

@@ -0,0 +1,47 @@
+package jsonfieldstest
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/cli/cli/v2/pkg/cmdutil"
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func jsonFieldsFor(cmd *cobra.Command) []string {
+	// This annotation is added by the `cmdutil.AddJSONFlags` function.
+	//
+	// This is an extremely janky way to get access to this information but due to the fact we pass
+	// around concrete cobra.Command structs, there's no viable way to have typed access to the fields.
+	//
+	// It's also kind of fragile because it's several hops away from the code that actually validates the usage
+	// of these flags, so it's possible for things to get out of sync.
+	stringFields, ok := cmd.Annotations["help:json-fields"]
+	if !ok {
+		return nil
+	}
+
+	return strings.Split(stringFields, ",")
+}
+
+// NewCmdFunc represents the typical function signature we use for creating commands e.g. `NewCmdView`.
+//
+// It is generic over `T` as each command construction has their own Options type e.g. `ViewOptions`
+type NewCmdFunc[T any] func(f *cmdutil.Factory, runF func(*T) error) *cobra.Command
+
+// ExpectCommandToSupportJSONFields asserts that the provided command supports exactly the provided fields.
+// Ordering of the expected fields is not important.
+//
+// Make sure you are not pointing to the same slice of fields in the test and the implementation.
+// It can be a little tedious to rewrite the fields inline in the test but it's significantly more useful because:
+//   - It forces the test author to think about and convey exactly the expected fields for a command
+//   - It avoids accidentally adding fields to a command, and the test passing unintentionally
+func ExpectCommandToSupportJSONFields[T any](t *testing.T, fn NewCmdFunc[T], expectedFields []string) {
+	t.Helper()
+
+	actualFields := jsonFieldsFor(fn(&cmdutil.Factory{}, nil))
+	assert.Equal(t, len(actualFields), len(expectedFields), "expected number of fields to match")
+	require.ElementsMatch(t, expectedFields, actualFields)
+}