package.json

@@ -1,6 +1,6 @@
 {
   "name": "graphql",
-  "version": "15.6.1",
+  "version": "15.7.0",
   "description": "A Query Language and Runtime which can target any service.",
   "license": "MIT",
   "private": true,

src/error/GraphQLError.d.ts

@@ -4,6 +4,19 @@ import { ASTNode } from '../language/ast';
 import { Source } from '../language/source';
 import { SourceLocation } from '../language/location';
 
+/**
+ * Custom extensions
+ *
+ * @remarks
+ * Use a unique identifier name for your extension, for example the name of
+ * your library or project. Do not use a shortened identifier as this increases
+ * the risk of conflicts. We recommend you add at most one extension field,
+ * an object which can contain all the values you need.
+ */
+export interface GraphQLErrorExtensions {
+  [attributeName: string]: any;
+}
+
 /**
  * A GraphQLError describes an Error found during the parse, validate, or
  * execute phases of performing a GraphQL operation. In addition to a message
@@ -18,18 +31,9 @@ export class GraphQLError extends Error {
     positions?: Maybe<ReadonlyArray<number>>,
     path?: Maybe<ReadonlyArray<string | number>>,
     originalError?: Maybe<Error>,
-    extensions?: Maybe<{ [key: string]: any }>,
+    extensions?: Maybe<GraphQLErrorExtensions>,
   );
 
-  /**
-   * A message describing the Error for debugging purposes.
-   *
-   * Enumerable, and appears in the result of JSON.stringify().
-   *
-   * Note: should be treated as readonly, despite invariant usage.
-   */
-  message: string;
-
   /**
    * An array of { line, column } locations within the source GraphQL document
    * which correspond to this error.
@@ -72,12 +76,12 @@ export class GraphQLError extends Error {
   /**
    * The original error thrown from a field resolver during execution.
    */
-  readonly originalError: Maybe<Error>;
+  readonly originalError: Error | undefined;
 
   /**
    * Extension fields to add to the formatted error.
    */
-  readonly extensions: { [key: string]: any } | undefined;
+  readonly extensions: { [key: string]: any };
 }
 
 /**

src/error/GraphQLError.js

@@ -1,6 +1,3 @@
-// FIXME:
-// flowlint uninitialized-instance-property:off
-
 import isObjectLike from '../jsutils/isObjectLike';
 import { SYMBOL_TO_STRING_TAG } from '../polyfills/symbols';
 
@@ -17,15 +14,6 @@ import { printLocation, printSourceLocation } from '../language/printLocation';
  * GraphQL document and/or execution result that correspond to the Error.
  */
 export class GraphQLError extends Error {
-  /**
-   * A message describing the Error for debugging purposes.
-   *
-   * Enumerable, and appears in the result of JSON.stringify().
-   *
-   * Note: should be treated as readonly, despite invariant usage.
-   */
-  message: string;
-
   /**
    * An array of { line, column } locations within the source GraphQL document
    * which correspond to this error.
@@ -68,12 +56,12 @@ export class GraphQLError extends Error {
   /**
    * The original error thrown from a field resolver during execution.
    */
-  +originalError: ?Error;
+  +originalError: Error | void;
 
   /**
    * Extension fields to add to the formatted error.
    */
-  +extensions: { [key: string]: mixed, ... } | void;
+  +extensions: { [key: string]: mixed, ... };
 
   constructor(
     message: string,
@@ -86,103 +74,60 @@ export class GraphQLError extends Error {
   ) {
     super(message);
 
+    this.name = 'GraphQLError';
+    this.originalError = originalError ?? undefined;
+
     // Compute list of blame nodes.
-    const _nodes = Array.isArray(nodes)
-      ? nodes.length !== 0
-        ? nodes
-        : undefined
-      : nodes
-      ? [nodes]
-      : undefined;
+    this.nodes = undefinedIfEmpty(
+      Array.isArray(nodes) ? nodes : nodes ? [nodes] : undefined,
+    );
+
+    let nodeLocations = [];
+    for (const { loc } of this.nodes ?? []) {
+      if (loc != null) {
+        nodeLocations.push(loc);
+      }
+    }
+    nodeLocations = undefinedIfEmpty(nodeLocations);
 
     // Compute locations in the source for the given nodes/positions.
-    let _source = source;
-    if (!_source && _nodes) {
-      _source = _nodes[0].loc?.source;
-    }
+    this.source = source ?? nodeLocations?.[0].source;
 
-    let _positions = positions;
-    if (!_positions && _nodes) {
-      _positions = _nodes.reduce((list, node) => {
-        if (node.loc) {
-          list.push(node.loc.start);
-        }
-        return list;
-      }, []);
-    }
-    if (_positions && _positions.length === 0) {
-      _positions = undefined;
-    }
+    this.positions = positions ?? nodeLocations?.map((loc) => loc.start);
 
-    let _locations;
-    if (positions && source) {
-      _locations = positions.map((pos) => getLocation(source, pos));
-    } else if (_nodes) {
-      _locations = _nodes.reduce((list, node) => {
-        if (node.loc) {
-          list.push(getLocation(node.loc.source, node.loc.start));
-        }
-        return list;
-      }, []);
-    }
+    this.locations =
+      positions && source
+        ? positions.map((pos) => getLocation(source, pos))
+        : nodeLocations?.map((loc) => getLocation(loc.source, loc.start));
 
-    let _extensions = extensions;
-    if (_extensions == null && originalError != null) {
-      const originalExtensions = originalError.extensions;
-      if (isObjectLike(originalExtensions)) {
-        _extensions = originalExtensions;
-      }
+    this.path = path ?? undefined;
+
+    this.extensions = extensions ?? {};
+
+    const originalExtensions = originalError?.extensions;
+    if (isObjectLike(originalExtensions)) {
+      this.extensions = { ...originalExtensions };
     }
 
+    // By being enumerable, JSON.stringify will include bellow properties in the resulting output.
+    // This ensures that the simplest possible GraphQL service adheres to the spec.
     Object.defineProperties((this: any), {
-      name: { value: 'GraphQLError' },
-      message: {
-        value: message,
-        // By being enumerable, JSON.stringify will include `message` in the
-        // resulting output. This ensures that the simplest possible GraphQL
-        // service adheres to the spec.
-        enumerable: true,
-        writable: true,
-      },
+      message: { enumerable: true },
       locations: {
-        // Coercing falsy values to undefined ensures they will not be included
-        // in JSON.stringify() when not provided.
-        value: _locations ?? undefined,
-        // By being enumerable, JSON.stringify will include `locations` in the
-        // resulting output. This ensures that the simplest possible GraphQL
-        // service adheres to the spec.
-        enumerable: _locations != null,
+        enumerable: this.locations != null,
       },
       path: {
-        // Coercing falsy values to undefined ensures they will not be included
-        // in JSON.stringify() when not provided.
-        value: path ?? undefined,
-        // By being enumerable, JSON.stringify will include `path` in the
-        // resulting output. This ensures that the simplest possible GraphQL
-        // service adheres to the spec.
-        enumerable: path != null,
-      },
-      nodes: {
-        value: _nodes ?? undefined,
-      },
-      source: {
-        value: _source ?? undefined,
-      },
-      positions: {
-        value: _positions ?? undefined,
-      },
-      originalError: {
-        value: originalError,
+        enumerable: this.path != null,
       },
       extensions: {
-        // Coercing falsy values to undefined ensures they will not be included
-        // in JSON.stringify() when not provided.
-        value: _extensions ?? undefined,
-        // By being enumerable, JSON.stringify will include `path` in the
-        // resulting output. This ensures that the simplest possible GraphQL
-        // service adheres to the spec.
-        enumerable: _extensions != null,
+        enumerable:
+          this.extensions != null && Object.keys(this.extensions).length > 0,
       },
+      name: { enumerable: false },
+      nodes: { enumerable: false },
+      source: { enumerable: false },
+      positions: { enumerable: false },
+      originalError: { enumerable: false },
     });
 
     // Include (non-enumerable) stack trace.
@@ -218,6 +163,12 @@ export class GraphQLError extends Error {
   }
 }
 
+function undefinedIfEmpty<T>(
+  array: $ReadOnlyArray<T> | void,
+): $ReadOnlyArray<T> | void {
+  return array === undefined || array.length === 0 ? undefined : array;
+}
+
 /**
  * Prints a GraphQLError to a string, representing useful location information
  * about the error's position in the source.

src/error/__tests__/GraphQLError-test.js

@@ -28,10 +28,14 @@ describe('GraphQLError', () => {
     expect(new GraphQLError('str')).to.be.instanceof(GraphQLError);
   });
 
-  it('has a name, message, and stack trace', () => {
+  it('has a name, message, extensions, and stack trace', () => {
     const e = new GraphQLError('msg');
 
-    expect(e).to.include({ name: 'GraphQLError', message: 'msg' });
+    expect(e).to.deep.include({
+      name: 'GraphQLError',
+      message: 'msg',
+      extensions: {},
+    });
     expect(e.stack).to.be.a('string');
   });
 
@@ -96,6 +100,18 @@ describe('GraphQLError', () => {
     });
   });
 
+  it('converts node without location to undefined source, positions and locations', () => {
+    const documentNode = parse('{ foo }', { noLocation: true });
+
+    const e = new GraphQLError('msg', documentNode);
+    expect(e).to.deep.include({
+      nodes: [documentNode],
+      source: undefined,
+      positions: undefined,
+      locations: undefined,
+    });
+  });
+
   it('converts source and positions to locations', () => {
     const e = new GraphQLError('msg', null, source, [6]);
     expect(e).to.have.property('source', source);
@@ -106,29 +122,47 @@ describe('GraphQLError', () => {
     });
   });
 
-  it('serializes to include message', () => {
-    const e = new GraphQLError('msg');
-    expect(JSON.stringify(e)).to.equal('{"message":"msg"}');
-  });
+  it('serializes to include all standard fields', () => {
+    const eShort = new GraphQLError('msg');
+    expect(JSON.stringify(eShort, null, 2) + '\n').to.equal(dedent`
+      {
+        "message": "msg"
+      }
+    `);
 
-  it('serializes to include message and locations', () => {
-    const e = new GraphQLError('msg', fieldNode);
-    expect(JSON.stringify(e)).to.equal(
-      '{"message":"msg","locations":[{"line":2,"column":3}]}',
+    const path = ['path', 2, 'field'];
+    const extensions = { foo: 'bar' };
+    const eFull = new GraphQLError(
+      'msg',
+      fieldNode,
+      undefined,
+      undefined,
+      path,
+      undefined,
+      extensions,
     );
-  });
 
-  it('serializes to include path', () => {
-    const e = new GraphQLError('msg', null, null, null, [
-      'path',
-      3,
-      'to',
-      'field',
-    ]);
-    expect(e).to.have.deep.property('path', ['path', 3, 'to', 'field']);
-    expect(JSON.stringify(e)).to.equal(
-      '{"message":"msg","path":["path",3,"to","field"]}',
-    );
+    // We should try to keep order of fields stable
+    // Changing it wouldn't be breaking change but will fail some tests in other libraries.
+    expect(JSON.stringify(eFull, null, 2) + '\n').to.equal(dedent`
+      {
+        "message": "msg",
+        "locations": [
+          {
+            "line": 2,
+            "column": 3
+          }
+        ],
+        "path": [
+          "path",
+          2,
+          "field"
+        ],
+        "extensions": {
+          "foo": "bar"
+        }
+      }
+    `);
   });
 });
 

src/error/formatError.js

@@ -15,7 +15,7 @@ export function formatError(error: GraphQLError): GraphQLFormattedError {
   const path = error.path;
   const extensions = error.extensions;
 
-  return extensions
+  return extensions && Object.keys(extensions).length > 0
     ? { message, locations, path, extensions }
     : { message, locations, path };
 }

src/error/index.d.ts

@@ -1,4 +1,8 @@
-export { GraphQLError, printError } from './GraphQLError';
+export {
+  GraphQLError,
+  GraphQLErrorExtensions,
+  printError,
+} from './GraphQLError';
 export { syntaxError } from './syntaxError';
 export { locatedError } from './locatedError';
 export { formatError, GraphQLFormattedError } from './formatError';