perf: allow skipping of field plan generation

src/execution/buildFieldPlan.ts

@@ -1,55 +1,39 @@
 import { getBySet } from '../jsutils/getBySet.js';
 import { isSameSet } from '../jsutils/isSameSet.js';
 
-import type { DeferUsage, FieldDetails } from './collectFields.js';
+import type {
+  DeferUsage,
+  FieldGroup,
+  GroupedFieldSet,
+} from './collectFields.js';
 
 export type DeferUsageSet = ReadonlySet<DeferUsage>;
 
-export interface FieldGroup {
-  fields: ReadonlyArray<FieldDetails>;
-  deferUsages?: DeferUsageSet | undefined;
+export interface FieldPlan {
+  groupedFieldSet: GroupedFieldSet;
+  newGroupedFieldSets: Map<DeferUsageSet, GroupedFieldSet>;
 }
 
-export type GroupedFieldSet = Map<string, FieldGroup>;
-
 export function buildFieldPlan(
-  fields: Map<string, ReadonlyArray<FieldDetails>>,
+  originalGroupedFieldSet: GroupedFieldSet,
   parentDeferUsages: DeferUsageSet = new Set<DeferUsage>(),
-): {
-  groupedFieldSet: GroupedFieldSet;
-  newGroupedFieldSets: Map<DeferUsageSet, GroupedFieldSet>;
-} {
-  const groupedFieldSet = new Map<
-    string,
-    {
-      fields: Array<FieldDetails>;
-      deferUsages: DeferUsageSet;
-    }
-  >();
+): FieldPlan {
+  const groupedFieldSet = new Map<string, FieldGroup>();
 
-  const newGroupedFieldSets = new Map<
-    DeferUsageSet,
-    Map<
-      string,
-      {
-        fields: Array<FieldDetails>;
-        deferUsages: DeferUsageSet;
-      }
-    >
-  >();
+  const newGroupedFieldSets = new Map<DeferUsageSet, Map<string, FieldGroup>>();
 
   const map = new Map<
     string,
     {
       deferUsageSet: DeferUsageSet;
-      fieldDetailsList: ReadonlyArray<FieldDetails>;
+      fieldGroup: FieldGroup;
     }
   >();
 
-  for (const [responseKey, fieldDetailsList] of fields) {
+  for (const [responseKey, fieldGroup] of originalGroupedFieldSet) {
     const deferUsageSet = new Set<DeferUsage>();
     let inOriginalResult = false;
-    for (const fieldDetails of fieldDetailsList) {
+    for (const fieldDetails of fieldGroup) {
       const deferUsage = fieldDetails.deferUsage;
       if (deferUsage === undefined) {
         inOriginalResult = true;
@@ -69,44 +53,21 @@ export function buildFieldPlan(
         }
       });
     }
-    map.set(responseKey, { deferUsageSet, fieldDetailsList });
+    map.set(responseKey, { deferUsageSet, fieldGroup });
   }
 
-  for (const [responseKey, { deferUsageSet, fieldDetailsList }] of map) {
+  for (const [responseKey, { deferUsageSet, fieldGroup }] of map) {
     if (isSameSet(deferUsageSet, parentDeferUsages)) {
-      let fieldGroup = groupedFieldSet.get(responseKey);
-      if (fieldGroup === undefined) {
-        fieldGroup = {
-          fields: [],
-          deferUsages: deferUsageSet,
-        };
-        groupedFieldSet.set(responseKey, fieldGroup);
-      }
-      fieldGroup.fields.push(...fieldDetailsList);
+      groupedFieldSet.set(responseKey, fieldGroup);
       continue;
     }
 
     let newGroupedFieldSet = getBySet(newGroupedFieldSets, deferUsageSet);
     if (newGroupedFieldSet === undefined) {
-      newGroupedFieldSet = new Map<
-        string,
-        {
-          fields: Array<FieldDetails>;
-          deferUsages: DeferUsageSet;
-          knownDeferUsages: DeferUsageSet;
-        }
-      >();
+      newGroupedFieldSet = new Map();
       newGroupedFieldSets.set(deferUsageSet, newGroupedFieldSet);
     }
-    let fieldGroup = newGroupedFieldSet.get(responseKey);
-    if (fieldGroup === undefined) {
-      fieldGroup = {
-        fields: [],
-        deferUsages: deferUsageSet,
-      };
-      newGroupedFieldSet.set(responseKey, fieldGroup);
-    }
-    fieldGroup.fields.push(...fieldDetailsList);
+    newGroupedFieldSet.set(responseKey, fieldGroup);
   }
 
   return {

src/execution/collectFields.ts

@@ -36,6 +36,10 @@ export interface FieldDetails {
   deferUsage: DeferUsage | undefined;
 }
 
+export type FieldGroup = ReadonlyArray<FieldDetails>;
+
+export type GroupedFieldSet = ReadonlyMap<string, FieldGroup>;
+
 interface CollectFieldsContext {
   schema: GraphQLSchema;
   fragments: ObjMap<FragmentDefinitionNode>;
@@ -61,7 +65,7 @@ export function collectFields(
   runtimeType: GraphQLObjectType,
   operation: OperationDefinitionNode,
 ): {
-  fields: Map<string, ReadonlyArray<FieldDetails>>;
+  groupedFieldSet: GroupedFieldSet;
   newDeferUsages: ReadonlyArray<DeferUsage>;
 } {
   const groupedFieldSet = new AccumulatorMap<string, FieldDetails>();
@@ -81,7 +85,7 @@ export function collectFields(
     groupedFieldSet,
     newDeferUsages,
   );
-  return { fields: groupedFieldSet, newDeferUsages };
+  return { groupedFieldSet, newDeferUsages };
 }
 
 /**
@@ -101,9 +105,9 @@ export function collectSubfields(
   variableValues: { [variable: string]: unknown },
   operation: OperationDefinitionNode,
   returnType: GraphQLObjectType,
-  fieldDetails: ReadonlyArray<FieldDetails>,
+  fieldGroup: FieldGroup,
 ): {
-  fields: Map<string, ReadonlyArray<FieldDetails>>;
+  groupedFieldSet: GroupedFieldSet;
   newDeferUsages: ReadonlyArray<DeferUsage>;
 } {
   const context: CollectFieldsContext = {
@@ -117,7 +121,7 @@ export function collectSubfields(
   const subGroupedFieldSet = new AccumulatorMap<string, FieldDetails>();
   const newDeferUsages: Array<DeferUsage> = [];
 
-  for (const fieldDetail of fieldDetails) {
+  for (const fieldDetail of fieldGroup) {
     const node = fieldDetail.node;
     if (node.selectionSet) {
       collectFieldsImpl(
@@ -131,7 +135,7 @@ export function collectSubfields(
   }
 
   return {
-    fields: subGroupedFieldSet,
+    groupedFieldSet: subGroupedFieldSet,
     newDeferUsages,
   };
 }