Support Package Resolution Configuration files.

pkg/compiler/lib/src/apiimpl.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library leg_apiimpl;
 
 import 'dart:async';
+import 'dart:convert';
 
 import '../compiler.dart' as api;
 import 'dart2jslib.dart' as leg;
 import 'tree/tree.dart' as tree;
 import 'elements/elements.dart' as elements;
 import 'package:_internal/libraries.dart' hide LIBRARIES;
 import 'package:_internal/libraries.dart' as library_info show LIBRARIES;
 import 'io/source_file.dart';
+import 'package:package_config/packages.dart';
+import 'package:package_config/packages_file.dart' as pkgs;
+import 'package:package_config/src/packages_impl.dart'
+    show NonFilePackagesDirectoryPackages, MapPackages;
+import 'package:package_config/src/util.dart' show checkValidPackageUri;
 
 const bool forceIncrementalSupport =
     const bool.fromEnvironment('DART2JS_EXPERIMENTAL_INCREMENTAL_SUPPORT');
 
 class Compiler extends leg.Compiler {
   api.CompilerInputProvider provider;
   api.DiagnosticHandler handler;
   final Uri libraryRoot;
+  final Uri packageConfig;
   final Uri packageRoot;
+  final api.PackagesDiscoveryProvider packagesDiscoveryProvider;
+  Packages packages;
   List<String> options;
   Map<String, dynamic> environment;
   bool mockableLibraryUsed = false;
   final Set<String> allowedLibraryCategories;
 
   leg.GenericTask userHandlerTask;
   leg.GenericTask userProviderTask;
+  leg.GenericTask userPackagesDiscoveryTask;
 
   Compiler(this.provider,
            api.CompilerOutputProvider outputProvider,
            this.handler,
            this.libraryRoot,
            this.packageRoot,
            List<String> options,
-           this.environment)
+           this.environment,
+           [this.packageConfig,
+            this.packagesDiscoveryProvider])
       : this.options = options,
         this.allowedLibraryCategories = getAllowedLibraryCategories(options),
         super(
             outputProvider: outputProvider,
             enableTypeAssertions: hasOption(options, '--enable-checked-mode'),
             enableUserAssertions: hasOption(options, '--enable-checked-mode'),
             trustTypeAnnotations:
                 hasOption(options, '--trust-type-annotations'),
             trustPrimitives:
                 hasOption(options, '--trust-primitives'),
@@ skipping 39 matching lines @@
             generateCodeWithCompileTimeErrors:
                 hasOption(options, '--generate-code-with-compile-time-errors'),
             testMode: hasOption(options, '--test-mode'),
             allowNativeExtensions:
                 hasOption(options, '--allow-native-extensions'),
             enableNullAwareOperators:
                 hasOption(options, '--enable-null-aware-operators')) {
     tasks.addAll([
         userHandlerTask = new leg.GenericTask('Diagnostic handler', this),
         userProviderTask = new leg.GenericTask('Input provider', this),
+        userPackagesDiscoveryTask =
+            new leg.GenericTask('Package discovery', this),
     ]);
     if (libraryRoot == null) {
       throw new ArgumentError("[libraryRoot] is null.");
     }
     if (!libraryRoot.path.endsWith("/")) {
       throw new ArgumentError("[libraryRoot] must end with a /.");
     }
-    if (packageRoot == null) {
-      throw new ArgumentError("[packageRoot] is null.");
+    if (packageRoot != null && packageConfig != null) {
+      throw new ArgumentError("Only one of [packageRoot] or [packageConfig] "
+                              "may be given.");
     }
-    if (!packageRoot.path.endsWith("/")) {
+    if (packageRoot != null && !packageRoot.path.endsWith("/")) {
       throw new ArgumentError("[packageRoot] must end with a /.");
     }
     if (!analyzeOnly) {
       if (allowNativeExtensions) {
         throw new ArgumentError(
             "--allow-native-extensions is only supported in combination with "
             "--analyze-only");
       }
     }
   }
@@ skipping 33 matching lines @@
     result.add('Internal');
     return new Set<String>.from(result);
   }
 
   static bool hasOption(List<String> options, String option) {
     return options.indexOf(option) >= 0;
   }
 
   // TODO(johnniwinther): Merge better with [translateDartUri] when
   // [scanBuiltinLibrary] is removed.
-  String lookupLibraryPath(String dartLibraryName) {
-    LibraryInfo info = lookupLibraryInfo(dartLibraryName);
+  String lookupLibraryPath(LibraryInfo info) {
     if (info == null) return null;
     if (!info.isDart2jsLibrary) return null;
     if (!allowedLibraryCategories.contains(info.category)) return null;
     String path = info.dart2jsPath;
     if (path == null) {
       path = info.path;
     }
     return "lib/$path";
   }
 
@@ skipping 43 matching lines @@
         withCurrentElement(element, () {
           reportError(
               node,
               leg.MessageKind.READ_SCRIPT_ERROR,
               {'uri': readableUri, 'exception': exception});
         });
       }
     }
 
     Uri resourceUri = translateUri(node, readableUri);
+    if (resourceUri == null) return synthesizeScript(node, readableUri);
     if (resourceUri.scheme == 'dart-ext') {
       if (!allowNativeExtensions) {
         withCurrentElement(element, () {
           reportError(node, leg.MessageKind.DART_EXT_NOT_SUPPORTED);
         });
       }
       return synthesizeScript(node, readableUri);
     }
 
     // TODO(johnniwinther): Wrap the result from [provider] in a specialized
@@ skipping 15 matching lines @@
       // relative URIs mentioned in the script. See the comment on
       // [LibraryLoader] for more details.
       return new leg.Script(readableUri, resourceUri, sourceFile);
     }).catchError((error) {
       reportReadError(error);
       return synthesizeScript(node, readableUri);
     });
   }
 
   Future<leg.Script> synthesizeScript(leg.Spannable node, Uri readableUri) {
-    Uri resourceUri = translateUri(node, readableUri);
     return new Future.value(
         new leg.Script(
-            readableUri, resourceUri,
+            readableUri, readableUri,
             new StringSourceFile.fromUri(
-                resourceUri,
+                readableUri,
                 "// Synthetic source file generated for '$readableUri'."),
             isSynthesized: true));
   }
 
   /**
    * Translates a readable URI into a resource URI.
    *
    * See [LibraryLoader] for terminology on URIs.
    */
   Uri translateUri(leg.Spannable node, Uri readableUri) {
     switch (readableUri.scheme) {
       case 'package': return translatePackageUri(node, readableUri);
       default: return readableUri;
     }
   }
 
   Uri translateDartUri(elements.LibraryElement importingLibrary,
                        Uri resolvedUri, tree.Node node) {
     LibraryInfo libraryInfo = lookupLibraryInfo(resolvedUri.path);
-    String path = lookupLibraryPath(resolvedUri.path);
+    String path = lookupLibraryPath(libraryInfo);
     if (libraryInfo != null &&
         libraryInfo.category == "Internal") {
       bool allowInternalLibraryAccess = false;
       if (importingLibrary != null) {
         if (importingLibrary.isPlatformLibrary || importingLibrary.isPatch) {
           allowInternalLibraryAccess = true;
         } else if (importingLibrary.canonicalUri.path.contains(
                        'sdk/tests/compiler/dart2js_native')) {
           allowInternalLibraryAccess = true;
         }
@@ skipping 27 matching lines @@
     return libraryRoot.resolve(path);
   }
 
   Uri resolvePatchUri(String dartLibraryPath) {
     String patchPath = lookupPatchPath(dartLibraryPath);
     if (patchPath == null) return null;
     return libraryRoot.resolve(patchPath);
   }
 
   Uri translatePackageUri(leg.Spannable node, Uri uri) {
-    return packageRoot.resolve(uri.path);
+    try {
+      checkValidPackageUri(uri);
+    } on ArgumentError catch (e) {
+      reportError(
+          node,
+          leg.MessageKind.INVALID_PACKAGE_URI,
+          {'uri': uri, 'exception': e.message});
+      return null;
+    }
+    return packages.resolve(uri,
+        notFound: (Uri notFound) {
+          reportError(
+              node,
+              leg.MessageKind.LIBRARY_NOT_FOUND,
+              {'resolvedUri': uri}
+          );
+          return null;
+        });
   }
 
-  Future<bool> run(Uri uri) {
+  Future setupPackages(Uri uri) async {
+    if (packageRoot != null) {
+      // Use "non-file" packages because the file version requires a [Directory]
+      // and we can't depend on 'dart:io' classes.
+      packages = new NonFilePackagesDirectoryPackages(packageRoot);
+    } else if (packageConfig != null) {
+      var packageConfigContents = await provider(packageConfig);
+      if (packageConfigContents is String) {
+        packageConfigContents = UTF8.encode(packageConfigContents);
+      }
+      packages =
+          new MapPackages(pkgs.parse(packageConfigContents, packageConfig));
+    } else {
+      if (packagesDiscoveryProvider == null) {
+        packages = Packages.noPackages;
+      } else {
+        packages = await callUserPackagesDiscovery(uri);
+      }
+    }
+  }
+
+  Future<bool> run(Uri uri) async {
     log('Allowed library categories: $allowedLibraryCategories');
-    return super.run(uri).then((bool success) {
-      int cumulated = 0;
-      for (final task in tasks) {
-        int elapsed = task.timing;
-        if (elapsed != 0) {
-          cumulated += elapsed;
-          log('${task.name} took ${elapsed}msec');
-        }
+
+    await setupPackages(uri);
+    assert(packages != null);
+
+    bool success = await super.run(uri);
+    int cumulated = 0;
+    for (final task in tasks) {
+      int elapsed = task.timing;
+      if (elapsed != 0) {
+        cumulated += elapsed;
+        log('${task.name} took ${elapsed}msec');
       }
-      int total = totalCompileTime.elapsedMilliseconds;
-      log('Total compile-time ${total}msec;'
-          ' unaccounted ${total - cumulated}msec');
-      return success;
-    });
+    }
+    int total = totalCompileTime.elapsedMilliseconds;
+    log('Total compile-time ${total}msec;'
+        ' unaccounted ${total - cumulated}msec');
+    return success;
   }
 
   void reportDiagnostic(leg.Spannable node,
                         leg.Message message,
                         api.Diagnostic kind) {
     leg.SourceSpan span = spanFromSpannable(node);
     if (identical(kind, api.Diagnostic.ERROR)
         || identical(kind, api.Diagnostic.CRASH)
         || (fatalWarnings && identical(kind, api.Diagnostic.WARNING))) {
       compilationFailed = true;
     }
     // [:span.uri:] might be [:null:] in case of a [Script] with no [uri]. For
     // instance in the [Types] constructor in typechecker.dart.
     if (span == null || span.uri == null) {
       callUserHandler(null, null, null, '$message', kind);
     } else {
-      callUserHandler(
-          translateUri(null, span.uri), span.begin, span.end, '$message', kind);
+      callUserHandler(span.uri, span.begin, span.end, '$message', kind);
     }
   }
 
   bool get isMockCompilation {
     return mockableLibraryUsed
       && (options.indexOf('--allow-mock-compilation') != -1);
   }
 
   void callUserHandler(Uri uri, int begin, int end,
                        String message, api.Diagnostic kind) {
@@ skipping 10 matching lines @@
 
   Future callUserProvider(Uri uri) {
     try {
       return userProviderTask.measure(() => provider(uri));
     } catch (ex, s) {
       diagnoseCrashInUserCode('Uncaught exception in input provider', ex, s);
       rethrow;
     }
   }
 
+  Future<Packages> callUserPackagesDiscovery(Uri uri) {
+    try {
+      return userPackagesDiscoveryTask.measure(
+                 () => packagesDiscoveryProvider(uri));
+    } catch (ex, s) {
+      diagnoseCrashInUserCode('Uncaught exception in package discovery', ex, s);
+      rethrow;
+    }
+  }
+
   void diagnoseCrashInUserCode(String message, exception, stackTrace) {
     hasCrashed = true;
     print('$message: ${tryToString(exception)}');
     print(tryToString(stackTrace));
   }
 
   fromEnvironment(String name) => environment[name];
 
   LibraryInfo lookupLibraryInfo(String libraryName) {
     return library_info.LIBRARIES[libraryName];
   }
 }