Fix Decimal.floor() + Decimal.ceiling() for most non-integral values.

Source/platform/DecimalTest.cpp

 /*
  * Copyright (C) 2012 Google Inc. 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
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 207 matching lines @@
 }
 
 TEST_F(DecimalTest, Ceiling)
 {
     EXPECT_EQ(Decimal(1), Decimal(1).ceiling());
     EXPECT_EQ(Decimal(1), encode(1, -10, Positive).ceiling());
     EXPECT_EQ(Decimal(2), encode(11, -1, Positive).ceiling());
     EXPECT_EQ(Decimal(2), encode(13, -1, Positive).ceiling());
     EXPECT_EQ(Decimal(2), encode(15, -1, Positive).ceiling());
     EXPECT_EQ(Decimal(2), encode(19, -1, Positive).ceiling());
+    EXPECT_EQ(Decimal(2), encode(151, -2, Positive).ceiling());
+    EXPECT_EQ(Decimal(2), encode(101, -2, Positive).ceiling());
+    EXPECT_EQ(Decimal(1), encode(199, -3, Positive).ceiling());
+    EXPECT_EQ(Decimal(2), encode(199, -2, Positive).ceiling());
+    EXPECT_EQ(Decimal(3), encode(209, -2, Positive).ceiling());
 
     EXPECT_EQ(Decimal(-1), Decimal(-1).ceiling());
     EXPECT_EQ(Decimal(0), encode(1, -10, Negative).ceiling());
     EXPECT_EQ(Decimal(-1), encode(11, -1, Negative).ceiling());
     EXPECT_EQ(Decimal(-1), encode(13, -1, Negative).ceiling());
     EXPECT_EQ(Decimal(-1), encode(15, -1, Negative).ceiling());
     EXPECT_EQ(Decimal(-1), encode(19, -1, Negative).ceiling());
+    EXPECT_EQ(Decimal(-1), encode(151, -2, Negative).ceiling());
+    EXPECT_EQ(Decimal(-1), encode(101, -2, Negative).ceiling());
+    EXPECT_EQ(Decimal(0), encode(199, -3, Negative).ceiling());
+    EXPECT_EQ(Decimal(-1), encode(199, -2, Negative).ceiling());
+    EXPECT_EQ(Decimal(-2), encode(209, -2, Negative).ceiling());
 }
 
 TEST_F(DecimalTest, CeilingBigExponent)
 {
     EXPECT_EQ(encode(1, 1000, Positive), encode(1, 1000, Positive).ceiling());
     EXPECT_EQ(encode(1, 1000, Negative), encode(1, 1000, Negative).ceiling());
 }
 
 TEST_F(DecimalTest, CeilingSmallExponent)
 {
@@ skipping 311 matching lines @@
 }
 
 TEST_F(DecimalTest, Floor)
 {
     EXPECT_EQ(Decimal(1), Decimal(1).floor());
     EXPECT_EQ(Decimal(0), encode(1, -10, Positive).floor());
     EXPECT_EQ(Decimal(1), encode(11, -1, Positive).floor());
     EXPECT_EQ(Decimal(1), encode(13, -1, Positive).floor());
     EXPECT_EQ(Decimal(1), encode(15, -1, Positive).floor());
     EXPECT_EQ(Decimal(1), encode(19, -1, Positive).floor());
+    EXPECT_EQ(Decimal(1), encode(193332, -5, Positive).floor());
+    EXPECT_EQ(Decimal(12), encode(12002, -3, Positive).floor());
 
     EXPECT_EQ(Decimal(-1), Decimal(-1).floor());
     EXPECT_EQ(Decimal(-1), encode(1, -10, Negative).floor());
     EXPECT_EQ(Decimal(-2), encode(11, -1, Negative).floor());
     EXPECT_EQ(Decimal(-2), encode(13, -1, Negative).floor());
     EXPECT_EQ(Decimal(-2), encode(15, -1, Negative).floor());
     EXPECT_EQ(Decimal(-2), encode(19, -1, Negative).floor());
+    EXPECT_EQ(Decimal(-2), encode(193332, -5, Negative).floor());
+    EXPECT_EQ(Decimal(-13), encode(12002, -3, Negative).floor());
 }
 
 TEST_F(DecimalTest, FloorBigExponent)
 {
     EXPECT_EQ(encode(1, 1000, Positive), encode(1, 1000, Positive).floor());
     EXPECT_EQ(encode(1, 1000, Negative), encode(1, 1000, Negative).floor());
 }
 
 TEST_F(DecimalTest, FloorSmallExponent)
 {
@@ skipping 369 matching lines @@
     EXPECT_EQ(Decimal(1), (Decimal(9) / Decimal(10)).round());
     EXPECT_EQ(Decimal(25), (Decimal(5) / fromString("0.200")).round());
     EXPECT_EQ(Decimal(3), (Decimal(5) / Decimal(2)).round());
     EXPECT_EQ(Decimal(1), (Decimal(2) / Decimal(3)).round());
     EXPECT_EQ(Decimal(3), (Decimal(10) / Decimal(3)).round());
     EXPECT_EQ(Decimal(3), (Decimal(1) / fromString("0.3")).round());
     EXPECT_EQ(Decimal(10), (Decimal(1) / fromString("0.1")).round());
     EXPECT_EQ(Decimal(5), (Decimal(1) / fromString("0.2")).round());
     EXPECT_EQ(Decimal(10), (fromString("10.2") / 1).round());
     EXPECT_EQ(encode(1234, 100, Positive), encode(1234, 100, Positive).round());
+
+    EXPECT_EQ(Decimal(2), encode(190002, -5, Positive).round());
+    EXPECT_EQ(Decimal(2), encode(150002, -5, Positive).round());
+    EXPECT_EQ(Decimal(2), encode(150000, -5, Positive).round());
+    EXPECT_EQ(Decimal(12), encode(12492, -3, Positive).round());
+    EXPECT_EQ(Decimal(13), encode(12502, -3, Positive).round());
+
+    EXPECT_EQ(Decimal(-2), encode(190002, -5, Negative).round());
+    EXPECT_EQ(Decimal(-2), encode(150002, -5, Negative).round());
+    EXPECT_EQ(Decimal(-2), encode(150000, -5, Negative).round());
+    EXPECT_EQ(Decimal(-12), encode(12492, -3, Negative).round());
+    EXPECT_EQ(Decimal(-13), encode(12502, -3, Negative).round());
 }
 
 TEST_F(DecimalTest, RoundSpecialValues)
 {
     EXPECT_EQ(Decimal::infinity(Positive), Decimal::infinity(Positive).round());
     EXPECT_EQ(Decimal::infinity(Negative), Decimal::infinity(Negative).round());
     EXPECT_EQ(Decimal::nan(), Decimal::nan().round());
 }
 
 TEST_F(DecimalTest, Subtract)
@@ skipping 116 matching lines @@
     EXPECT_DECIMAL_STREQ("0.001", encode(UINT64_C(99999999999999999), -20, Positive));
     EXPECT_DECIMAL_STREQ("1e-83", encode(UINT64_C(99999999999999999), -100, Positive));
 }
 
 TEST_F(DecimalTest, ToStringSpecialValues)
 {
     EXPECT_DECIMAL_STREQ("Infinity", Decimal::infinity(Positive));
     EXPECT_DECIMAL_STREQ("-Infinity", Decimal::infinity(Negative));
     EXPECT_DECIMAL_STREQ("NaN", Decimal::nan());
 }