Throw an exception when invalid source file location is encountered.

lib/compiler/implementation/ssa/builder.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.
 
 class Interceptors {
   Compiler compiler;
   Interceptors(Compiler this.compiler);
 
   SourceString mapOperatorToMethodName(Operator op) {
     String name = op.source.stringValue;
@@ skipping 1441 matching lines @@
           value,
           compiler.boolClass,
           kind: HTypeConversion.BOOLEAN_CONVERSION_CHECK);
     }
     HInstruction result = new HBoolify(value);
     add(result);
     return result;
   }
 
   HInstruction attachPosition(HInstruction target, Node node) {
-    target.sourcePosition = sourceFileLocationForToken(node.getBeginToken());
+    target.sourcePosition = sourceFileLocationForBeginToken(node);
     return target;
   }
 
-  SourceFileLocation sourceFileLocationForToken(Token token) {
+  SourceFileLocation sourceFileLocationForBeginToken(Node node) =>
+      sourceFileLocationForToken(node, node.getBeginToken());
+
+  SourceFileLocation sourceFileLocationForEndToken(Node node) =>
+      sourceFileLocationForToken(node, node.getEndToken());
+
+  SourceFileLocation sourceFileLocationForToken(Node node, Token token) {
     Element element = sourceElementStack.last();
     // TODO(johnniwinther): remove the 'element.patch' hack.
     if (element is FunctionElement) {
       FunctionElement functionElement = element;
       if (functionElement.patch != null) element = functionElement.patch;
     }
-    SourceFile sourceFile = element.getCompilationUnit().script.file;
-    return new SourceFileLocation(sourceFile, token);
-  }
+    Script script = element.getCompilationUnit().script;
+    SourceFile sourceFile = script.file;
+    SourceFileLocation location = new SourceFileLocation(sourceFile, token);
+    if (!location.isValid()) {
+      throw MessageKind.INVALID_SOURCE_FILE_LOCATION.message(
+          [token.charOffset, sourceFile.filename, sourceFile.text.length]);
+    }
+    return location;
+}
 
   void visit(Node node) {
     if (node !== null) node.accept(this);
   }
 
   visitBlock(Block node) {
     for (Link<Node> link = node.statements.nodes;
          !link.isEmpty();
          link = link.tail) {
       visit(link.head);
@@ skipping 179 matching lines @@
     endLoop(conditionBlock, conditionExitBlock, jumpHandler, savedLocals);
     HLoopBlockInformation info =
         new HLoopBlockInformation(
             HLoopBlockInformation.loopType(loop),
             wrapExpressionGraph(initializerGraph),
             wrapExpressionGraph(conditionExpression),
             wrapStatementGraph(bodyGraph),
             wrapExpressionGraph(updateGraph),
             conditionBlock.loopInformation.target,
             conditionBlock.loopInformation.labels,
-            sourceFileLocationForToken(loop.getBeginToken()),
-            sourceFileLocationForToken(loop.getEndToken()));
+            sourceFileLocationForBeginToken(loop),
+            sourceFileLocationForEndToken(loop));
 
     startBlock.setBlockFlow(info, current);
     loopInfo.loopBlockInformation = info;
   }
 
   visitFor(For node) {
     assert(node.body !== null);
     void buildInitializer() {
       if (node.initializer === null) return;
       Node initializer = node.initializer;
@@ skipping 107 matching lines @@
 
     HLoopBlockInformation loopBlockInfo =
         new HLoopBlockInformation(
             HLoopBlockInformation.DO_WHILE_LOOP,
             null,
             wrapExpressionGraph(conditionExpression),
             wrapStatementGraph(bodyGraph),
             null,
             loopEntryBlock.loopInformation.target,
             loopEntryBlock.loopInformation.labels,
-            sourceFileLocationForToken(node.getBeginToken()),
-            sourceFileLocationForToken(node.getEndToken()));
+            sourceFileLocationForBeginToken(node),
+            sourceFileLocationForEndToken(node));
     loopEntryBlock.setBlockFlow(loopBlockInfo, current);
     loopInfo.loopBlockInformation = loopBlockInfo;
   }
 
   visitFunctionExpression(FunctionExpression node) {
     ClosureClassMap nestedClosureData =
         compiler.closureToClassMapper.getMappingForNestedFunction(node);
     assert(nestedClosureData !== null);
     assert(nestedClosureData.closureClassElement !== null);
     ClassElement closureClassElement =
@@ skipping 2387 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }