names match: tighten validation of inlining and metadata

Because "" and "metadata" were excluded from checking, some incorrect
usage of those were not detected.

Also, naming ListMeta or ObjectMeta "listMeta" or "objectMeta" was allowed
because the names match, even though by convention the name should have
been "metadata".

pkg/generators/rules/names_match.go

@@ -32,14 +32,6 @@ var (
 		"-",
 	)
 
-	// Blacklist of JSON names that should skip match evaluation
-	jsonNameBlacklist = sets.NewString(
-		// Empty name is used for inline struct field (e.g. metav1.TypeMeta)
-		"",
-		// Special case for object and list meta
-		"metadata",
-	)
-
 	// List of substrings that aren't allowed in Go name and JSON name
 	disallowedNameSubstrings = sets.NewString(
 		// Underscore is not allowed in either name
@@ -73,12 +65,11 @@ is also considered matched.
 
 	HTTPJSONSpec   httpjsonSpec   true
 
-NOTE: JSON names in jsonNameBlacklist should skip evaluation
+NOTE: an empty JSON name is valid only for inlined structs or pointer to structs.
+It cannot be empty for anything else because capitalization must be set explicitly.
 
-	                              true
-	podSpec                       true
-	podSpec        -              true
-	podSpec        metadata       true
+NOTE: metav1.ListMeta and metav1.ObjectMeta by convention must have "metadata" as name.
+Other fields may have that JSON name if the field name matches.
 */
 type NamesMatch struct{}
 
@@ -109,14 +100,30 @@ func (n *NamesMatch) Validate(t *types.Type) ([]string, error) {
 				continue
 			}
 			jsonName := strings.Split(jsonTag, ",")[0]
-			if !namesMatch(goName, jsonName) {
+			if !nameIsOkay(m, jsonName) {
 				fields = append(fields, goName)
 			}
 		}
 	}
 	return fields, nil
 }
 
+func nameIsOkay(member types.Member, jsonName string) bool {
+	if jsonName == "" {
+		return member.Type.Kind == types.Struct ||
+			member.Type.Kind == types.Pointer && member.Type.Underlying.Kind == types.Struct
+	}
+
+	typeName := member.Type.String()
+	switch typeName {
+	case "k8s.io/apimachinery/pkg/apis/meta/v1.ListMeta",
+		"k8s.io/apimachinery/pkg/apis/meta/v1.ObjectMeta":
+		return jsonName == "metadata"
+	}
+
+	return namesMatch(member.Name, jsonName)
+}
+
 // namesMatch evaluates if goName and jsonName match the API rule
 // TODO: Use an off-the-shelf CamelCase solution instead of implementing this logic. The following existing
 //
@@ -129,9 +136,6 @@ func (n *NamesMatch) Validate(t *types.Type) ([]string, error) {
 //		 about why they don't satisfy our need. What we need can be a function that detects an acronym at the
 //		 beginning of a string.
 func namesMatch(goName, jsonName string) bool {
-	if jsonNameBlacklist.Has(jsonName) {
-		return true
-	}
 	if !isAllowedName(goName) || !isAllowedName(jsonName) {
 		return false
 	}

pkg/generators/rules/names_match_test.go

@@ -264,36 +264,7 @@ func TestNamesMatch(t *testing.T) {
 			},
 			expected: []string{"PodSpec"},
 		},
-		// NOTE: JSON names in jsonNameBlacklist should skip evaluation
-		// {"", "", true},
-		{
-			name: "unspecified",
-			t: &types.Type{
-				Kind: types.Struct,
-				Members: []types.Member{
-					{
-						Name: "",
-						Tags: `json:""`,
-					},
-				},
-			},
-			expected: []string{},
-		},
-		// {"podSpec", "", true},
-		{
-			name: "blacklist_empty",
-			t: &types.Type{
-				Kind: types.Struct,
-				Members: []types.Member{
-					{
-						Name: "podSpec",
-						Tags: `json:""`,
-					},
-				},
-			},
-			expected: []string{},
-		},
-		// {"podSpec", "metadata", true},
+		// {"podSpec", "metadata", false},
 		{
 			name: "blacklist_metadata",
 			t: &types.Type{
@@ -305,7 +276,7 @@ func TestNamesMatch(t *testing.T) {
 					},
 				},
 			},
-			expected: []string{},
+			expected: []string{"podSpec"},
 		},
 		{
 			name: "non_struct",
@@ -399,8 +370,8 @@ func TestNamesMatch(t *testing.T) {
 				},
 			},
 			expected: []string{
-				// "Int", TODO: should be reported!
-				// "IntPtr", TODO: should be reported!
+				"Int",
+				"IntPtr",
 			},
 		},
 		{
@@ -426,9 +397,9 @@ func TestNamesMatch(t *testing.T) {
 				},
 			},
 			expected: []string{
-				// "ListMeta", TODO: should be reported!
-				// "ObjectMeta", TODO: should be reported!
-				// "SomeStruct", TODO: should be reported!
+				"ListMeta",
+				"ObjectMeta",
+				"SomeStruct",
 			},
 		},
 		{
@@ -454,7 +425,7 @@ func TestNamesMatch(t *testing.T) {
 				},
 			},
 			expected: []string{
-				// "SomeStruct", TODO: should be reported!
+				"SomeStruct",
 			},
 		},
 	}