Move package resolution error to its own file

Reviewed By: rafeca

Differential Revision: D7180926

fbshipit-source-id: 24f14a662bbfc776c02093339f571db32af0be90

packages/metro-core/package.json

@@ -14,6 +14,7 @@
   "dependencies": {
     "jest-haste-map": "^22.4.2",
     "lodash.throttle": "^4.1.1",
+    "metro-resolver": "^0.31.0",
     "wordwrap": "^1.0.0"
   }
 }

packages/metro-core/src/errors/PackageResolutionError.js

@@ -0,0 +1,41 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ * @format
+ */
+
+'use strict';
+
+const {formatFileCandidates} = require('metro-resolver');
+const {InvalidPackageError} = require('metro-resolver');
+
+class PackageResolutionError extends Error {
+  originModulePath: string;
+  packageError: InvalidPackageError;
+  targetModuleName: string;
+
+  constructor(opts: {|
+    +originModulePath: string,
+    +packageError: InvalidPackageError,
+    +targetModuleName: string,
+  |}) {
+    const perr = opts.packageError;
+    super(
+      `While trying to resolve module \`${opts.targetModuleName}\` from file ` +
+        `\`${opts.originModulePath}\`, the package ` +
+        `\`${perr.packageJsonPath}\` was successfully found. However, ` +
+        `this package itself specifies ` +
+        `a \`main\` module field that could not be resolved (` +
+        `\`${perr.mainPrefixPath}\`. Indeed, none of these files exist:\n\n` +
+        `  * \`${formatFileCandidates(perr.fileCandidates)}\`\n` +
+        `  * \`${formatFileCandidates(perr.indexCandidates)}\``,
+    );
+    Object.assign(this, opts);
+  }
+}
+
+module.exports = PackageResolutionError;

packages/metro-core/src/errors/index.js

@@ -11,7 +11,9 @@
 'use strict';
 
 const AmbiguousModuleResolutionError = require('./AmbiguousModuleResolutionError');
+const PackageResolutionError = require('./PackageResolutionError');
 
 module.exports = {
   AmbiguousModuleResolutionError,
+  PackageResolutionError,
 };

packages/metro-core/src/index.js

@@ -12,6 +12,7 @@
 
 const AmbiguousModuleResolutionError = require('./errors/AmbiguousModuleResolutionError');
 const Logger = require('./Logger');
+const PackageResolutionError = require('./errors/PackageResolutionError');
 const Terminal = require('./Terminal');
 
 const formatBanner = require('./formatBanner');
@@ -19,6 +20,7 @@ const formatBanner = require('./formatBanner');
 module.exports = {
   AmbiguousModuleResolutionError,
   Logger,
+  PackageResolutionError,
   Terminal,
   formatBanner,
 };

packages/metro/src/node-haste/DependencyGraph/ResolutionRequest.js

@@ -14,7 +14,8 @@ const path = require('path');
 
 const {AmbiguousModuleResolutionError} = require('metro-core');
 const {DuplicateHasteCandidatesError} = require('jest-haste-map').ModuleMap;
-const {formatFileCandidates, InvalidPackageError} = require('metro-resolver');
+const {InvalidPackageError} = require('metro-resolver');
+const {PackageResolutionError} = require('metro-core');
 
 import type DependencyGraphHelpers from './DependencyGraphHelpers';
 import type {Options as TransformWorkerOptions} from '../../JSTransformer/worker';
@@ -61,7 +62,6 @@ type Options<TModule, TPackage> = {|
 class ResolutionRequest<TModule: Moduleish, TPackage: Packageish> {
   _immediateResolutionCache: {[key: string]: TModule, __proto__: null};
   _options: Options<TModule, TPackage>;
-  static PackageResolutionError: Class<PackageResolutionError>;
 
   constructor(options: Options<TModule, TPackage>) {
     this._options = options;
@@ -123,31 +123,4 @@ function getResolutionCacheKey(modulePath, depName) {
   return `${path.resolve(modulePath)}:${depName}`;
 }
 
-class PackageResolutionError extends Error {
-  originModulePath: string;
-  packageError: InvalidPackageError;
-  targetModuleName: string;
-
-  constructor(opts: {|
-    +originModulePath: string,
-    +packageError: InvalidPackageError,
-    +targetModuleName: string,
-  |}) {
-    const perr = opts.packageError;
-    super(
-      `While trying to resolve module \`${opts.targetModuleName}\` from file ` +
-        `\`${opts.originModulePath}\`, the package ` +
-        `\`${perr.packageJsonPath}\` was successfully found. However, ` +
-        `this package itself specifies ` +
-        `a \`main\` module field that could not be resolved (` +
-        `\`${perr.mainPrefixPath}\`. Indeed, none of these files exist:\n\n` +
-        `  * \`${formatFileCandidates(perr.fileCandidates)}\`\n` +
-        `  * \`${formatFileCandidates(perr.indexCandidates)}\``,
-    );
-    Object.assign(this, opts);
-  }
-}
-
-ResolutionRequest.PackageResolutionError = PackageResolutionError;
-
 module.exports = ResolutionRequest;