Change AEP-158 to look for any repeated field

docs/rules/0158/response-repeated-first-field.md → docs/rules/0158/response-repeated-field.md

@@ -1,25 +1,24 @@
 ---
 rule:
   aep: 158
-  name: [core, '0158', response-repeated-first-field]
+  name: [core, '0158', response-repeated-field]
   summary: |
-    First field (by both position and field number) of Paginated RPCs' response
+    One field of a paginated RPCs' response
     should be repeated.
-permalink: /158/response-repeated-first-field
+permalink: /158/response-repeated-field
 redirect_from:
-  - /0158/response-repeated-first-field
+  - /0158/response-repeated-field
 ---
 
 # Paginated methods: Page token field
 
 This rule enforces that all `List` and `Search` methods have a repeatable field
-as a first field in the response message, as mandated in [AEP-158][].
+in the response message, as mandated in [AEP-158][].
 
 ## Details
 
 This rule looks at any message matching `List*Response` or `Search*Response`
-that has `next_page_token` field and complains if the first field (by both
-position and field number) is not repeated.
+that has `next_page_token` field and complains if there does not exist a field that is repeated.
 
 ## Examples
 

rules/aep0158/response_repeated_first_field.go → rules/aep0158/response_repeated_field.go

@@ -20,29 +20,21 @@ import (
 )
 
 var responseRepeatedFirstField = &lint.MessageRule{
-	Name:     lint.NewRuleName(158, "response-repeated-first-field"),
+	Name:     lint.NewRuleName(158, "response-repeated-field"),
 	RuleType: lint.NewRuleType(lint.MustRule),
 	OnlyIf: func(m *desc.MessageDescriptor) bool {
 		return isPaginatedResponseMessage(m) && len(m.GetFields()) > 0
 	},
 	LintMessage: func(m *desc.MessageDescriptor) []lint.Problem {
-		// Sanity check: Is the first field (positionally) and the field with
-		// an ID of 1 actually the same field?
-		if m.GetFields()[0] != m.FindFieldByNumber(1) {
-			return []lint.Problem{{
-				Message:    "The first field of paginated RPCs must have a protobuf ID of 1.",
-				Descriptor: m.GetFields()[0],
-			}}
+		for _, f := range m.GetFields() {
+			if(f.IsRepeated()) {
+				return nil;
+			}
 		}
 
-		// Make sure the field is repeated.
-		if !m.GetFields()[0].IsRepeated() {
-			return []lint.Problem{{
-				Message:    "The first field of a paginated response should be repeated.",
-				Descriptor: m.GetFields()[0],
-			}}
-		}
-
-		return nil
+		return []lint.Problem{{
+			Message:    "There does not exist a repeated field for pagination results.",
+			Descriptor: m,
+		}}
 	},
 }

rules/aep0158/response_repeated_first_field_test.go → rules/aep0158/response_repeated_field_test.go

@@ -29,7 +29,7 @@ func TestResponseRepeatedFirstField(t *testing.T) {
 	}{
 		{"Valid", "repeated Book books = 1;", "string next_page_token = 2;", nil},
 		{"SkippedZeroFields", "", "", nil},
-		{"InvalidFirstFieldsNoMatch", "string next_page_token = 2;", "repeated Book books = 1;", testutils.Problems{{Message: "protobuf ID"}}},
+		{"ProtobufIdIsNotOne", "string next_page_token = 1;", "repeated Book books = 2;", nil},
 		{"InvalidNotRepeated", "Book book = 1;", "string next_page_token = 2;", testutils.Problems{{Message: "repeated"}}},
 	}
 	for _, test := range tests {
@@ -45,14 +45,9 @@ func TestResponseRepeatedFirstField(t *testing.T) {
 				}
 			`, test)
 
-			// Determine the descriptor that a failing test will attach to.
-			if m := f.GetMessageTypes()[1]; len(m.GetFields()) > 0 {
-				test.problems.SetDescriptor(m.GetFields()[0])
-			}
-
 			// Run the lint rule and establish we get the correct problems.
 			problems := responseRepeatedFirstField.Lint(f)
-			if diff := test.problems.Diff(problems); diff != "" {
+			if diff := test.problems.SetDescriptor(f.GetMessageTypes()[1]).Diff(problems); diff != "" {
 				t.Errorf(diff)
 			}
 		})