Bug 5308 – Number.toFixed doesn't include leading zero

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Bob Ippolito]

(0.5).toFixed(1) is ".5".  (0.5).toString() is "0.5" and other browsers return "0.5" for both.

[Ricci Adams]

ECMA-262 Section 15.7.4.5 states that:

13. Let k be the number of characters in m.
14. If k > f, go to step 18.

We are implementing this by creating an if block containing steps 15-17.  Unfortuately, the statement 
we are using is:

      if (m.size() < f) {
            // Execute steps 15-17
      }
      // Step 18...

Hence, we are assuming that (k > f) is the same as !(k < f).  This is logically not the case.  I believe that 
the correct line is:

      if (m.size() <= f) {

Unfortuately, I'm too tired to create/test a patch now.  I will try to attach one later this week.

[Ricci Adams]

Created attachment 5468 [details]
Patch and test case for 5308

Patch attached.  This is basically changing the < to a <=.  I also changed
m.size() to k in order to make the code read more like the algorithm.

[Eric Seidel (no email)]

Comment on attachment 5468 [details]
Patch and test case for 5308

Looks fine.  An even better test case would print "success" or "failure" to be
more clear.