Update buildScalar.js

Author: migueloller

src/build/__tests__/buildScalar-test.js

@@ -1,9 +1,11 @@
+/* @flow */
+
 import { GraphQLScalarType } from 'graphql/type';
 import { parse } from 'graphql/language';
 import buildScalar from '../buildScalar';
 
 describe('buildScalar()', () => {
-  const generateScalarAST = ({ description, name = 'Scalar' } = {}) => parse(`
+  const generateScalarNode = ({ description, name = 'Scalar' } = {}): any => parse(`
     # ${description === undefined ? '' : description}
     scalar ${name}
   `).definitions[0];
@@ -15,28 +17,28 @@ describe('buildScalar()', () => {
     parseLiteral,
   } = {}) => new GraphQLScalarType({ name, description, serialize, parseValue, parseLiteral });
 
-  it('should throw with without `serialize` in config', () => {
-    expect(() => buildScalar(generateScalarAST())).toThrow();
+  test('throws with without `serialize` in config', () => {
+    expect(() => buildScalar(generateScalarNode(), ({}: any))).toThrow();
   });
 
-  it('should work with `serialize` in config', () => {
-    const config = { serialize() {} };
-    expect(buildScalar(generateScalarAST(), config)).toEqual(generateScalarType(config));
+  test('builds with `serialize` in config', () => {
+    const config: any = { serialize() {} };
+    expect(buildScalar(generateScalarNode(), config)).toEqual(generateScalarType(config));
   });
 
-  it('should work with `serialize` in config and description in AST', () => {
-    const config = { description: 'A description', serialize() {} };
-    expect(buildScalar(generateScalarAST(config), config)).toEqual(generateScalarType(config));
+  test('builds with `serialize` in config and description in AST', () => {
+    const config: any = { description: 'A description', serialize() {} };
+    expect(buildScalar(generateScalarNode(config), config)).toEqual(generateScalarType(config));
   });
 
-  it('should work with `serialize`, `parseValue`, and `parseLiteral` in config', () => {
-    const config = { serialize() {}, parseValue() {}, parseLiteral() {} };
-    expect(buildScalar(generateScalarAST(), config)).toEqual(generateScalarType(config));
+  test('builds with `serialize`, `parseValue`, and `parseLiteral` in config', () => {
+    const config: any = { serialize() {}, parseValue() {}, parseLiteral() {} };
+    expect(buildScalar(generateScalarNode(), config)).toEqual(generateScalarType(config));
   });
 
-  it('should work with GraphQL scalar type', () => {
-    const config = { serialize() {} };
-    expect(buildScalar(generateScalarAST(), generateScalarType(config)))
+  test('builds with GraphQLScalarType', () => {
+    const config: any = { serialize() {} };
+    expect(buildScalar(generateScalarNode(), generateScalarType(config)))
       .toEqual(generateScalarType(config));
   });
 });

src/build/buildScalar.js

@@ -1,15 +1,25 @@
-import { GraphQLScalarType } from 'graphql/type';
+/* @flow */
+
+import type { ScalarTypeDefinitionNode } from 'graphql/language';
+import { type GraphQLScalarTypeConfig, GraphQLScalarType } from 'graphql/type';
 import { getDescription } from 'graphql/utilities/buildASTSchema';
 
-export default function buildScalar(scalarAST, config = {}) {
-  const {
-    serialize,
-    parseValue,
-    parseLiteral,
-    // eslint-disable-next-line no-underscore-dangle
-  } = config instanceof GraphQLScalarType ? config._scalarConfig : config;
-  const scalarTypeConfig = { name: scalarAST.name.value, serialize, parseValue, parseLiteral };
-  const description = getDescription(scalarAST);
+export default function buildScalar(
+  node: ScalarTypeDefinitionNode,
+  configOrType: GraphQLScalarTypeConfig<*, *> | GraphQLScalarType,
+): GraphQLScalarType {
+  const config = configOrType instanceof GraphQLScalarType
+    ? configOrType._scalarConfig // eslint-disable-line no-underscore-dangle
+    : configOrType;
+
+  // TODO: Warn if the user passed a name via the config in addition to the AST.
+
+  const scalarTypeConfig = { ...config, name: node.name.value };
+  const description = getDescription(node);
+
+  // TODO: Warn if the user passed a description via the config in addition to the AST.
+
   if (description) scalarTypeConfig.description = description;
+
   return new GraphQLScalarType(scalarTypeConfig);
 }