StringToDouble rewritten not using String::Get and memory allocations.

It converts the number to "canonical" form removing insignificant digits,
leading zerroes and spaces what guarantees to fit a fixed size buffer and
does not changes result of strtod.
Review URL: http://codereview.chromium.org/1216005

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4282 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

test/cctest/test-conversions.cc

@@ -41,6 +41,10 @@ TEST(Octal) {
   CHECK_EQ(7.0, StringToDouble("07", ALLOW_HEX));
   CHECK_EQ(10.0, StringToDouble("010", ALLOW_HEX));
   CHECK_EQ(77.0, StringToDouble("077", ALLOW_HEX));
+
+  const double x = 010000000000;  // Power of 2, no rounding errors.
+  CHECK_EQ(x * x * x * x * x, StringToDouble("01" "0000000000" "0000000000"
+      "0000000000" "0000000000" "0000000000", ALLOW_OCTALS));
 }
 
 
@@ -80,6 +84,8 @@ TEST(MalformedOctal) {
 TEST(TrailingJunk) {
   CHECK_EQ(8.0, StringToDouble("8q", ALLOW_TRAILING_JUNK));
   CHECK_EQ(63.0, StringToDouble("077qqq", ALLOW_OCTALS | ALLOW_TRAILING_JUNK));
+  CHECK_EQ(10.0, StringToDouble("10e", ALLOW_OCTALS | ALLOW_TRAILING_JUNK));
+  CHECK_EQ(10.0, StringToDouble("10e-", ALLOW_OCTALS | ALLOW_TRAILING_JUNK));
 }
 
 
@@ -91,6 +97,87 @@ TEST(NonStrDecimalLiteral) {
   CHECK_EQ(0.0, StringToDouble(" ", NO_FLAGS));
 }
 
+TEST(IntegerStrLiteral) {
+  CHECK_EQ(0.0, StringToDouble("0.0", NO_FLAGS));
+  CHECK_EQ(0.0, StringToDouble("0", NO_FLAGS));
+  CHECK_EQ(0.0, StringToDouble("00", NO_FLAGS));
+  CHECK_EQ(0.0, StringToDouble("000", NO_FLAGS));
+  CHECK_EQ(1.0, StringToDouble("1", NO_FLAGS));
+  CHECK_EQ(-1.0, StringToDouble("-1", NO_FLAGS));
+  CHECK_EQ(-1.0, StringToDouble("  -  1  ", NO_FLAGS));
+  CHECK_EQ(1.0, StringToDouble("  +  1  ", NO_FLAGS));
+
+  CHECK_EQ(0.0, StringToDouble("0e0", ALLOW_HEX | ALLOW_OCTALS));
+  CHECK_EQ(0.0, StringToDouble("0e1", ALLOW_HEX | ALLOW_OCTALS));
+  CHECK_EQ(0.0, StringToDouble("0e-1", ALLOW_HEX | ALLOW_OCTALS));
+  CHECK_EQ(0.0, StringToDouble("0e-100000", ALLOW_HEX | ALLOW_OCTALS));
+  CHECK_EQ(0.0, StringToDouble("0e+100000", ALLOW_HEX | ALLOW_OCTALS));
+  CHECK_EQ(0.0, StringToDouble("0.", ALLOW_HEX | ALLOW_OCTALS));
+}
+
+TEST(LongNumberStr) {
+  CHECK_EQ(1e10, StringToDouble("1" "0000000000", NO_FLAGS));
+  CHECK_EQ(1e20, StringToDouble("1" "0000000000" "0000000000", NO_FLAGS));
+
+  CHECK_EQ(1e60, StringToDouble("1" "0000000000" "0000000000" "0000000000"
+      "0000000000" "0000000000" "0000000000", NO_FLAGS));
+
+  CHECK_EQ(1e-2, StringToDouble("." "0" "1", NO_FLAGS));
+  CHECK_EQ(1e-11, StringToDouble("." "0000000000" "1", NO_FLAGS));
+  CHECK_EQ(1e-21, StringToDouble("." "0000000000" "0000000000" "1", NO_FLAGS));
+
+  CHECK_EQ(1e-61, StringToDouble("." "0000000000" "0000000000" "0000000000"
+      "0000000000" "0000000000" "0000000000" "1", NO_FLAGS));
+
+
+  // x = 24414062505131248.0 and y = 24414062505131252.0 are representable in
+  // double. Check chat z = (x + y) / 2 is rounded to x...
+  CHECK_EQ(24414062505131248.0,
+           StringToDouble("24414062505131250.0", NO_FLAGS));
+
+  // ... and z = (x + y) / 2 + delta is rounded to y.
+  CHECK_EQ(24414062505131252.0,
+           StringToDouble("24414062505131250.000000001", NO_FLAGS));
+}
+
+
+extern "C" double gay_strtod(const char* s00, const char** se);
+
+
+TEST(MaximumSignificantDigits) {
+  char num[] =
+      "4.4501477170144020250819966727949918635852426585926051135169509"
+      "122872622312493126406953054127118942431783801370080830523154578"
+      "251545303238277269592368457430440993619708911874715081505094180"
+      "604803751173783204118519353387964161152051487413083163272520124"
+      "606023105869053620631175265621765214646643181420505164043632222"
+      "668006474326056011713528291579642227455489682133472873831754840"
+      "341397809846934151055619529382191981473003234105366170879223151"
+      "087335413188049110555339027884856781219017754500629806224571029"
+      "581637117459456877330110324211689177656713705497387108207822477"
+      "584250967061891687062782163335299376138075114200886249979505279"
+      "101870966346394401564490729731565935244123171539810221213221201"
+      "847003580761626016356864581135848683152156368691976240370422601"
+      "6998291015625000000000000000000000000000000000e-308";
+
+  CHECK_EQ(gay_strtod(num, NULL), StringToDouble(num, NO_FLAGS));
+
+  // Changes the result of strtod (at least in glibc implementation).
+  num[sizeof(num) - 8] = '1';
+
+  CHECK_EQ(gay_strtod(num, NULL), StringToDouble(num, NO_FLAGS));
+}
+
+
+TEST(ExponentNumberStr) {
+  CHECK_EQ(1e1, StringToDouble("1e1", NO_FLAGS));
+  CHECK_EQ(1e1, StringToDouble("1e+1", NO_FLAGS));
+  CHECK_EQ(1e-1, StringToDouble("1e-1", NO_FLAGS));
+  CHECK_EQ(1e100, StringToDouble("1e+100", NO_FLAGS));
+  CHECK_EQ(1e-100, StringToDouble("1e-100", NO_FLAGS));
+  CHECK_EQ(1e-106, StringToDouble(".000001e-100", NO_FLAGS));
+}
+
 class OneBit1: public BitField<uint32_t, 0, 1> {};
 class OneBit2: public BitField<uint32_t, 7, 1> {};
 class EightBit1: public BitField<uint32_t, 0, 8> {};

test/mjsunit/str-to-num.js

@@ -29,6 +29,19 @@ function toNumber(val) {
   return Number(val);
 }
 
+function repeat(s, num) {
+  var result = '';
+  while (num > 0) {
+    if ((num & 1) != 0) result += s;
+    s += s;
+    num >>= 1;
+  }
+
+  return result;
+}
+
+assertEquals('0000000000', repeat('0', 10));
+
 // assertEquals(, toNumber());
 
 
@@ -61,6 +74,7 @@ assertEquals(Infinity,  toNumber("+Infinity "), "+Infinity");
 assertEquals(0,  toNumber("0"));
 assertEquals(0,  toNumber("+0"));
 assertEquals(-0, toNumber("-0"));
+assertEquals(-Infinity, 1 / toNumber("-0"));
 
 assertEquals(1,  toNumber("1"));
 assertEquals(1,  toNumber("+1"));
@@ -130,11 +144,16 @@ assertEquals(15, toNumber("0Xf"));
 assertEquals(15, toNumber("0XF"));
 
 assertEquals(0,  toNumber("0x000"));
+assertEquals(-Infinity,  1 / toNumber("-0x000"));
+assertEquals(0,  toNumber("0x000" + repeat('0', 1000)));
 assertEquals(9,  toNumber("0x009"));
 assertEquals(10, toNumber("0x00a"));
 assertEquals(10, toNumber("0x00A"));
 assertEquals(15, toNumber("0x00f"));
 assertEquals(15, toNumber("0x00F"));
+assertEquals(Infinity,  toNumber("0x" + repeat('0', 1000) + '1'
+                        + repeat('0', 1000)));
+assertEquals(-Infinity,  toNumber("-0x1" + repeat('0', 1000)));
 
 assertEquals(0, toNumber("00"));
 assertEquals(1, toNumber("01"));
@@ -156,3 +175,6 @@ assertTrue(isNaN(toNumber("0x100 junk")), "0x100 junk");
 assertTrue(isNaN(toNumber("100.0 junk")), "100.0 junk");
 assertTrue(isNaN(toNumber(".1e4 junk")), ".1e4 junk");
 assertTrue(isNaN(toNumber("Infinity junk")), "Infinity junk");
+assertTrue(isNaN(toNumber("1e")), "1e");
+assertTrue(isNaN(toNumber("1e ")), "1e_");
+assertTrue(isNaN(toNumber("1" + repeat('0', 1000) + 'junk')), "1e1000 junk");