Parse the 'patches' argument in SDK libraries declarations.

pkg/analyzer/lib/src/generated/sdk.dart

 // Copyright (c) 2014, 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 analyzer.src.generated.sdk;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
@@ skipping 256 matching lines @@
   String toString() {
     StringBuffer buffer = new StringBuffer();
     bool needsSeparator = false;
     void add(String optionName) {
       if (needsSeparator) {
         buffer.write(', ');
       }
       buffer.write(optionName);
       needsSeparator = true;
     }
+
     for (String path in paths) {
       add(path);
     }
     if (needsSeparator) {
       buffer.write(' ');
     }
     buffer.write('(');
     buffer.write(AnalysisOptionsImpl
         .decodeCrossContextOptions(options.encodeCrossContextOptions()));
     buffer.write(')');
@@ skipping 14 matching lines @@
    */
   static String _IMPLEMENTATION = "implementation";
 
   /**
    * The name of the optional parameter used to specify the path used when
    * compiling for dart2js.
    */
   static String _DART2JS_PATH = "dart2jsPath";
 
   /**
+   * The name of the `dart2js` platform.
+   */
+  static String _DART2JS_PLATFORM = 'DART2JS_PLATFORM';
+
+  /**
    * The name of the optional parameter used to indicate whether the library is
    * documented.
    */
   static String _DOCUMENTED = "documented";
 
   /**
    * The name of the optional parameter used to specify the category of the
    * library.
    */
   static String _CATEGORIES = "categories";
 
   /**
+   * The name of the optional parameter used to specify the patches for
+   * the library.
+   */
+  static String _PATCHES = "patches";
+
+  /**
    * The name of the optional parameter used to specify the platforms on which
    * the library can be used.
    */
   static String _PLATFORMS = "platforms";
 
   /**
    * The value of the [PLATFORMS] parameter used to specify that the library can
    * be used on the VM.
    */
   static String _VM_PLATFORM = "VM_PLATFORM";
@@ skipping 57 matching lines @@
         } else if (argument is NamedExpression) {
           String name = argument.name.label.name;
           Expression expression = argument.expression;
           if (name == _CATEGORIES) {
             library.category =
                 convertCategories((expression as StringLiteral).stringValue);
           } else if (name == _IMPLEMENTATION) {
             library._implementation = (expression as BooleanLiteral).value;
           } else if (name == _DOCUMENTED) {
             library.documented = (expression as BooleanLiteral).value;
+          } else if (name == _PATCHES) {
+            if (expression is MapLiteral) {
+              expression.entries.forEach((MapLiteralEntry entry) {
+                Expression key = entry.key;
+                Expression value = entry.value;
+                if (key is SimpleIdentifier && value is SimpleStringLiteral) {

[Paul Berry, 2016/10/10 19:14:38]

Two issues:

1. The "patches" parameter should be a Map<int, List<String>>, where the list is
a list of paths to patch files.  (This is necessary to accommodate the VM, which
has multiple patches per library).  This code is treating it as a Map<int,
String>.

2. In the long term we'll need to accept keys of the form `PLATFORM1 | PLATFORM2
| PLATFORM3` (so that we can share most patch files between Dart2js and DDC). 
If you just want to add a TODO comment for now, that's fine with me.

[scheglov, 2016/10/10 19:41:52]

OK, I see now.
The key of this map must be a combination of platforms.
Done.

+                  int platform = _convertPlatform(key.name);
+                  library.addPatch(platform, value.value);
+                }
+              });
+            }
           } else if (name == _PLATFORMS) {
             if (expression is SimpleIdentifier) {
               String identifier = expression.name;
               if (identifier == _VM_PLATFORM) {
                 library.setVmLibrary();
               } else {
                 library.setDart2JsLibrary();
               }
             }
           } else if (_useDart2jsPaths && name == _DART2JS_PATH) {
             if (expression is SimpleStringLiteral) {
               library.path = expression.value;
             }
           }
         }
       }
       _librariesMap.setLibrary(libraryName, library);
     }
     return null;
   }
+
+  /**
+   * Return the platform constant value for the [name].  Throw [ArgumentError]
+   * if the given [name] is not a valid platform name.
+   */
+  static int _convertPlatform(String name) {
+    if (name == _DART2JS_PLATFORM) {
+      return SdkLibraryImpl.DART2JS_PLATFORM;
+    }
+    if (name == _VM_PLATFORM) {
+      return SdkLibraryImpl.VM_PLATFORM;
+    }
+    throw new ArgumentError('Invalid platform name: $name');
+  }
 }
 
 /**
  * Represents a single library in the SDK
  */
 abstract class SdkLibrary {
   /**
    * Return the name of the category containing the library.
    */
   String get category;
@@ skipping 32 matching lines @@
    * Return the path to the file defining the library. The path is relative to
    * the `lib` directory within the SDK.
    */
   String get path;
 
   /**
    * Return the short name of the library. This is the URI of the library,
    * including `dart:`.
    */
   String get shortName;
+
+  /**
+   * Return the list of paths to the patch files that should be applied
+   * to this library for the given [platform], not `null`.
+   */
+  List<String> getPatches(int platform);
 }
 
 /**
  * The information known about a single library within the SDK.
  */
 class SdkLibraryImpl implements SdkLibrary {
   /**
    * The bit mask used to access the bit representing the flag indicating
    * whether a library is intended to work on the dart2js platform.
    */
@@ skipping 32 matching lines @@
    * A flag indicating whether the library is an implementation library.
    */
   bool _implementation = false;
 
   /**
    * An encoding of which platforms this library is intended to work on.
    */
   int _platforms = 0;
 
   /**
+   * The mapping from the platform to the list of patches that should be
+   * applied for this library.
+   */
+  final Map<int, List<String>> _patches = new HashMap<int, List<String>>();
+
+  /**
    * Initialize a newly created library to represent the library with the given
    * [name].
    */
   SdkLibraryImpl(this.shortName);
 
   /**
    * Set whether the library is documented.
    */
   void set documented(bool documented) {
     this._documented = documented;
@@ skipping 11 matching lines @@
   @override
   bool get isInternal => category == "Internal";
 
   @override
   bool get isShared => category == "Shared";
 
   @override
   bool get isVmLibrary => (_platforms & VM_PLATFORM) != 0;
 
   /**
+   * Add a new patch with the given [path] that should be applied for the
+   * given [platform].
+   */
+  void addPatch(int platform, String path) {
+    assert(path != null);
+    _patches.putIfAbsent(platform, () => <String>[]).add(path);
+  }
+
+  @override
+  List<String> getPatches(int platform) {
+    return _patches[platform] ?? const <String>[];
+  }
+
+  /**
    * Record that this library can be compiled to JavaScript by dart2js.
    */
   void setDart2JsLibrary() {
     _platforms |= DART2JS_PLATFORM;
   }
 
   /**
    * Record that this library can be run on the VM.
    */
   void setVmLibrary() {
     _platforms |= VM_PLATFORM;
   }
 }