Include source in kernel.

pkg/kernel/lib/ast.dart

 // Copyright (c) 2016, 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.
 
 /// -----------------------------------------------------------------------
 ///                           ERROR HANDLING
 /// -----------------------------------------------------------------------
 ///
 /// As a rule of thumb, errors that can be detected statically are handled by
 /// the frontend, typically by translating the erroneous code into a 'throw' or
@@ skipping 3486 matching lines @@
 }
 
 // ------------------------------------------------------------------------
 //                                PROGRAM
 // ------------------------------------------------------------------------
 
 /// A way to bundle up all the libraries in a program.
 class Program extends TreeNode {
   final List<Library> libraries;
 
-  /// Map from a source file uri to a line-starts table.
+  /// Map from a source file uri to a line-starts table and source code.
   /// Given a source file uri and a offset in that file one can translate
   /// it to a line:column position in that file.
-  final Map<String, List<int>> uriToLineStarts;
+  final Map<String, LineStartsAndSource> uriToLineStartsAndSource;
 
   /// Reference to the main method in one of the libraries.
   Procedure mainMethod;
 
-  Program([List<Library> libraries, Map<String, List<int>> uriToLineStarts])
+  Program(
+      [List<Library> libraries,
+      Map<String, LineStartsAndSource> uriToLineStartsAndSource])
       : libraries = libraries ?? <Library>[],
-        uriToLineStarts = uriToLineStarts ?? {} {
+        uriToLineStartsAndSource = uriToLineStartsAndSource ?? {} {

[Kevin Millikin (Google), 2016/12/20 12:03:33]

Should be <String, LineStartsAndSource>{}.

Can't we just use

this.uriToLineStartsAndSource = const <String, LineStartsAndSource>{}

in the parameter list?

[jensj, 2016/12/20 13:30:22]

In loader.dart we add to it. We only have it up-front when loading from a dill
file.

     setParents(libraries, this);
   }
 
   accept(TreeVisitor v) => v.visitProgram(this);
 
   visitChildren(Visitor v) {
     visitList(libraries, v);
     mainMethod?.acceptReference(v);
   }
 
   transformChildren(Transformer v) {
     transformList(libraries, v, this);
   }
 
   Program get enclosingProgram => this;
 
   /// Translates an offset to line and column numbers in the given file.
   Location getLocation(String file, int offset) {
-    List<int> lines = uriToLineStarts[file];
+    List<int> lines = uriToLineStartsAndSource[file].lineStarts;
     int low = 0, high = lines.length - 1;
     while (low < high) {
       int mid = high - ((high - low) >> 1); // Get middle, rounding up.
       int pivot = lines[mid];
       if (pivot <= offset) {
         low = mid;
       } else {
         high = mid - 1;
       }
     }
@@ skipping 97 matching lines @@
 
   @override
   defaultTreeNode(TreeNode node) {
     if (node == child) {
       return replacement;
     } else {
       return node;
     }
   }
 }
+
+class LineStartsAndSource {

[Kevin Millikin (Google), 2016/12/20 12:03:33]

I would just call this "Source", not describe the implementation in the name.

It's a bad smell that we have to update so many identifier names just to add a
field to an object.

It doesn't scale anyway, eventually we'll have class
LineStartsAndSourceAndCompressionSchemeAndBreakpointPositionsAnd....

[jensj, 2016/12/20 13:30:22]

Done.

+  final List<int> lineStarts;
+  final String source;
+
+  LineStartsAndSource(this.lineStarts, this.source);
+}