Fix IndexOutOfBoundsException in keyFields validation (#6748)

Author: BoD

libraries/apollo-ast/src/commonMain/kotlin/com/apollographql/apollo/ast/internal/SchemaValidationScope.kt

@@ -951,20 +951,22 @@ private fun ValidationScope.keyFields(
     return cached
   }
 
-  val (directives, interfaces) = when (typeDefinition) {
+  val (directives, allInterfaces) = when (typeDefinition) {
     is GQLObjectTypeDefinition -> typeDefinition.directives to typeDefinition.implementsInterfaces
     is GQLInterfaceTypeDefinition -> typeDefinition.directives to typeDefinition.implementsInterfaces
     else -> error("Unexpected type definition $typeDefinition")
   }
 
-  val interfacesKeyFields = interfaces.map { keyFields(typeDefinitions[it]!!, keyFieldsCache) }
-      .filter { it.isNotEmpty() }
+  val interfacesToKeyFields: Map<String, Set<String>> = allInterfaces.associate { it to keyFields(typeDefinitions[it]!!, keyFieldsCache) }
+      .filter { it.value.isNotEmpty() }
+  val interfaces = interfacesToKeyFields.keys.toList()
+  val interfacesKeyFields = interfacesToKeyFields.values.toList()
 
   val distinct = interfacesKeyFields.distinct()
   if (distinct.size > 1) {
-    val extra = interfaces.indices.map {
+    val extra = interfaces.indices.joinToString("\n") {
       "${interfaces[it]}: ${interfacesKeyFields[it]}"
-    }.joinToString("\n")
+    }
 
     registerIssue(
         message = "Apollo: Type '${typeDefinition.name}' cannot inherit different keys from different interfaces:\n$extra",
@@ -975,9 +977,9 @@ private fun ValidationScope.keyFields(
   val keyFields = directives.filter { originalDirectiveName(it.name) == TYPE_POLICY }.toKeyFields()
   val ret = if (keyFields.isNotEmpty()) {
     if (distinct.isNotEmpty()) {
-      val extra = interfaces.indices.map {
+      val extra = interfaces.indices.joinToString("\n") {
         "${interfaces[it]}: ${interfacesKeyFields[it]}"
-      }.joinToString("\n")
+      }
 
       registerIssue(
           message = "Type '${typeDefinition.name}' cannot have key fields since it implements the following interfaces which also have key fields: $extra",

libraries/apollo-compiler/src/test/validation/schema/typepolicy-clash.expected

@@ -0,0 +1,22 @@
+extend schema @link(url: "https://specs.apollo.dev/kotlin_labs/v0.5/", import: ["@typePolicy"])
+
+type Query {
+  x: Int
+}
+
+interface UnifiedEntity {
+  unifiedEntityId: ID!
+}
+
+interface OtherInterface {
+  otherField: String!
+}
+
+interface Video implements UnifiedEntity & OtherInterface {
+  unifiedEntityId: ID!
+  otherField: String!
+  videoId: ID!
+}
+
+extend interface UnifiedEntity @typePolicy(keyFields: "unifiedEntityId")
+extend interface Video @typePolicy(keyFields: "videoId")