Add helpful plugin errors

packages/core/parcel-bundler/.gitignore

@@ -5,7 +5,6 @@ test/input
 test/integration/**/elm-stuff
 test/integration/**/target
 test/integration/**/Cargo.lock
-test/**/node_modules
 test/**/yarn.lock
 test/**/package-lock.json
-test/integration/babel-plugin-autoinstall/package.json
+test/integration/babel-plugin-autoinstall/package.json

packages/core/parcel-bundler/src/Bundler.js

@@ -206,17 +206,23 @@ class Bundler extends EventEmitter {
       return;
     }
 
+    let lastDep;
     try {
       let deps = Object.assign({}, pkg.dependencies, pkg.devDependencies);
       for (let dep in deps) {
+        lastDep = dep;
         const pattern = /^(@.*\/)?parcel-plugin-.+/;
         if (pattern.test(dep)) {
           let plugin = await localRequire(dep, relative);
           await plugin(this);
         }
       }
     } catch (err) {
-      logger.warn(err);
+      logger.warn(
+        `Plugin ${lastDep} failed to initialize: ${err.stack ||
+          err.message ||
+          err}`
+      );
     }
   }
 

packages/core/parcel-bundler/src/Parser.js

@@ -1,4 +1,5 @@
 const path = require('path');
+const logger = require('@parcel/logger');
 const RawAsset = require('./assets/RawAsset');
 const GlobAsset = require('./assets/GlobAsset');
 const {isGlob} = require('./utils/glob');
@@ -74,7 +75,21 @@ class Parser {
     let extension = path.extname(filename).toLowerCase();
     let parser = this.extensions[extension] || RawAsset;
     if (typeof parser === 'string') {
-      parser = this.extensions[extension] = require(parser);
+      try {
+        parser = this.extensions[extension] = require(parser);
+      } catch (err) {
+        let relFilename = path.relative(process.cwd(), filename);
+        let relParserName = path.relative(process.cwd(), parser);
+        if (relParserName.slice(0, 12) === 'node_modules') {
+          relParserName = relParserName.slice(13);
+        }
+        logger.warn(
+          `Parser "${relParserName}" failed to initialize when processing ` +
+            `asset "${relFilename}". Threw the following error:\n` +
+            `${err.stack || err.message || err} falling back to RawAsset`
+        );
+        return RawAsset;
+      }
     }
 
     return parser;

packages/core/parcel-bundler/test/integration/plugins/package.json → packages/core/parcel-bundler/test/integration/plugins/test-plugin/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "parcel-test",
+  "name": "test-plugin-project",
   "private": true,
   "dependencies": {
     "parcel-plugin-test": "*"

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin-parser/index.js

@@ -0,0 +1 @@
+module.exports = require('./test.txt');

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin-parser/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "throwing-plugin-parser-project",
+  "private": true,
+  "dependencies": {
+    "parcel-plugin-test": "*"
+  }
+}

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin-parser/test.txt

@@ -0,0 +1 @@
+hello world

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin/index.js

@@ -0,0 +1 @@
+module.exports = require('./test.txt');

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "throwing-plugin-project",
+  "private": true,
+  "dependencies": {
+    "parcel-plugin-test": "*"
+  }
+}

packages/core/parcel-bundler/test/integration/plugins/throwing-plugin/test.txt

@@ -0,0 +1 @@
+hello world

packages/core/parcel-bundler/test/plugins.js

@@ -1,10 +1,14 @@
 const assert = require('assert');
+const sinon = require('sinon');
 const path = require('path');
+const logger = require('@parcel/logger');
 const {bundle, run, assertBundleTree} = require('@parcel/test-utils');
 
 describe('plugins', function() {
   it('should load plugins and apply custom asset type', async function() {
-    let b = await bundle(path.join(__dirname, '/integration/plugins/index.js'));
+    let b = await bundle(
+      path.join(__dirname, '/integration/plugins/test-plugin/index.js')
+    );
 
     await assertBundleTree(b, {
       name: 'index.js',
@@ -22,7 +26,10 @@ describe('plugins', function() {
 
   it('should load package.json from parent tree', async function() {
     let b = await bundle(
-      path.join(__dirname, '/integration/plugins/sub-folder/index.js')
+      path.join(
+        __dirname,
+        '/integration/plugins/test-plugin/sub-folder/index.js'
+      )
     );
 
     await assertBundleTree(b, {
@@ -38,4 +45,57 @@ describe('plugins', function() {
     let output = await run(b);
     assert.equal(output, 'hello world');
   });
+
+  it('log a warning if a plugin throws an exception during initialization', async function() {
+    sinon.stub(logger, 'warn');
+
+    let b = await bundle(
+      path.join(__dirname, '/integration/plugins/throwing-plugin/index.js')
+    );
+
+    await run(b);
+
+    sinon.assert.calledWith(
+      logger.warn,
+      sinon.match(
+        'Plugin parcel-plugin-test failed to initialize: Error: Plugin error'
+      )
+    );
+
+    logger.warn.restore();
+  });
+
+  it('log a warning if a parser throws an exception during initialization', async function() {
+    sinon.stub(logger, 'warn');
+
+    let b = await bundle(
+      path.join(
+        __dirname,
+        '/integration/plugins/throwing-plugin-parser/index.js'
+      )
+    );
+
+    await run(b);
+
+    sinon.assert.calledWith(
+      logger.warn,
+      sinon.match(
+        [
+          'Parser "test',
+          'integration',
+          'plugins',
+          'throwing-plugin-parser',
+          'node_modules',
+          'parcel-plugin-test',
+          'TextAsset.js" failed to initialize when processing asset "test',
+          'integration',
+          'plugins',
+          'throwing-plugin-parser',
+          'test.txt". ' + 'Threw the following error:\nError: Parser error'
+        ].join(path.sep)
+      )
+    );
+
+    logger.warn.restore();
+  });
 });