make DateParser::TimeComposer handle milliseconds properly...

src/dateparser.h

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 69 matching lines @@
     // Read a string of digits as an unsigned number (cap just below kMaxInt).
     int ReadUnsignedNumber() {
       has_read_number_ = true;
       int n;
       for (n = 0; IsAsciiDigit() && n < kMaxInt / 10 - 1; Next()) {
         n = n * 10 + ch_ - '0';
       }
       return n;
     }
 
+    // Read a string of up to three digits as an unsigned number of milliseconds
+    int ReadMilliseconds() {
+      has_read_number_ = true;
+      int n = 0;
+      int i;
+      for (i = 0; IsAsciiDigit(); Next(), i++) {
+        if (i < 3) n = n + pow(10, 2 - i) * (ch_ - '0');

[Lasse Reichstein, 2010/11/25 12:56:05]

I'm somewhat opposed to using the standard pow(double, double) to do simple
powers of integers.
How about managing the multiplier manually, i.e., set it to 100 before entering
the loop, and inside the condition, divide it by 10.
(You could even use it as the if-condition, and stop adding when it reaches zero
- or event skipping the conditional entirely, and relying on a zero multiplier
to make the addition do nothing).

[Florian Loitsch, 2010/11/25 13:55:54]

Isn't this simply:
for (int i = 0; IsAsciiDigit(); Next(), i++) {
  if (i < 3) n = n * 10 + (ch_ - '0');
}
return n;
?

[Lasse Reichstein, 2010/11/25 14:10:36]

Not if there are fewer than three digits. We need .5, .500 and .50012124 to all
map to 500.

+      }
+      return n;
+    }
+
     // Read a word (sequence of chars. >= 'A'), fill the given buffer with a
     // lower-case prefix, and pad any remainder of the buffer with zeroes.
     // Return word length.
     int ReadWord(uint32_t* prefix, int prefix_size) {
       int len;
       for (len = 0; IsAsciiAlphaOrAbove(); Next(), len++) {
         if (len < prefix_size) prefix[len] = AsciiAlphaToLower(ch_);
       }
       for (int i = len; i < prefix_size; i++) prefix[i] = 0;
       return len;
@@ skipping 142 matching lines @@
     int comp_[kSize];
     int index_;
     int named_month_;
   };
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_DATEPARSER_H_