Changeset 69833 in webkit for trunk/JavaScriptCore/wtf/DateMath.cpp

Timestamp:

Oct 14, 2010, 7:45:03 PM (15 years ago)

Author:

[email protected]

Message:

2010-10-14 Nathan Vander Wilt <​[email protected]>

Reviewed by Darin Adler.

Added parser for ECMAScript 5 standard date format, so Date.parse can handle RFC 3339 timestamps: ​https://bugs.webkit.org/show_bug.cgi?id=44632

• runtime/DateConversion.cpp: (JSC::parseDate):
• wtf/DateMath.cpp: (WTF::ymdhmsToSeconds): (WTF::parseES5DateFromNullTerminatedCharacters):
• wtf/DateMath.h:

2010-10-14 Nathan Vander Wilt <​[email protected]>

Reviewed by Darin Adler.

Added tests for ​https://bugs.webkit.org/show_bug.cgi?id=44632

• fast/js/date-parse-test-expected.txt:
• fast/js/script-tests/date-parse-test.js: (testDateParseExact):

File:

• trunk/JavaScriptCore/wtf/DateMath.cpp (modified) (3 diffs)

trunk/JavaScriptCore/wtf/DateMath.cpp

@@ -4 +4 @@
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2007-2009 Torch Mobile, Inc.
+ * Copyright (C) 2010 &yet, LLC. ([email protected])
  *
  * The Original Code is Mozilla Communicator client code, released
@@ -480 +481 @@
 }
 
-static inline double ymdhmsToSeconds(long year, int mon, int day, int hour, int minute, int second)
+static inline double ymdhmsToSeconds(long year, int mon, int day, int hour, int minute, double second)
 {
     double days = (day - 32075)
@@ -556 +557 @@
         return false;
     return true;
+}
+
+double parseES5DateFromNullTerminatedCharacters(const char* dateString)
+{
+    // This parses a date of the form defined in ECMA-262-5, section 15.9.1.15
+    // (similar to RFC 3339 / ISO 8601: YYYY-MM-DDTHH:mm:ss[.sss]Z).
+    // In most cases it is intentionally strict (e.g. correct field widths, no stray whitespace).
+    
+    static const long daysPerMonth[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+    
+    const char* currentPosition = dateString;
+    char* postParsePosition;
+    
+    // This is a bit more lenient on the year string than ES5 specifies:
+    // instead of restricting to 4 digits (or 6 digits with mandatory +/-),
+    // it accepts any integer value. Consider this an implementation fallback.
+    long year;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &year))
+        return NaN;
+    if (*postParsePosition != '-')
+        return NaN;
+    currentPosition = postParsePosition + 1;
+    
+    long month;
+    if (!isASCIIDigit(*currentPosition))
+        return NaN;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &month))
+        return NaN;
+    if (*postParsePosition != '-' || (postParsePosition - currentPosition) != 2)
+        return NaN;
+    currentPosition = postParsePosition + 1;
+    
+    long day;
+    if (!isASCIIDigit(*currentPosition))
+        return NaN;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &day))
+        return NaN;
+    if (*postParsePosition != 'T' || (postParsePosition - currentPosition) != 2)
+        return NaN;
+    currentPosition = postParsePosition + 1;
+    
+    long hours;
+    if (!isASCIIDigit(*currentPosition))
+        return NaN;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &hours))
+        return NaN;
+    if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2)
+        return NaN;
+    currentPosition = postParsePosition + 1;
+    
+    long minutes;
+    if (!isASCIIDigit(*currentPosition))
+        return NaN;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &minutes))
+        return NaN;
+    if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2)
+        return NaN;
+    currentPosition = postParsePosition + 1;
+    
+    long intSeconds;
+    if (!isASCIIDigit(*currentPosition))
+        return NaN;
+    if (!parseLong(currentPosition, &postParsePosition, 10, &intSeconds))
+        return NaN;
+    if ((postParsePosition - currentPosition) != 2)
+        return NaN;
+    
+    double seconds = intSeconds;
+    if (*postParsePosition == '.') {
+        currentPosition = postParsePosition + 1;
+        
+        // In ECMA-262-5 it's a bit unclear if '.' can be present without milliseconds, but
+        // a reasonable interpretation guided by the given examples and RFC 3339 says "no".
+        // We check the next character to avoid reading +/- timezone hours after an invalid decimal.
+        if (!isASCIIDigit(*currentPosition))
+            return NaN;
+        
+        // We are more lenient than ES5 by accepting more or less than 3 fraction digits.
+        long fracSeconds;
+        if (!parseLong(currentPosition, &postParsePosition, 10, &fracSeconds))
+            return NaN;
+        
+        long numFracDigits = postParsePosition - currentPosition;
+        seconds += fracSeconds * pow(10, -numFracDigits);
+    }
+    currentPosition = postParsePosition;
+    
+    // A few of these checks could be done inline above, but since many of them are interrelated
+    // we would be sacrificing readability to "optimize" the (presumably less common) failure path.
+    if (month < 1 || month > 12)
+        return NaN;
+    if (day < 1 || day > daysPerMonth[month - 1])
+        return NaN;
+    if (month == 2 && day > 28 && !isLeapYear(year))
+        return NaN;
+    if (hours < 0 || hours > 24)
+        return NaN;
+    if (hours == 24 && (minutes || seconds))
+        return NaN;
+    if (minutes < 0 || minutes > 59)
+        return NaN;
+    if (seconds < 0 || seconds >= 61)
+        return NaN;
+    if (seconds > 60) {
+        // Discard leap seconds by clamping to the end of a minute.
+        seconds = 60;
+    }
+    
+    long timeZoneSeconds = 0;
+    if (*currentPosition != 'Z') {
+        bool tzNegative;
+        if (*currentPosition == '-')
+            tzNegative = true;
+        else if (*currentPosition == '+')
+            tzNegative = false;
+        else
+            return NaN;
+        currentPosition += 1;
+        
+        long tzHours;
+        long tzHoursAbs;
+        long tzMinutes;
+        
+        if (!isASCIIDigit(*currentPosition))
+            return NaN;
+        if (!parseLong(currentPosition, &postParsePosition, 10, &tzHours))
+            return NaN;
+        if (*postParsePosition != ':' || (postParsePosition - currentPosition) != 2)
+            return NaN;
+        tzHoursAbs = abs(tzHours);
+        currentPosition = postParsePosition + 1;
+        
+        if (!isASCIIDigit(*currentPosition))
+            return NaN;
+        if (!parseLong(currentPosition, &postParsePosition, 10, &tzMinutes))
+            return NaN;
+        if ((postParsePosition - currentPosition) != 2)
+            return NaN;
+        currentPosition = postParsePosition;
+        
+        if (tzHoursAbs > 24)
+            return NaN;
+        if (tzMinutes < 0 || tzMinutes > 59)
+            return NaN;
+        
+        timeZoneSeconds = 60 * (tzMinutes + (60 * tzHoursAbs));
+        if (tzNegative)
+            timeZoneSeconds = -timeZoneSeconds;
+    } else {
+        currentPosition += 1;
+    }
+    if (*currentPosition)
+        return NaN;
+    
+    double dateSeconds = ymdhmsToSeconds(year, month, day, hours, minutes, seconds) - timeZoneSeconds;
+    return dateSeconds * msPerSecond;
 }