[wasm] Also test structured stack trace

test/mjsunit/wasm/stack.js

Index: test/mjsunit/wasm/stack.js
diff --git a/test/mjsunit/wasm/stack.js b/test/mjsunit/wasm/stack.js
index ed05517ae5070bb1361c5f23ef3c3618beed7114..11f5f84703698f908c0df9909434ce94215cccb7 100644
--- a/test/mjsunit/wasm/stack.js
+++ b/test/mjsunit/wasm/stack.js
@@ -2,39 +2,75 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// clang-format off
 // Flags: --expose-wasm
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");
 
-var expected = "Error\n" +
-    // The line numbers below will change as this test gains / loses lines..
-    "    at STACK (stack.js:24:11)\n" +     // --
-    "    at <WASM> (<anonymous>)\n" +       // TODO(jfb): wasm stack here.
-    "    at testStack (stack.js:38:18)\n" + // --
-    "    at stack.js:40:3";                 // --
-
 // The stack trace contains file path, only keep "stack.js".
 function stripPath(s) {
   return s.replace(/[^ (]*stack\.js/g, "stack.js");
 }
 
+function verifyStack(frames, expected) {
+  assertEquals(expected.length, frames.length, "number of frames mismatch");
+  expected.forEach(function(exp, i) {
+    assertEquals(exp[0], frames[i].getFunctionName(),
+        "["+i+"].getFunctionName()");
+    assertEquals(exp[1], frames[i].getLineNumber(),
+        "["+i+"].getLineNumber()");
+    assertContains(exp[2], frames[i].getFileName(),
+        "["+i+"].getFileName()");
+    assertContains(exp[3], frames[i].toString(),
+        "["+i+"].toString()");
+  });
+}
+
+
 var stack;
 function STACK() {
   var e = new Error();
   stack = e.stack;
 }
 
-(function testStack() {
-  var builder = new WasmModuleBuilder();
+var builder = new WasmModuleBuilder();
+
+builder.addImport("func", [kAstStmt]);
 
-  builder.addImport("func", [kAstStmt]);
+builder.addFunction("main", [kAstStmt])
+  .addBody([kExprCallImport, 0])
+  .exportAs("main");
 
-  builder.addFunction(undefined, [kAstStmt])
-    .addBody([kExprCallImport, 0])
-    .exportAs("main");
+var module = builder.instantiate({func: STACK});
 
-  var module = builder.instantiate({func: STACK});
+(function testSimpleStack() {
+  var expected_string = "Error\n" +
+    // The line numbers below will change as this test gains / loses lines..
+    "    at STACK (stack.js:33:11)\n" +           // --
+    "    at <WASM> (<anonymous>)\n" +             // TODO(jfb): wasm stack here.
+    "    at testSimpleStack (stack.js:55:18)\n" + // --
+    "    at stack.js:57:3";                       // --
+
+  module.exports.main();
+  assertEquals(expected_string, stripPath(stack));
+})();
+
+// For the remaining tests, collect the Callsite objects instead of just a
+// string:
+Error.prepareStackTrace = function(error, frames) {
+  return frames;
+};
+
+(function testStackFrames() {
   module.exports.main();
-  assertEquals(expected, stripPath(stack));
+
+  // TODO(clemensh): add a isWasm() method or similar, and test it
+  verifyStack(stack, [
+      //        function   line        file          toString
+      [          "STACK",    33, "stack.js", "stack.js:33:11"],
+      [         "<WASM>",  null,       null,         "<WASM>"],
+      ["testStackFrames",    66, "stack.js", "stack.js:66:18"],
+      [             null,    76, "stack.js",  "stack.js:76:3"]
+  ]);
 })();