14 files changed, 199 insertions, 79 deletions
diff --git a/test/gen-spec-js.py b/test/gen-spec-js.py
index 5e8d65ca..3937afad 100755
--- a/test/gen-spec-js.py
+++ b/test/gen-spec-js.py
@@ -378,15 +378,20 @@ class ModuleExtender(object):
 
 class JSWriter(object):
 
-  def __init__(self, base_dir, commands, out_file):
+  def __init__(self, base_dir, spec_json, out_file):
     self.base_dir = base_dir
-    self.commands = commands
+    self.source_filename = os.path.basename(spec_json['source_filename'])
+    self.commands = spec_json['commands']
     self.out_file = out_file
+    self.module_idx = 0
 
   def Write(self):
     for command in self.commands:
       self._WriteCommand(command)
 
+  def _WriteFileAndLine(self, command):
+    self.out_file.write('// %s:%d\n' % (self.source_filename, command['line']))
+
   def _WriteCommand(self, command):
     command_funcs = {
         'module': self._WriteModuleCommand,
@@ -406,20 +411,28 @@ class JSWriter(object):
     func = command_funcs.get(command['type'])
     if func is None:
       raise Error('Unexpected type: %s' % command['type'])
+    self._WriteFileAndLine(command)
     func(command)
+    self.out_file.write('\n')
+
+  def _ModuleIdxName(self):
+    return '$%d' % self.module_idx
 
   def _WriteModuleCommand(self, command):
+    self.module_idx += 1
+    idx_name = self._ModuleIdxName()
+
+    self.out_file.write('let %s = instance("%s");\n' %
+                        (idx_name, self._Module(command['filename'])))
     if 'name' in command:
-      self.out_file.write('let %s = ' % command['name'])
-    self.out_file.write('$$ = instance("%s");\n' %
-                        self._Module(command['filename']))
+      self.out_file.write('let %s = %s;\n' % (command['name'], idx_name))
 
   def _WriteActionCommand(self, command):
     self.out_file.write('%s;\n' % self._Action(command['action']))
 
   def _WriteRegisterCommand(self, command):
-    self.out_file.write('register("%s", %s)\n' % (command['as'],
-                                                  command.get('name', '$$')))
+    self.out_file.write('register("%s", %s)\n' % (
+      command['as'], command.get('name', self._ModuleIdxName())))
 
   def _WriteAssertModuleCommand(self, command):
     # Don't bother writing out text modules; they can't be parsed by JS.
@@ -464,15 +477,15 @@ class JSWriter(object):
 
   def _Action(self, action):
     type_ = action['type']
-    if type_ not in ('invoke', 'get'):
-      raise Error('Unexpected action type: %s' % type_)
-
-    args = ''
+    module = action.get('module', self._ModuleIdxName())
+    field = EscapeJSString(action['field'])
     if type_ == 'invoke':
-      args = '(%s)' % self._ConstantList(action.get('args', []))
-
-    return '%s.exports["%s"]%s' % (action.get('module', '$$'),
-                                   EscapeJSString(action['field']), args)
+      args = '[%s]' % self._ConstantList(action.get('args', []))
+      return 'call(%s, "%s", %s)' % (module, field, args)
+    elif type_ == 'get':
+      return 'get(%s, "%s")' % (module, field)
+    else:
+      raise Error('Unexpected action type: %s' % type_)
 
 
 def main(args):
@@ -529,7 +542,7 @@ def main(args):
         output.write(prefix_file.read())
         output.write('\n')
 
-    JSWriter(json_dir, all_commands, output).Write()
+    JSWriter(json_dir, spec_json, output).Write()
 
   if options.output:
     out_file = open(options.output, 'w')
diff --git a/test/gen-spec-js/action.txt b/test/gen-spec-js/action.txt
index b2669cdf..ed26e5ef 100644
--- a/test/gen-spec-js/action.txt
+++ b/test/gen-spec-js/action.txt
@@ -11,7 +11,13 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x01\x7f\x00\x02\x12\x01\x08\x73\x70\x65\x63\x74\x65\x73\x74\x05\x70\x72\x69\x6e\x74\x00\x00\x03\x02\x01\x00\x06\x06\x01\x7f\x00\x41\x0e\x0b\x07\x16\x02\x09\x70\x72\x69\x6e\x74\x5f\x69\x33\x32\x00\x01\x06\x67\x6c\x6f\x62\x61\x6c\x03\x00\x0a\x08\x01\x06\x00\x20\x00\x10\x00\x0b");
-$$.exports["print_i32"](1);
-$$.exports["global"];
+// action.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x01\x7f\x00\x02\x12\x01\x08\x73\x70\x65\x63\x74\x65\x73\x74\x05\x70\x72\x69\x6e\x74\x00\x00\x03\x02\x01\x00\x06\x06\x01\x7f\x00\x41\x0e\x0b\x07\x16\x02\x09\x70\x72\x69\x6e\x74\x5f\x69\x33\x32\x00\x01\x06\x67\x6c\x6f\x62\x61\x6c\x03\x00\x0a\x08\x01\x06\x00\x20\x00\x10\x00\x0b");
+
+// action.txt:9
+call($1, "print_i32", [1]);
+
+// action.txt:10
+get($1, "global");
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_exhaustion.txt b/test/gen-spec-js/assert_exhaustion.txt
index 51ba3918..7fa1e718 100644
--- a/test/gen-spec-js/assert_exhaustion.txt
+++ b/test/gen-spec-js/assert_exhaustion.txt
@@ -8,6 +8,10 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x04\x01\x60\x00\x00\x03\x02\x01\x00\x07\x07\x01\x03\x66\x6f\x6f\x00\x00\x0a\x06\x01\x04\x00\x10\x00\x0b");
-assert_exhaustion(() => $$.exports["foo"]());
+// assert_exhaustion.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x04\x01\x60\x00\x00\x03\x02\x01\x00\x07\x07\x01\x03\x66\x6f\x6f\x00\x00\x0a\x06\x01\x04\x00\x10\x00\x0b");
+
+// assert_exhaustion.txt:7
+assert_exhaustion(() => call($1, "foo", []));
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_malformed-quote.txt b/test/gen-spec-js/assert_malformed-quote.txt
index 57456a49..a842e29f 100644
--- a/test/gen-spec-js/assert_malformed-quote.txt
+++ b/test/gen-spec-js/assert_malformed-quote.txt
@@ -8,4 +8,6 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
+// assert_malformed-quote.txt:6
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_malformed.txt b/test/gen-spec-js/assert_malformed.txt
index e72e8ba2..1eb45521 100644
--- a/test/gen-spec-js/assert_malformed.txt
+++ b/test/gen-spec-js/assert_malformed.txt
@@ -6,5 +6,7 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
+// assert_malformed.txt:4
 assert_malformed("\x00\x61\x73\x6d\xbc\x0a\x00\x00");
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_return.txt b/test/gen-spec-js/assert_return.txt
index 54b86416..7c65f340 100644
--- a/test/gen-spec-js/assert_return.txt
+++ b/test/gen-spec-js/assert_return.txt
@@ -37,12 +37,28 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x24\x07\x60\x00\x00\x60\x00\x01\x7f\x60\x02\x7f\x7f\x01\x7f\x60\x02\x7e\x7e\x01\x7e\x60\x02\x7d\x7d\x01\x7d\x60\x02\x7c\x7c\x01\x7c\x60\x00\x01\x7d\x03\x0a\x09\x00\x01\x02\x03\x04\x05\x06\x00\x00\x07\x56\x09\x09\x6e\x6f\x5f\x72\x65\x73\x75\x6c\x74\x00\x00\x02\x34\x32\x00\x01\x07\x69\x33\x32\x2e\x61\x64\x64\x00\x02\x07\x69\x36\x34\x2e\x61\x64\x64\x00\x03\x07\x66\x33\x32\x2e\x61\x64\x64\x00\x04\x07\x66\x36\x34\x2e\x61\x64\x64\x00\x05\x03\x6e\x61\x6e\x00\x06\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x07\x08\x61\x73\x73\x65\x72\x74\x5f\x31\x00\x08\x0a\x5a\x09\x02\x00\x0b\x04\x00\x41\x2a\x0b\x07\x00\x20\x00\x20\x01\x6a\x0b\x07\x00\x20\x00\x20\x01\x7c\x0b\x07\x00\x20\x00\x20\x01\x92\x0b\x07\x00\x20\x00\x20\x01\xa0\x0b\x07\x00\x43\x02\x00\x80\x7f\x0b\x13\x00\x02\x40\x42\x01\x42\x02\x10\x03\x42\x03\x51\x45\x0d\x00\x0f\x0b\x00\x0b\x14\x00\x02\x40\x10\x06\xbc\x43\x02\x00\x80\x7f\xbc\x46\x45\x0d\x00\x0f\x0b\x00\x0b");
-assert_return(() => $$.exports["no_result"]());
-assert_return(() => $$.exports["42"](), 42);
-assert_return(() => $$.exports["i32.add"](1, 2), 3);
-assert_return(() => $$.exports["assert_0"]());
-assert_return(() => $$.exports["f32.add"](f32(1.0), f32(2.0)), f32(3.0));
-assert_return(() => $$.exports["f64.add"](1.0, 2.0), 3.0);
-assert_return(() => $$.exports["assert_1"]());
+// assert_return.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x24\x07\x60\x00\x00\x60\x00\x01\x7f\x60\x02\x7f\x7f\x01\x7f\x60\x02\x7e\x7e\x01\x7e\x60\x02\x7d\x7d\x01\x7d\x60\x02\x7c\x7c\x01\x7c\x60\x00\x01\x7d\x03\x0a\x09\x00\x01\x02\x03\x04\x05\x06\x00\x00\x07\x56\x09\x09\x6e\x6f\x5f\x72\x65\x73\x75\x6c\x74\x00\x00\x02\x34\x32\x00\x01\x07\x69\x33\x32\x2e\x61\x64\x64\x00\x02\x07\x69\x36\x34\x2e\x61\x64\x64\x00\x03\x07\x66\x33\x32\x2e\x61\x64\x64\x00\x04\x07\x66\x36\x34\x2e\x61\x64\x64\x00\x05\x03\x6e\x61\x6e\x00\x06\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x07\x08\x61\x73\x73\x65\x72\x74\x5f\x31\x00\x08\x0a\x5a\x09\x02\x00\x0b\x04\x00\x41\x2a\x0b\x07\x00\x20\x00\x20\x01\x6a\x0b\x07\x00\x20\x00\x20\x01\x7c\x0b\x07\x00\x20\x00\x20\x01\x92\x0b\x07\x00\x20\x00\x20\x01\xa0\x0b\x07\x00\x43\x02\x00\x80\x7f\x0b\x13\x00\x02\x40\x42\x01\x42\x02\x10\x03\x42\x03\x51\x45\x0d\x00\x0f\x0b\x00\x0b\x14\x00\x02\x40\x10\x06\xbc\x43\x02\x00\x80\x7f\xbc\x46\x45\x0d\x00\x0f\x0b\x00\x0b");
+
+// assert_return.txt:24
+assert_return(() => call($1, "no_result", []));
+
+// assert_return.txt:25
+assert_return(() => call($1, "42", []), 42);
+
+// assert_return.txt:27
+assert_return(() => call($1, "i32.add", [1, 2]), 3);
+
+// assert_return.txt:29
+assert_return(() => call($1, "assert_0", []));
+
+// assert_return.txt:31
+assert_return(() => call($1, "f32.add", [f32(1.0), f32(2.0)]), f32(3.0));
+
+// assert_return.txt:32
+assert_return(() => call($1, "f64.add", [1.0, 2.0]), 3.0);
+
+// assert_return.txt:35
+assert_return(() => call($1, "assert_1", []));
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_return_nan.txt b/test/gen-spec-js/assert_return_nan.txt
index b154c108..bc4cdd95 100644
--- a/test/gen-spec-js/assert_return_nan.txt
+++ b/test/gen-spec-js/assert_return_nan.txt
@@ -23,13 +23,31 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x16\x05\x60\x00\x01\x7d\x60\x01\x7d\x01\x7d\x60\x00\x01\x7c\x60\x01\x7c\x01\x7c\x60\x00\x00\x03\x0b\x0a\x00\x00\x01\x02\x02\x03\x04\x04\x04\x04\x07\x85\x01\x0a\x07\x66\x33\x32\x5f\x6e\x61\x6e\x00\x00\x10\x66\x33\x32\x5f\x6e\x61\x6e\x5f\x77\x69\x74\x68\x5f\x74\x61\x67\x00\x01\x0c\x66\x33\x32\x5f\x70\x61\x73\x73\x74\x68\x72\x75\x00\x02\x07\x66\x36\x34\x5f\x6e\x61\x6e\x00\x03\x10\x66\x36\x34\x5f\x6e\x61\x6e\x5f\x77\x69\x74\x68\x5f\x74\x61\x67\x00\x04\x0c\x66\x36\x34\x5f\x70\x61\x73\x73\x74\x68\x72\x75\x00\x05\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x06\x08\x61\x73\x73\x65\x72\x74\x5f\x31\x00\x07\x08\x61\x73\x73\x65\x72\x74\x5f\x32\x00\x08\x08\x61\x73\x73\x65\x72\x74\x5f\x33\x00\x09\x0a\xd3\x01\x0a\x07\x00\x43\x00\x00\xc0\x7f\x0b\x07\x00\x43\x34\x12\x80\x7f\x0b\x04\x00\x20\x00\x0b\x0b\x00\x44\x00\x00\x00\x00\x00\x00\xf8\x7f\x0b\x0b\x00\x44\x34\x12\x00\x00\x00\x00\xf0\x7f\x0b\x04\x00\x20\x00\x0b\x20\x00\x02\x40\x43\x00\x00\xc0\xff\x10\x02\xbc\x41\xff\xff\xff\xff\x07\x71\x41\x80\x80\x80\xfe\x07\x46\x45\x0d\x00\x0f\x0b\x00\x0b\x20\x00\x02\x40\x43\x34\x12\x80\x7f\x10\x02\xbc\x41\x80\x80\x80\xfe\x07\x71\x41\x80\x80\x80\xfe\x07\x46\x45\x0d\x00\x0f\x0b\x00\x0b\x2e\x00\x02\x40\x44\x00\x00\x00\x00\x00\x00\xf8\xff\x10\x05\xbd\x42\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00\x83\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x51\x45\x0d\x00\x0f\x0b\x00\x0b\x2e\x00\x02\x40\x44\x34\x12\x00\x00\x00\x00\xf0\x7f\x10\x05\xbd\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x83\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x51\x45\x0d\x00\x0f\x0b\x00\x0b");
-assert_return_canonical_nan(() => $$.exports["f32_nan"]());
-assert_return_arithmetic_nan(() => $$.exports["f32_nan_with_tag"]());
-assert_return_canonical_nan(() => $$.exports["f64_nan"]());
-assert_return_arithmetic_nan(() => $$.exports["f64_nan_with_tag"]());
-assert_return(() => $$.exports["assert_0"]());
-assert_return(() => $$.exports["assert_1"]());
-assert_return(() => $$.exports["assert_2"]());
-assert_return(() => $$.exports["assert_3"]());
+// assert_return_nan.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x16\x05\x60\x00\x01\x7d\x60\x01\x7d\x01\x7d\x60\x00\x01\x7c\x60\x01\x7c\x01\x7c\x60\x00\x00\x03\x0b\x0a\x00\x00\x01\x02\x02\x03\x04\x04\x04\x04\x07\x85\x01\x0a\x07\x66\x33\x32\x5f\x6e\x61\x6e\x00\x00\x10\x66\x33\x32\x5f\x6e\x61\x6e\x5f\x77\x69\x74\x68\x5f\x74\x61\x67\x00\x01\x0c\x66\x33\x32\x5f\x70\x61\x73\x73\x74\x68\x72\x75\x00\x02\x07\x66\x36\x34\x5f\x6e\x61\x6e\x00\x03\x10\x66\x36\x34\x5f\x6e\x61\x6e\x5f\x77\x69\x74\x68\x5f\x74\x61\x67\x00\x04\x0c\x66\x36\x34\x5f\x70\x61\x73\x73\x74\x68\x72\x75\x00\x05\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x06\x08\x61\x73\x73\x65\x72\x74\x5f\x31\x00\x07\x08\x61\x73\x73\x65\x72\x74\x5f\x32\x00\x08\x08\x61\x73\x73\x65\x72\x74\x5f\x33\x00\x09\x0a\xd3\x01\x0a\x07\x00\x43\x00\x00\xc0\x7f\x0b\x07\x00\x43\x34\x12\x80\x7f\x0b\x04\x00\x20\x00\x0b\x0b\x00\x44\x00\x00\x00\x00\x00\x00\xf8\x7f\x0b\x0b\x00\x44\x34\x12\x00\x00\x00\x00\xf0\x7f\x0b\x04\x00\x20\x00\x0b\x20\x00\x02\x40\x43\x00\x00\xc0\xff\x10\x02\xbc\x41\xff\xff\xff\xff\x07\x71\x41\x80\x80\x80\xfe\x07\x46\x45\x0d\x00\x0f\x0b\x00\x0b\x20\x00\x02\x40\x43\x34\x12\x80\x7f\x10\x02\xbc\x41\x80\x80\x80\xfe\x07\x71\x41\x80\x80\x80\xfe\x07\x46\x45\x0d\x00\x0f\x0b\x00\x0b\x2e\x00\x02\x40\x44\x00\x00\x00\x00\x00\x00\xf8\xff\x10\x05\xbd\x42\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00\x83\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x51\x45\x0d\x00\x0f\x0b\x00\x0b\x2e\x00\x02\x40\x44\x34\x12\x00\x00\x00\x00\xf0\x7f\x10\x05\xbd\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x83\x42\x80\x80\x80\x80\x80\x80\x80\xfc\xff\x00\x51\x45\x0d\x00\x0f\x0b\x00\x0b");
+
+// assert_return_nan.txt:12
+assert_return_canonical_nan(() => call($1, "f32_nan", []));
+
+// assert_return_nan.txt:13
+assert_return_arithmetic_nan(() => call($1, "f32_nan_with_tag", []));
+
+// assert_return_nan.txt:14
+assert_return_canonical_nan(() => call($1, "f64_nan", []));
+
+// assert_return_nan.txt:15
+assert_return_arithmetic_nan(() => call($1, "f64_nan_with_tag", []));
+
+// assert_return_nan.txt:18
+assert_return(() => call($1, "assert_0", []));
+
+// assert_return_nan.txt:19
+assert_return(() => call($1, "assert_1", []));
+
+// assert_return_nan.txt:20
+assert_return(() => call($1, "assert_2", []));
+
+// assert_return_nan.txt:21
+assert_return(() => call($1, "assert_3", []));
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_trap.txt b/test/gen-spec-js/assert_trap.txt
index 2096245c..cf21ef49 100644
--- a/test/gen-spec-js/assert_trap.txt
+++ b/test/gen-spec-js/assert_trap.txt
@@ -12,7 +12,13 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x09\x02\x60\x00\x00\x60\x01\x7d\x01\x7f\x03\x04\x03\x00\x01\x00\x07\x28\x03\x0b\x75\x6e\x72\x65\x61\x63\x68\x61\x62\x6c\x65\x00\x00\x0b\x69\x33\x32\x2e\x74\x72\x75\x6e\x63\x5f\x73\x00\x01\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x02\x0a\x17\x03\x03\x00\x00\x0b\x05\x00\x20\x00\xa8\x0b\x0b\x00\x43\x00\x00\xc0\xff\x10\x01\x0c\x00\x0b");
-assert_trap(() => $$.exports["unreachable"]());
-assert_trap(() => $$.exports["assert_0"]());
+// assert_trap.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x09\x02\x60\x00\x00\x60\x01\x7d\x01\x7f\x03\x04\x03\x00\x01\x00\x07\x28\x03\x0b\x75\x6e\x72\x65\x61\x63\x68\x61\x62\x6c\x65\x00\x00\x0b\x69\x33\x32\x2e\x74\x72\x75\x6e\x63\x5f\x73\x00\x01\x08\x61\x73\x73\x65\x72\x74\x5f\x30\x00\x02\x0a\x17\x03\x03\x00\x00\x0b\x05\x00\x20\x00\xa8\x0b\x0b\x00\x43\x00\x00\xc0\xff\x10\x01\x0c\x00\x0b");
+
+// assert_trap.txt:9
+assert_trap(() => call($1, "unreachable", []));
+
+// assert_trap.txt:11
+assert_trap(() => call($1, "assert_0", []));
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_uninstantiable.txt b/test/gen-spec-js/assert_uninstantiable.txt
index 84d8c5e6..7f0024c0 100644
--- a/test/gen-spec-js/assert_uninstantiable.txt
+++ b/test/gen-spec-js/assert_uninstantiable.txt
@@ -8,5 +8,7 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
+// assert_uninstantiable.txt:4
 assert_uninstantiable("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x04\x01\x60\x00\x00\x03\x02\x01\x00\x08\x01\x00\x0a\x05\x01\x03\x00\x00\x0b");
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/assert_unlinkable.txt b/test/gen-spec-js/assert_unlinkable.txt
index 8c5f1699..591d222b 100644
--- a/test/gen-spec-js/assert_unlinkable.txt
+++ b/test/gen-spec-js/assert_unlinkable.txt
@@ -6,5 +6,7 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
+// assert_unlinkable.txt:4
 assert_unlinkable("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x04\x01\x60\x00\x00\x02\x0b\x01\x03\x66\x6f\x6f\x03\x62\x61\x72\x00\x00");
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/basic.txt b/test/gen-spec-js/basic.txt
index 57d542f8..d0827ef2 100644
--- a/test/gen-spec-js/basic.txt
+++ b/test/gen-spec-js/basic.txt
@@ -7,6 +7,10 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x06\x01\x02\x34\x32\x00\x00\x0a\x06\x01\x04\x00\x41\x2a\x0b");
-assert_return(() => $$.exports["42"](), 42);
+// basic.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x06\x01\x02\x34\x32\x00\x00\x0a\x06\x01\x04\x00\x41\x2a\x0b");
+
+// basic.txt:6
+assert_return(() => call($1, "42", []), 42);
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/many-modules.txt b/test/gen-spec-js/many-modules.txt
index c6179866..b585636d 100644
--- a/test/gen-spec-js/many-modules.txt
+++ b/test/gen-spec-js/many-modules.txt
@@ -11,11 +11,28 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-let $A = $$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x01\x0b");
-let $B = $$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x02\x0b");
-let $C = $$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x03\x0b");
-assert_return(() => $$.exports["f"](), 3);
-assert_return(() => $A.exports["f"](), 1);
-assert_return(() => $B.exports["f"](), 2);
-assert_return(() => $C.exports["f"](), 3);
+// many-modules.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x01\x0b");
+let $A = $1;
+
+// many-modules.txt:4
+let $2 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x02\x0b");
+let $B = $2;
+
+// many-modules.txt:5
+let $3 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x03\x0b");
+let $C = $3;
+
+// many-modules.txt:7
+assert_return(() => call($3, "f", []), 3);
+
+// many-modules.txt:8
+assert_return(() => call($A, "f", []), 1);
+
+// many-modules.txt:9
+assert_return(() => call($B, "f", []), 2);
+
+// many-modules.txt:10
+assert_return(() => call($C, "f", []), 3);
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-js/register.txt b/test/gen-spec-js/register.txt
index 79c0ebfa..f89a33a6 100644
--- a/test/gen-spec-js/register.txt
+++ b/test/gen-spec-js/register.txt
@@ -13,8 +13,16 @@
 (;; STDOUT ;;;
 // A deliberately empty file for testing.
 
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x01\x0b");
-register("A", $$)
-$$ = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x02\x07\x01\x01\x41\x01\x66\x00\x00\x03\x02\x01\x00\x07\x05\x01\x01\x67\x00\x01\x0a\x06\x01\x04\x00\x10\x00\x0b");
-assert_return(() => $$.exports["g"](), 1);
+// register.txt:3
+let $1 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x03\x02\x01\x00\x07\x05\x01\x01\x66\x00\x00\x0a\x06\x01\x04\x00\x41\x01\x0b");
+
+// register.txt:6
+register("A", $1)
+
+// register.txt:8
+let $2 = instance("\x00\x61\x73\x6d\x01\x00\x00\x00\x01\x05\x01\x60\x00\x01\x7f\x02\x07\x01\x01\x41\x01\x66\x00\x00\x03\x02\x01\x00\x07\x05\x01\x01\x67\x00\x01\x0a\x06\x01\x04\x00\x10\x00\x0b");
+
+// register.txt:12
+assert_return(() => call($2, "g", []), 1);
+
 ;;; STDOUT ;;)
diff --git a/test/gen-spec-prefix.js b/test/gen-spec-prefix.js
index ed68c84d..0ce7ce46 100644
--- a/test/gen-spec-prefix.js
+++ b/test/gen-spec-prefix.js
@@ -1,9 +1,7 @@
 /* Lovingly generated by gen-spec-js.py based on the wonderful content of *
- * https://github.com/WebAssembly/spec/blob/master/interpreter/host/js.ml */
+ * https://github.com/WebAssembly/spec/blob/master/interpreter/script/js.ml */
 'use strict';
 
-let soft_validate = true;
-
 let spectest = {
   print: print || ((...xs) => console.log(...xs)),
   global: 666,
@@ -11,18 +9,26 @@ let spectest = {
   memory: new WebAssembly.Memory({initial: 1, maximum: 2}),};
 
 let registry = {spectest};
-let $$;
 
 function register(name, instance) {
   registry[name] = instance.exports;
 }
 
-function module(bytes) {
+function module(bytes, valid = true) {
   let buffer = new ArrayBuffer(bytes.length);
   let view = new Uint8Array(buffer);
   for (let i = 0; i < bytes.length; ++i) {
     view[i] = bytes.charCodeAt(i);
   }
+  let validated;
+  try {
+    validated = WebAssembly.validate(buffer);
+  } catch (e) {
+    throw new Error("Wasm validate throws");
+  }
+  if (validated !== valid) {
+    throw new Error("Wasm validate failure" + (valid ? "" : " expected"));
+  }
   return new WebAssembly.Module(buffer);
 }
 
@@ -30,29 +36,40 @@ function instance(bytes, imports = registry) {
   return new WebAssembly.Instance(module(bytes), imports);
 }
 
+function instance(bytes, imports = registry) {
+  return new WebAssembly.Instance(module(bytes), imports);
+}
+
+function call(instance, name, args) {
+  return instance.exports[name](...args);
+}
+
+function get(instance, name) {
+  return instance.exports[name];
+}
+
+function exports(name, instance) {
+  return {[name]: instance.exports};
+}
+
+function run(action) {
+  action();
+}
+
 function assert_malformed(bytes) {
-  try { module(bytes) } catch (e) {
+  try { module(bytes, false) } catch (e) {
     if (e instanceof WebAssembly.CompileError) return;
   }
   throw new Error("Wasm decoding failure expected");
 }
 
 function assert_invalid(bytes) {
-  try { module(bytes) } catch (e) {
+  try { module(bytes, false) } catch (e) {
     if (e instanceof WebAssembly.CompileError) return;
   }
   throw new Error("Wasm validation failure expected");
 }
 
-function assert_soft_invalid(bytes) {
-  try { module(bytes) } catch (e) {
-    if (e instanceof WebAssembly.CompileError) return;
-    throw new Error("Wasm validation failure expected");
-  }
-  if (soft_validate)
-    throw new Error("Wasm validation failure expected");
-}
-
 function assert_unlinkable(bytes) {
   let mod = module(bytes);
   try { new WebAssembly.Instance(mod, registry) } catch (e) {
@@ -76,6 +93,16 @@ function assert_trap(action) {
   throw new Error("Wasm trap expected");
 }
 
+let StackOverflow;
+try { (function f() { 1 + f() })() } catch (e) { StackOverflow = e.constructor }
+
+function assert_exhaustion(action) {
+  try { action() } catch (e) {
+    if (e instanceof StackOverflow) return;
+  }
+  throw new Error("Wasm resource exhaustion expected");
+}
+
 function assert_return(action, expected) {
   let actual = action();
   if (!Object.is(actual, expected)) {
@@ -93,19 +120,12 @@ function assert_return_canonical_nan(action) {
 }
 
 function assert_return_arithmetic_nan(action) {
-  let actual = action();
   // Note that JS can't reliably distinguish different NaN values,
-  // so there's no good way to test that it's a canonical NaN.
+  // so there's no good way to test for specific bitpatterns here.
+  let actual = action();
   if (!Number.isNaN(actual)) {
     throw new Error("Wasm return value NaN expected, got " + actual);
   };
 }
 
-function assert_exhaustion(action) {
-  try { action() } catch (e) {
-    if (e instanceof RangeError) return;
-  }
-  throw new Error("RangeError expected");
-}
-
 let f32 = Math.fround;