Add React error overlay and HMR source maps

packages/core/integration-tests/test/hmr.js

@@ -10,6 +10,7 @@ import {
   overlayFS,
   sleep,
   run,
+  request,
 } from '@parcel/test-utils';
 import WebSocket from 'ws';
 import json5 from 'json5';
@@ -110,6 +111,7 @@ describe('hmr', function () {
     return {
       outputs: JSON.parse(JSON.stringify(outputs)),
       reloaded,
+      bundleGraph,
     };
   }
 
@@ -157,10 +159,12 @@ describe('hmr', function () {
       assert.equal(message.type, 'update');
 
       // Figure out why output doesn't change...
-      let localAsset = message.assets.find(
-        asset => asset.output === 'exports.a = 5;\nexports.b = 5;\n',
+      let localAsset = message.assets.find(asset =>
+        asset.output.includes('exports.a = 5;\nexports.b = 5;\n'),
       );
       assert(!!localAsset);
+      assert(localAsset.output.includes('//# sourceMappingURL'));
+      assert(localAsset.output.includes('//# sourceURL'));
     });
 
     it('should emit an HMR update for all new dependencies along with the changed file', async function () {
@@ -331,6 +335,31 @@ describe('hmr', function () {
 
       assert.equal(message.type, 'update');
     });
+
+    it('should respond to requests for assets by id', async function () {
+      let port = await getPort();
+      let b = bundler(path.join(__dirname, '/input/index.js'), {
+        serveOptions: {port},
+        hmrOptions: {port},
+        inputFS: overlayFS,
+        config,
+      });
+
+      subscription = await b.watch();
+      let event = await getNextBuild(b);
+
+      let bundleGraph = nullthrows(event.bundleGraph);
+      let asset = nullthrows(bundleGraph.getBundles()[0].getMainEntry());
+      let contents = await request('/__parcel_hmr/' + asset.id, port);
+      let publicId = nullthrows(bundleGraph).getAssetPublicId(asset);
+      assert(
+        contents.startsWith(
+          `parcelHotUpdate['${publicId}'] = function (require, module, exports) {`,
+        ),
+      );
+      assert(contents.includes('//# sourceMappingURL'));
+      assert(contents.includes('//# sourceURL'));
+    });
   });
 
   // TODO: add test for 4532 (`require` call in modified asset in child bundle where HMR runtime runs in parent bundle)
@@ -548,6 +577,29 @@ module.hot.dispose((data) => {
       assert.notEqual(url.search, search);
     });
 
+    it('should have correct source locations in errors', async function () {
+      let {outputs, bundleGraph} = await testHMRClient(
+        'hmr-accept-self',
+        () => {
+          return {
+            'local.js': 'output(new Error().stack);',
+          };
+        },
+      );
+
+      let asset = bundleGraph
+        .getBundles()[0]
+        .traverseAssets((asset, _, actions) => {
+          if (asset.filePath.endsWith('local.js')) {
+            actions.stop();
+            return asset;
+          }
+        });
+
+      let stack = outputs.pop();
+      assert(stack.includes('/__parcel_hmr/' + nullthrows(asset).id));
+    });
+
     /*
     it.skip('should accept HMR updates in the runtime after an initial error', async function() {
       await fs.mkdirp(path.join(__dirname, '/input'));

packages/core/integration-tests/test/server.js

@@ -10,8 +10,8 @@ import {
   outputFS,
   overlayFS,
   ncp,
+  request as get,
 } from '@parcel/test-utils';
-import http from 'http';
 import https from 'https';
 import getPort from 'get-port';
 import type {BuildEvent} from '@parcel/types';
@@ -22,32 +22,6 @@ const config = path.join(
   './integration/custom-configs/.parcelrc-dev-server',
 );
 
-function get(file, port, client = http) {
-  return new Promise((resolve, reject) => {
-    // $FlowFixMe
-    client.get(
-      {
-        hostname: 'localhost',
-        port: port,
-        path: file,
-        rejectUnauthorized: false,
-      },
-      res => {
-        res.setEncoding('utf8');
-        let data = '';
-        res.on('data', c => (data += c));
-        res.on('end', () => {
-          if (res.statusCode !== 200) {
-            return reject({statusCode: res.statusCode, data});
-          }
-
-          resolve(data);
-        });
-      },
-    );
-  });
-}
-
 describe('server', function () {
   let subscription;
 

packages/core/test-utils/src/utils.js

@@ -27,6 +27,8 @@ import nullthrows from 'nullthrows';
 import {parser as postHtmlParse} from 'posthtml-parser';
 import postHtml from 'posthtml';
 import EventEmitter from 'events';
+import http from 'http';
+import https from 'https';
 
 import {makeDeferredWithPromise, normalizeSeparators} from '@parcel/utils';
 import _chalk from 'chalk';
@@ -734,6 +736,8 @@ function prepareBrowserContext(
       },
       URL,
       Worker: createWorkerClass(bundle.filePath),
+      addEventListener() {},
+      removeEventListener() {},
     },
     globals,
   );
@@ -1157,3 +1161,33 @@ export async function assertNoFilePathInCache(
     }
   }
 }
+
+export function request(
+  file: string,
+  port: number,
+  client: typeof http | typeof https = http,
+): Promise<string> {
+  return new Promise((resolve, reject) => {
+    // $FlowFixMe
+    client.get(
+      {
+        hostname: 'localhost',
+        port: port,
+        path: file,
+        rejectUnauthorized: false,
+      },
+      res => {
+        res.setEncoding('utf8');
+        let data = '';
+        res.on('data', c => (data += c));
+        res.on('end', () => {
+          if (res.statusCode !== 200) {
+            return reject({statusCode: res.statusCode, data});
+          }
+
+          resolve(data);
+        });
+      },
+    );
+  });
+}

packages/core/utils/src/prettyDiagnostic.js

@@ -10,10 +10,18 @@ import nullthrows from 'nullthrows';
 // $FlowFixMe
 import terminalLink from 'terminal-link';
 
+export type FormattedCodeFrame = {|
+  location: string,
+  code: string,
+|};
+
 export type AnsiDiagnosticResult = {|
   message: string,
   stack: string,
+  /** A formatted string containing all code frames, including their file locations. */
   codeframe: string,
+  /** A list of code frames with highlighted code and file locations separately. */
+  frames: Array<FormattedCodeFrame>,
   hints: Array<string>,
   documentation: string,
 |};
@@ -39,6 +47,7 @@ export default async function prettyDiagnostic(
       (skipFormatting ? message : mdAnsi(message)),
     stack: '',
     codeframe: '',
+    frames: [],
     hints: [],
     documentation: '',
   };
@@ -69,16 +78,20 @@ export default async function prettyDiagnostic(
         });
       }
 
-      result.codeframe +=
+      let location =
         typeof filePath !== 'string'
           ? ''
-          : chalk.gray.underline(
-              `${filePath}:${highlights[0].start.line}:${highlights[0].start.column}\n`,
-            );
+          : `${filePath}:${highlights[0].start.line}:${highlights[0].start.column}`;
+      result.codeframe += location ? chalk.gray.underline(location) + '\n' : '';
       result.codeframe += formattedCodeFrame;
       if (codeFrame !== codeFrames[codeFrames.length - 1]) {
         result.codeframe += '\n\n';
       }
+
+      result.frames.push({
+        location,
+        code: formattedCodeFrame,
+      });
     }
   }
 

packages/reporters/dev-server/package.json

@@ -38,6 +38,8 @@
     "connect": "^3.7.0",
     "ejs": "^3.1.6",
     "http-proxy-middleware": "^2.0.1",
+    "launch-editor": "^2.3.0",
+    "mime-types": "2.1.18",
     "nullthrows": "^1.1.1",
     "serve-handler": "^6.0.0",
     "ws": "^7.0.0"

packages/reporters/dev-server/src/HMRServer.js

@@ -1,16 +1,25 @@
 // @flow
 
-import type {BuildSuccessEvent, Dependency, PluginOptions} from '@parcel/types';
+import type {
+  BuildSuccessEvent,
+  Dependency,
+  PluginOptions,
+  BundleGraph,
+  PackagedBundle,
+  Asset,
+} from '@parcel/types';
 import type {Diagnostic} from '@parcel/diagnostic';
 import type {AnsiDiagnosticResult} from '@parcel/utils';
 import type {ServerError, HMRServerOptions} from './types.js.flow';
 
 import WebSocket from 'ws';
 import invariant from 'assert';
 import {ansiHtml, prettyDiagnostic, PromiseQueue} from '@parcel/utils';
+import {HMR_ENDPOINT} from './Server';
 
 export type HMRAsset = {|
   id: string,
+  url: string,
   type: string,
   output: string,
   envHash: string,
@@ -26,7 +35,7 @@ export type HMRMessage =
       type: 'error',
       diagnostics: {|
         ansi: Array<AnsiDiagnosticResult>,
-        html: Array<AnsiDiagnosticResult>,
+        html: Array<$Rest<AnsiDiagnosticResult, {|codeframe: string|}>>,
       |},
     |};
 
@@ -81,7 +90,10 @@ export default class HMRServer {
           return {
             message: ansiHtml(d.message),
             stack: ansiHtml(d.stack),
-            codeframe: ansiHtml(d.codeframe),
+            frames: d.frames.map(f => ({
+              location: f.location,
+              code: ansiHtml(f.code),
+            })),
             hints: d.hints.map(hint => ansiHtml(hint)),
             documentation: diagnostics[i].documentationURL ?? '',
           };
@@ -141,9 +153,13 @@ export default class HMRServer {
 
         return {
           id: event.bundleGraph.getAssetPublicId(asset),
+          url: getSourceURL(event.bundleGraph, asset),
           type: asset.type,
           // No need to send the contents of non-JS assets to the client.
-          output: asset.type === 'js' ? await asset.getCode() : '',
+          output:
+            asset.type === 'js'
+              ? await getHotAssetContents(event.bundleGraph, asset)
+              : '',
           envHash: asset.env.id,
           depsByBundle,
         };
@@ -185,3 +201,34 @@ function getSpecifier(dep: Dependency): string {
 
   return dep.specifier;
 }
+
+export async function getHotAssetContents(
+  bundleGraph: BundleGraph<PackagedBundle>,
+  asset: Asset,
+): Promise<string> {
+  let output = await asset.getCode();
+  if (asset.type === 'js') {
+    let publicId = bundleGraph.getAssetPublicId(asset);
+    output = `parcelHotUpdate['${publicId}'] = function (require, module, exports) {${output}}`;
+  }
+
+  let sourcemap = await asset.getMap();
+  if (sourcemap) {
+    let sourcemapStringified = await sourcemap.stringify({
+      format: 'inline',
+      sourceRoot: '/__parcel_source_root/',
+      // $FlowFixMe
+      fs: asset.fs,
+    });
+
+    invariant(typeof sourcemapStringified === 'string');
+    output += `\n//# sourceMappingURL=${sourcemapStringified}`;
+    output += `\n//# sourceURL=${getSourceURL(bundleGraph, asset)}\n`;
+  }
+
+  return output;
+}
+
+function getSourceURL(bundleGraph, asset) {
+  return HMR_ENDPOINT + asset.id;
+}