Changeset 208410 in webkit

Timestamp:

Nov 4, 2016 5:48:01 PM (8 years ago)

Author:

mark.lam@apple.com

Message:

Error description code should be able to handle Symbol values.
​https://bugs.webkit.org/show_bug.cgi?id=164436
<rdar://problem/29115583>

Reviewed by Filip Pizlo and Saam Barati.

JSTests:

• stress/error-description-on-symbols-should-not-crash.js: Added.

Source/JavaScriptCore:

Previously, we try to toString() the Symbol value, resulting in it throwing an
exception in errorDescriptionForValue() which breaks the invariant that
errorDescriptionForValue() should not throw.

We fixed this by making errorDescriptionForValue() aware of the Symbol type, and
not so a toString() on Symbol values. Also fixed notAFunctionSourceAppender()
to build a nicer message for Symbol values.

• runtime/ExceptionHelpers.cpp:

(JSC::errorDescriptionForValue):
(JSC::notAFunctionSourceAppender):

Location:

trunk

Files:

• JSTests/ChangeLog (modified) (1 diff)
• JSTests/stress/error-description-on-symbols-should-not-crash.js (added)
• Source/JavaScriptCore/ChangeLog (modified) (1 diff)
• Source/JavaScriptCore/runtime/ExceptionHelpers.cpp (modified) (2 diffs)

trunk/JSTests/ChangeLog

@@ +1 @@
+2016-11-04  Mark Lam  <mark.lam@apple.com>
+
+        Error description code should be able to handle Symbol values.
+        https://bugs.webkit.org/show_bug.cgi?id=164436
+        <rdar://problem/29115583>
+
+        Reviewed by Filip Pizlo and Saam Barati.
+
+        * stress/error-description-on-symbols-should-not-crash.js: Added.
+
 2016-11-03  Geoffrey Garen  <ggaren@apple.com>
 

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2016-11-04  Mark Lam  <mark.lam@apple.com>
+
+        Error description code should be able to handle Symbol values.
+        https://bugs.webkit.org/show_bug.cgi?id=164436
+        <rdar://problem/29115583>
+
+        Reviewed by Filip Pizlo and Saam Barati.
+
+        Previously, we try to toString() the Symbol value, resulting in it throwing an
+        exception in errorDescriptionForValue() which breaks the invariant that
+        errorDescriptionForValue() should not throw.
+
+        We fixed this by making errorDescriptionForValue() aware of the Symbol type, and
+        not so a toString() on Symbol values.  Also fixed notAFunctionSourceAppender()
+        to build a nicer message for Symbol values.
+
+        * runtime/ExceptionHelpers.cpp:
+        (JSC::errorDescriptionForValue):
+        (JSC::notAFunctionSourceAppender):
+
 2016-11-02  Geoffrey Garen  <ggaren@apple.com>
 

trunk/Source/JavaScriptCore/runtime/ExceptionHelpers.cpp

@@ -87 +87 @@
     if (v.isString())
         return jsNontrivialString(exec, makeString('"',  asString(v)->value(exec), '"'));
+    if (v.isSymbol())
+        return jsNontrivialString(exec, asSymbol(v)->descriptiveString());
     if (v.isObject()) {
         CallData callData;
@@ -183 +185 @@
     builder.append(base);
     builder.appendLiteral("' is ");
-    if (type == TypeObject)
-        builder.appendLiteral("an instance of ");
-    builder.append(displayValue);
+    if (type == TypeSymbol)
+        builder.appendLiteral("a Symbol");
+    else {
+        if (type == TypeObject)
+            builder.appendLiteral("an instance of ");
+        builder.append(displayValue);
+    }
     builder.append(')');