Stub implementation of patch invariants for the patch refactoring.

lib/compiler/implementation/universe/universe.dart

Index: lib/compiler/implementation/universe/universe.dart
diff --git a/lib/compiler/implementation/universe/universe.dart b/lib/compiler/implementation/universe/universe.dart
index e57d68c0972654edb7fdb6c9cc73178b2aecacc4..d9a86a6e08e074ed5453fd680eec60b7057e113d 100644
--- a/lib/compiler/implementation/universe/universe.dart
+++ b/lib/compiler/implementation/universe/universe.dart
@@ -18,9 +18,13 @@
 #source('selector_map.dart');
 
 class Universe {
+  /// Invariant: Key elements are declaration elements.
   Map<Element, CodeBuffer> generatedCode;
+  /// Invariant: Key elements are declaration elements.
   Map<Element, CodeBuffer> generatedBailoutCode;
+  /// Invariant: Elements are declaration elements.
   final Set<ClassElement> instantiatedClasses;
+  /// Invariant: Elements are declaration elements.
   final Set<FunctionElement> staticFunctionsNeedingGetter;
   final Map<SourceString, Set<Selector>> invokedNames;
   final Map<SourceString, Set<Selector>> invokedGetters;
@@ -29,6 +33,7 @@ class Universe {
   final Map<SourceString, Set<Selector>> fieldSetters;
   final Set<DartType> isChecks;
   // TODO(karlklose): move this data to RuntimeTypeInformation.
+  // Invariant: Elements are declarations.
   Set<Element> checkedClasses;
   final RuntimeTypeInformation rti;
 
@@ -52,10 +57,12 @@ class Universe {
   }
 
   void addGeneratedCode(WorkItem work, CodeBuffer codeBuffer) {
+    assert(work.element.isDeclaration);
     generatedCode[work.element] = codeBuffer;
   }
 
   void addBailoutCode(WorkItem work, CodeBuffer codeBuffer) {
+    assert(work.element.isDeclaration);
     generatedBailoutCode[work.element] = codeBuffer;
   }
 
@@ -293,6 +300,7 @@ class Selector implements Hashable {
                                             compileArgument(Node argument),
                                             compileConstant(Element element),
                                             Compiler compiler) {
+    assert(element.isImplementation);

[ngeoffray, 2012/09/17 12:46:24]

No sure you need this restriction.

[Johnni Winther, 2012/09/20 08:12:23]

The only call-site enforces the invariant so I'll keep it here.

     // If there are named arguments, provide them in the order
     // expected by the called function, which is the source order.
     FunctionSignature parameters = element.computeSignature(compiler);
@@ -340,6 +348,8 @@ class Selector implements Hashable {
   /**
    * Returns [:true:] if the selector and the [element] match; [:false:]
    * otherwise.
+   *
+   * Invariant: [element] must be the implementation element.
    */
   bool addArgumentsToList(Link<Node> arguments,
                           List list,
@@ -347,6 +357,7 @@ class Selector implements Hashable {
                           compileArgument(Node argument),
                           compileConstant(Element element),
                           Compiler compiler) {
+    assert(element.isImplementation);

[ngeoffray, 2012/09/17 12:46:24]

ditto

[Johnni Winther, 2012/09/20 08:12:23]

The call-sites enforces the invariant so I'll keep it here.

     if (!this.applies(element, compiler)) return false;
 
     FunctionSignature parameters = element.computeSignature(compiler);