Only look up .stack property on exception objects (#905)

bnoordhuis · web-flow · commit f507557e99ec · 2025-02-10T09:58:48.000+01:00
Without this additional check, run-test262 prints "TypeError: cannot
read property 'stack' of undefined" when a test throws undefined,
obscuring the actual error.
diff --git a/run-test262.c b/run-test262.c
@@ -1548,7 +1548,7 @@ static int eval_buf(JSContext *ctx, const char *buf, size_t buf_len,
                 }
             }
         }
-        if (is_unexpected_error && verbose > 1) {
+        if (is_unexpected_error && verbose > 1 && JS_IsException(exception_val)) {
             JSValue val = JS_GetPropertyStr(ctx, exception_val, "stack");
             if (!JS_IsException(val) &&
                 !JS_IsUndefined(val) &&

Original file line number	Diff line number	Diff line change
`@@ -1548,7 +1548,7 @@ static int eval_buf(JSContext ctx, const char buf, size_t buf_len,`
`1548`	`1548`	`}`
`1549`	`1549`	`}`
`1550`	`1550`	`}`
`1551`		`- if (is_unexpected_error && verbose > 1) {`
	`1551`	`+ if (is_unexpected_error && verbose > 1 && JS_IsException(exception_val)) {`
`1552`	`1552`	`JSValue val = JS_GetPropertyStr(ctx, exception_val, "stack");`
`1553`	`1553`	`if (!JS_IsException(val) &&`
`1554`	`1554`	`!JS_IsUndefined(val) &&`