Fix a regression in character-at stub when doing a keyed load on a string. ...

test/mjsunit/regress/regress-900966.js

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@@ skipping 11 matching lines @@
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 assertTrue('abc'[10] === undefined);
 String.prototype[10] = 'x';
 assertEquals('abc'[10], 'x');
 
+// Test that the fast case character-at stub handles an out-of-bound
+// index correctly. We need to call the function twice to initialize
+// the character-at stub.
+function f() {
+  assertEquals('abc'[10], 'x');
+}
+f();

[Kasper Lund, 2010/09/16 09:17:05]

Add a comment about why you need two calls here.

+f();
+
 assertTrue(2[11] === undefined);
 Number.prototype[11] = 'y';
 assertEquals(2[11], 'y');
 
 assertTrue(true[12] === undefined);
 Boolean.prototype[12] = 'z';
 assertEquals(true[12], 'z');