ESLint: mark unused arguments with underscore

.eslintrc.yml

@@ -189,8 +189,7 @@ rules:
   no-undef: error
   no-undef-init: error
   no-undefined: off
-  no-unused-vars:
-    [error, { vars: all, args: after-used, argsIgnorePattern: '^_' }]
+  no-unused-vars: [error, { vars: all, args: all, argsIgnorePattern: '^_' }]
   no-use-before-define: off
 
   # Node.js and CommonJS

src/__tests__/starWarsSchema.js

@@ -259,7 +259,7 @@ const queryType = new GraphQLObjectType({
           type: episodeEnum,
         },
       },
-      resolve: (root, { episode }) => getHero(episode),
+      resolve: (_source, { episode }) => getHero(episode),
     },
     human: {
       type: humanType,
@@ -269,7 +269,7 @@ const queryType = new GraphQLObjectType({
           type: GraphQLNonNull(GraphQLString),
         },
       },
-      resolve: (root, { id }) => getHuman(id),
+      resolve: (_source, { id }) => getHuman(id),
     },
     droid: {
       type: droidType,
@@ -279,7 +279,7 @@ const queryType = new GraphQLObjectType({
           type: GraphQLNonNull(GraphQLString),
         },
       },
-      resolve: (root, { id }) => getDroid(id),
+      resolve: (_source, { id }) => getDroid(id),
     },
   }),
 });

src/execution/__tests__/executor-test.js

@@ -932,7 +932,7 @@ describe('Execute: Handles basic execution tasks', () => {
         fields: {
           field: {
             type: GraphQLString,
-            resolve: (data, args) => inspect(args),
+            resolve: (_source, args) => inspect(args),
             args: {
               a: { type: GraphQLBoolean },
               b: { type: GraphQLBoolean },
@@ -1038,7 +1038,7 @@ describe('Execute: Handles basic execution tasks', () => {
     });
     const document = parse('{ foo }');
 
-    function fieldResolver(source, args, context, info) {
+    function fieldResolver(_source, _args, _context, info) {
       // For the purposes of test, just return the name of the field!
       return info.fieldName;
     }
@@ -1076,7 +1076,7 @@ describe('Execute: Handles basic execution tasks', () => {
     });
 
     let possibleTypes;
-    function typeResolver(source, context, info, abstractType) {
+    function typeResolver(_source, _context, info, abstractType) {
       // Resolver should be able to figure out all possible types on its own
       possibleTypes = info.schema.getPossibleTypes(abstractType);
 

src/execution/__tests__/mutations-test.js

@@ -44,7 +44,7 @@ class Root {
   }
 
   promiseAndFailToChangeTheNumber(): Promise<NumberHolder> {
-    return new Promise((resolve, reject) => {
+    return new Promise((_resolve, reject) => {
       process.nextTick(() => {
         reject(new Error('Cannot change the number'));
       });

src/execution/__tests__/union-interface-test.js

@@ -465,7 +465,7 @@ describe('Execute: Union and intersection types', () => {
       fields: {
         name: { type: GraphQLString },
       },
-      resolveType(obj, context, { schema: _schema, rootValue }) {
+      resolveType(_source, context, { schema: _schema, rootValue }) {
         encounteredContext = context;
         encounteredSchema = _schema;
         encounteredRootValue = rootValue;

src/language/__tests__/visitor-test.js

@@ -66,11 +66,11 @@ describe('Visitor', () => {
     const ast = parse('{ a }', { noLocation: true });
 
     visit(ast, {
-      enter(node, key, parent, path) {
+      enter(_node, _key, _parent, path) {
         checkVisitorFnArgs(ast, arguments);
         visited.push(['enter', path.slice()]);
       },
-      leave(node, key, parent, path) {
+      leave(_node, _key, _parent, path) {
         checkVisitorFnArgs(ast, arguments);
         visited.push(['leave', path.slice()]);
       },
@@ -95,7 +95,7 @@ describe('Visitor', () => {
     const visitedNodes = [];
 
     visit(ast, {
-      enter(node, key, parent, path, ancestors) {
+      enter(node, key, parent, _path, ancestors) {
         const inArray = typeof key === 'number';
         if (inArray) {
           visitedNodes.push(parent);
@@ -105,7 +105,7 @@ describe('Visitor', () => {
         const expectedAncestors = visitedNodes.slice(0, -2);
         expect(ancestors).to.deep.equal(expectedAncestors);
       },
-      leave(node, key, parent, path, ancestors) {
+      leave(_node, key, _parent, _path, ancestors) {
         const expectedAncestors = visitedNodes.slice(0, -2);
         expect(ancestors).to.deep.equal(expectedAncestors);
 

src/type/__tests__/enumType-test.js

@@ -40,7 +40,7 @@ const QueryType = new GraphQLObjectType({
         fromInt: { type: GraphQLInt },
         fromString: { type: GraphQLString },
       },
-      resolve(value, { fromEnum, fromInt, fromString }) {
+      resolve(_source, { fromEnum, fromInt, fromString }) {
         return fromInt !== undefined
           ? fromInt
           : fromString !== undefined
@@ -54,7 +54,7 @@ const QueryType = new GraphQLObjectType({
         fromEnum: { type: ColorType },
         fromInt: { type: GraphQLInt },
       },
-      resolve(value, { fromEnum, fromInt }) {
+      resolve(_source, { fromEnum, fromInt }) {
         return fromInt !== undefined ? fromInt : fromEnum;
       },
     },
@@ -70,7 +70,7 @@ const QueryType = new GraphQLObjectType({
         provideGoodValue: { type: GraphQLBoolean },
         provideBadValue: { type: GraphQLBoolean },
       },
-      resolve(value, { fromEnum, provideGoodValue, provideBadValue }) {
+      resolve(_source, { fromEnum, provideGoodValue, provideBadValue }) {
         if (provideGoodValue) {
           // Note: this is one of the references of the internal values which
           // ComplexEnum allows.
@@ -93,9 +93,7 @@ const MutationType = new GraphQLObjectType({
     favoriteEnum: {
       type: ColorType,
       args: { color: { type: ColorType } },
-      resolve(value, { color }) {
-        return color;
-      },
+      resolve: (_source, { color }) => color,
     },
   },
 });
@@ -106,9 +104,7 @@ const SubscriptionType = new GraphQLObjectType({
     subscribeToEnum: {
       type: ColorType,
       args: { color: { type: ColorType } },
-      resolve(value, { color }) {
-        return color;
-      },
+      resolve: (_source, { color }) => color,
     },
   },
 });

src/type/introspection.js

@@ -247,7 +247,7 @@ export const __Type = new GraphQLObjectType({
       },
       possibleTypes: {
         type: GraphQLList(GraphQLNonNull(__Type)),
-        resolve(type, args, context, { schema }) {
+        resolve(type, _args, _context, { schema }) {
           if (isAbstractType(type)) {
             return schema.getPossibleTypes(type);
           }
@@ -437,7 +437,7 @@ export const SchemaMetaFieldDef: GraphQLField<mixed, mixed> = {
   type: GraphQLNonNull(__Schema),
   description: 'Access the current type schema of this server.',
   args: [],
-  resolve: (source, args, context, { schema }) => schema,
+  resolve: (_source, _args, _context, { schema }) => schema,
   deprecationReason: undefined,
   extensions: undefined,
   astNode: undefined,
@@ -457,7 +457,7 @@ export const TypeMetaFieldDef: GraphQLField<mixed, mixed> = {
       astNode: undefined,
     },
   ],
-  resolve: (source, { name }, context, { schema }) => schema.getType(name),
+  resolve: (_source, { name }, _context, { schema }) => schema.getType(name),
   deprecationReason: undefined,
   extensions: undefined,
   astNode: undefined,
@@ -468,7 +468,7 @@ export const TypeNameMetaFieldDef: GraphQLField<mixed, mixed> = {
   type: GraphQLNonNull(GraphQLString),
   description: 'The name of the current Object type at runtime.',
   args: [],
-  resolve: (source, args, context, { parentType }) => parentType.name,
+  resolve: (_source, _args, _context, { parentType }) => parentType.name,
   deprecationReason: undefined,
   extensions: undefined,
   astNode: undefined,

src/validation/rules/FieldsOnCorrectType.js

@@ -110,7 +110,7 @@ function getSuggestedTypeNames(
  * that may be the result of a typo.
  */
 function getSuggestedFieldNames(
-  schema: GraphQLSchema,
+  _schema: GraphQLSchema,
   type: GraphQLOutputType,
   fieldName: string,
 ): Array<string> {

src/validation/rules/KnownDirectives.js

@@ -40,7 +40,7 @@ export function KnownDirectives(
   }
 
   return {
-    Directive(node, key, parent, path, ancestors) {
+    Directive(node, _key, _parent, _path, ancestors) {
       const name = node.name.value;
       const locations = locationsMap[name];