Adding visitors to regurgitate expression types or reset them.

test/cctest/expression-type-collector.h

Index: test/cctest/expression-type-collector.h
diff --git a/test/cctest/expression-type-collector.h b/test/cctest/expression-type-collector.h
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index 0000000000000000000000000000000000000000..cab55e8a7c3a06015cdb4046cf501a4e05afb748
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+++ b/test/cctest/expression-type-collector.h
@@ -0,0 +1,81 @@
+// Copyright 2015 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef V8_EXPRESSION_TYPE_COLLECTOR_H_
+#define V8_EXPRESSION_TYPE_COLLECTOR_H_
+
+#include "src/ast-expression-visitor.h"
+
+namespace v8 {
+namespace internal {
+
+// Macros to define checking of a tree walk.

[rossberg, 2015/08/20 16:34:27]

That's some fancy macro fu there! :)

[bradn, 2015/08/20 21:35:47]

Not sure whether that's a compliment of an insult :-)
Too much, or ok?

[rossberg, 2015/08/21 12:36:51]

Can't make up my mind. :) I think it's fine and useful for tests, but perhaps
would be too much in "real" code.

+// Assumes:
+//   * type walk result in "types"
+//   * HandlesAndZoneScope in "handles"
+//
+// Usage:
+// CHECK_TYPES_BEGIN {
+//   CHECK_EXPR(Assignment, OTHER) {
+//     CHECK_VAR(a, OTHER);
+//     CHECK_VAR(b, OTHER);
+//   }
+// } CHECK_TYPES_END
+
+#define CHECK_TYPES_BEGIN \
+  {                       \
+    size_t index = 0;     \
+    int depth = 0;
+
+#define CHECK_TYPES_END          \
+  CHECK_EQ(index, types.size()); \
+  }
+
+#define DEFAULT_TYPE Bounds::Unbounded(handles.main_zone())
+#define INT32_TYPE                            \
+  Bounds(Type::Signed32(handles.main_zone()), \
+         Type::Signed32(handles.main_zone()))
+
+#define CHECK_EXPR(ekind, type)                     \
+  CHECK_LT(index, types.size());                    \
+  CHECK(strcmp(#ekind, types[index].kind) == 0);    \
+  CHECK_EQ(depth, types[index].depth);              \
+  CHECK(type.lower->Is(types[index].bounds.lower)); \
+  CHECK(type.upper->Is(types[index].bounds.upper)); \
+  for (int j = (++depth, ++index, 0); j < 1 ? 1 : (--depth, 0); ++j)
+
+#define CHECK_VAR(vname, type)                                     \
+  CHECK_EXPR(VariableProxy, type);                                 \
+  CHECK_EQ(#vname, std::string(types[index - 1].name->raw_data(),  \
+                               types[index - 1].name->raw_data() + \
+                                   types[index - 1].name->byte_length()));
+
+// A Visitor over a CompilationInfo's AST that collects
+// a human readable string summarizing structure and types.
+// Used for testing of the typing information attached to the
+// expression nodes of an AST.
+
+struct ExpressionTypeEntry {
+  int depth;
+  const char* kind;
+  const AstRawString* name;
+  Bounds bounds;
+};
+
+class ExpressionTypeCollector : public AstExpressionVisitor {
+ public:
+  static void Run(CompilationInfo* info, ZoneVector<ExpressionTypeEntry>* dst);
+
+ protected:
+  void VisitExpression(Expression* expression);
+
+ private:
+  explicit ExpressionTypeCollector(CompilationInfo* info);
+
+  ZoneVector<ExpressionTypeEntry>* result_;
+};
+}
+}  // namespace v8::internal
+
+#endif  // V8_EXPRESSION_TYPE_COLLECTOR_H_