diff options
author | Adriaan Moors <adriaan.moors@typesafe.com> | 2014-01-15 14:13:53 -0800 |
---|---|---|
committer | Adriaan Moors <adriaan.moors@typesafe.com> | 2014-01-15 14:13:53 -0800 |
commit | 4f7ff0ad530fee6d75c95194ecec87a8c1ce4486 (patch) | |
tree | 8296f1d33ddb46c61102c40d3ee12a81540f5c4a /test/junit | |
parent | 6ea9933e262ab286165511a90f3e1df341e032a4 (diff) | |
parent | 29541ce3961a797836b232ccc12a60cc09f5de3e (diff) | |
download | scala-4f7ff0ad530fee6d75c95194ecec87a8c1ce4486.tar.gz scala-4f7ff0ad530fee6d75c95194ecec87a8c1ce4486.tar.bz2 scala-4f7ff0ad530fee6d75c95194ecec87a8c1ce4486.zip |
Merge pull request #3316 from Ichoran/topic/big-decimal-correctness
Quasi-comprehensive BigDecimal soundness/correctness fix.
Diffstat (limited to 'test/junit')
-rw-r--r-- | test/junit/scala/math/BigDecimalTest.scala | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/test/junit/scala/math/BigDecimalTest.scala b/test/junit/scala/math/BigDecimalTest.scala new file mode 100644 index 0000000000..d1ba96fcc8 --- /dev/null +++ b/test/junit/scala/math/BigDecimalTest.scala @@ -0,0 +1,225 @@ +package scala.math + +import org.junit.runner.RunWith +import org.junit.runners.JUnit4 +import org.junit.Test +import java.math.{BigDecimal => BD, MathContext => MC} + +/* Tests various maps by making sure they all agree on the same answers. */ +@RunWith(classOf[JUnit4]) +class BigDecimalTest { + + // Motivated by SI-6173: BigDecimal#isWhole implementation is very heap intensive + @Test + def isWholeTest() { + val wholes = List( + BigDecimal(1), + BigDecimal(10L), + BigDecimal(14.000), + BigDecimal(new BD("19127981892347012385719827340123471923850195")), + BigDecimal("1e1000000000"), + BigDecimal(14.1928857191985e22), + BigDecimal(14.12519823759817, new MC(2)) + ) + val fracs = List( + BigDecimal(0.1), + BigDecimal(new BD("1.000000000000000000000000000000000001")), + BigDecimal(new BD("275712375971892375127591745810580123751.99999")), + BigDecimal("14.19238571927581e6"), + BigDecimal("912834718237510238591285")/2 + ) + assert(wholes.forall(_.isWhole) && fracs.forall(! _.isWhole)) + } + + // Motivated by SI-6699: BigDecimal.isValidDouble behaves unexpectedly + @Test + def isValidDoubleTest() { + val valids = List( + BigDecimal(1), + BigDecimal(19571.125), + BigDecimal.decimal(0.1), + BigDecimal(1e15) + ) + val invalids = List( + BigDecimal(new BD("1.0000000000000000000000000000000000000000001")), + BigDecimal("10e1000000"), + BigDecimal("10e-1000000") + ) + assert( + valids.forall(_.isDecimalDouble) && + invalids.forall(! _.isDecimalDouble) + ) + } + + // Motivated by SI-6173: BigDecimal#isWhole implementation is very heap intensive + @Test + def doesNotExplodeTest() { + val troublemaker = BigDecimal("1e1000000000") + val reasonable = BigDecimal("1e1000") + val reasonableInt = reasonable.toBigInt + assert( + reasonable.hashCode == reasonableInt.hashCode && + reasonable == reasonableInt && + reasonableInt == reasonable && + troublemaker.hashCode != reasonable.hashCode && + !(troublemaker == reasonableInt) && + !(reasonableInt == troublemaker) + ) + } + + // Motivated by SI-6456: scala.math.BigDecimal should not accept a null value + @Test + def refusesNullTest() { + def isIAE[A](a: => A) = try { a; false } catch { case iae: IllegalArgumentException => true } + def isNPE[A](a: => A) = try { a; false } catch { case npe: NullPointerException => true } + assert( + isIAE(new BigDecimal(null: BD, new MC(2))) && + isIAE(new BigDecimal(new BD("5.7"), null: MC)) && + isNPE(BigDecimal(null: BigInt)) && + isNPE(BigDecimal(null: String)) && + isNPE(BigDecimal(null: Array[Char])) + ) + } + + // Motivated by SI-6153: BigDecimal.hashCode() has high collision rate + @Test + def hashCodesAgreeTest() { + val bi: BigInt = 100000 + val bd: BigDecimal = 100000 + val l: Long = 100000 + val d: Double = 100000 + assert( + d.## == l.## && + l.## == bd.## && + bd.## == bi.## && + (bd pow 4).hashCode == (bi pow 4).hashCode && + BigDecimal("1e150000").hashCode != BigDecimal("1e150000").toBigInt.hashCode + ) + } + + // Motivated by noticing BigDecimal(0.1f) != BigDecimal(0.1) + @Test + def consistentTenthsTest() { + def tenths = List[Any]( + BigDecimal("0.1"), + 0.1, + BigDecimal.decimal(0.1f), + BigDecimal.decimal(0.1), + BigDecimal(0.1), + BigDecimal(BigInt(1), 1), + BigDecimal(new BD("0.1")), + BigDecimal(1L, 1), + BigDecimal(1) / BigDecimal(10), + BigDecimal(10).pow(-1) + ) + for (a <- tenths; b <- tenths) assert(a == b, s"$a != $b but both should be 0.1") + } + + // Motivated by noticing BigDecimal(123456789, mc6) != BigDecimal(123456789L, mc6) + // where mc6 is a MathContext that rounds to six digits + @Test + def consistentRoundingTest() { + val mc6 = new MC(6) + val sameRounding = List( + List( + 123457000, + 123457000L, + 123457e3, + BigDecimal(123456789, mc6), + BigDecimal(123456789L, mc6), + BigDecimal(123456789d, mc6), + BigDecimal("123456789", mc6), + BigDecimal(Array('1','2','3','4','5','6','7','8','9'), mc6), + BigDecimal(BigInt(123456789), mc6), + BigDecimal(BigInt(1234567890), 1, mc6), + BigDecimal.decimal(123456789, mc6), + BigDecimal.decimal(123456789d, mc6), + BigDecimal.decimal(new BD("123456789"), mc6) + ), + List( + 123456789, + 123456789L, + 123456789d, + new BigDecimal(new BD("123456789"), mc6), + new BigDecimal(new BD("123456789")), + BigDecimal(123456789), + BigDecimal(123456789L), + BigDecimal(123456789d), + BigDecimal("123456789"), + BigDecimal(Array('1','2','3','4','5','6','7','8','9')), + BigDecimal(BigInt(123456789)), + BigDecimal(BigInt(1234567890), 1), + BigDecimal.decimal(123456789), + BigDecimal.decimal(123456789d), + BigDecimal.valueOf(123456789d, mc6) + ) + ) + sameRounding.map(_.zipWithIndex).foreach{ case xs => + for ((a,i) <- xs; (b,j) <- xs) { + assert(a == b, s"$a != $b (#$i != #$j) but should be the same") + assert(a.## == b.##, s"Hash code mismatch in equal BigDecimals: #$i != #$j") + } + } + val List(xs, ys) = sameRounding.map(_.zipWithIndex) + for ((a,i) <- xs; (b,j) <- ys) assert(a != b, s"$a == $b (#$i == #$j) but should be different") + } + + // This was unexpectedly truncated in 2.10 + @Test + def noPrematureRoundingTest() { + val text = "9791375983750284059237954823745923845928547807345082378340572986452364" + val same = List[Any]( + BigInt(text), BigDecimal(text), BigDecimal(new BD(text)) + ) + for (a <- same; b <- same) assert(a == b, s"$a != $b but should be the same") + } + + // Tests attempts to make sane the representation of IEEE binary32 and binary64 + // (i.e. Float and Double) with Scala's text-is-King BigDecimal policy + @Test + def churnRepresentationTest() { + val rn = new scala.util.Random(42) + for (i <- 1 to 1000) { + val d = rn.nextDouble + assert({ + BigDecimal.decimal(d).isDecimalDouble && + BigDecimal.binary(d).isBinaryDouble && + BigDecimal.exact(d).isExactDouble + }, s"At least one wrong BigDecimal representation for $d") + } + for (i <- 1 to 1000) { + val f = rn.nextFloat + assert({ + BigDecimal.decimal(f).isDecimalFloat && + BigDecimal.binary(f).isBinaryFloat && + BigDecimal.exact(f).isExactFloat + }, s"At least one wrong BigDecimal representation for $f") + } + for (i <- 1 to 1000) { + val ndig = 15+rn.nextInt(5) + val s = Array.fill(ndig)((rn.nextInt(10)+'0').toChar).mkString + val bi = BigInt(s) + val l = bi.toLong + val d = bi.toDouble + val bd = BigDecimal(bi) + val bd2 = BigDecimal.decimal(d) + assert(!bi.isValidLong || bi == l, s"Should be invalid or equal: $bi $l") + assert(!bi.isValidDouble || bi == d, s"Should be invalid or equal: $bi $d") + assert(bd == bi, s"Should be equal $bi $bd") + assert(bd.## == bi.##, s"Hash codes for $bi, $bd should be equal") + assert(bd == bd2 || bd2 != BigDecimal.exact(d) || !bi.isValidDouble, + s"$bd != $bd2 should only be when inexact or invalid") + assert(d == bd2 && bd2 == d, s"$d != $bd2 but they should equal") + } + val different = List( + BigDecimal.decimal(0.1), + BigDecimal.binary(0.1), + BigDecimal.binary(0.1, new MC(25)), + BigDecimal.exact(0.1), + BigDecimal.exact(0.1f), + BigDecimal.decimal((0.1f).toDouble) + ) + for (a <- different; b <- different if (a ne b)) + assert(a != b, "BigDecimal representations of Double mistakenly conflated") + } +} |