Bug 1368992 - JS bytecode cache: Do not attempt to encode bytecode if the compilation failed. r=mrbkap

2017-06-06 12:04:29 +00:00 · 2017-06-06 12:04:29 +00:00 · 558a57a171
--- a/dom/base/test/file_js_cache_syntax_error.html
+++ b/dom/base/test/file_js_cache_syntax_error.html
@ -0,0 +1,10 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Do not save bytecode on compilation errors</title>
+</head>
+<body>
+  <script id="watchme" src="file_js_cache_syntax_error.js"></script>
+</body>
+</html>
--- a/dom/base/test/file_js_cache_syntax_error.js
+++ b/dom/base/test/file_js_cache_syntax_error.js
@ -0,0 +1 @@
+var // SyntaxError: missing variable name.
--- a/dom/base/test/mochitest.ini
+++ b/dom/base/test/mochitest.ini
@ -760,6 +760,8 @@ support-files =
  file_js_cache.js
  file_js_cache_save_after_load.html
  file_js_cache_save_after_load.js
+  file_js_cache_syntax_error.html
+  file_js_cache_syntax_error.js
 [test_setInterval_uncatchable_exception.html]
 skip-if = debug == false
 [test_settimeout_extra_arguments.html]
--- a/dom/base/test/test_script_loader_js_cache.html
+++ b/dom/base/test/test_script_loader_js_cache.html
@ -191,6 +191,23 @@

    }, "Save bytecode after the initialization of the page");

+    promise_test(async function() {
+      // (see above)
+      await SpecialPowers.pushPrefEnv({set: [
+        ['dom.script_loader.bytecode_cache.enabled', true],
+        ['dom.expose_test_interfaces', true],
+        ['dom.script_loader.bytecode_cache.strategy', -1]
+      ]});
+
+      // The test page loads a script which contains a syntax error, we should
+      // not attempt to encode any bytecode for it.
+      var stateMachineResult =
+          WaitForScriptTagEvent("file_js_cache_syntax_error.html");
+      assert_equals(await stateMachineResult, "source_exec",
+                    "Check the lack of bytecode encoding");
+
+    }, "Do not save bytecode on compilation errors");
+
    done();
  </script>
 </head>
--- a/dom/script/ScriptLoader.cpp
+++ b/dom/script/ScriptLoader.cpp
@ -2132,7 +2132,7 @@ ScriptLoader::EvaluateScript(ScriptLoadRequest* aRequest)
          }

          // Queue the current script load request to later save the bytecode.
-          if (NS_SUCCEEDED(rv) && encodeBytecode) {
+          if (script && encodeBytecode) {
            aRequest->mScript = script;
            HoldJSObjects(aRequest);
            TRACE_FOR_TEST(aRequest->mElement, "scriptloader_encode");