SI-9767 document and test behaviour of String->integer/float conversions

We delegate `String`'s extension methods  `toInt`, `toFloat`, etc to corresponding
methods in the Java standard library. These differ in the way they handle
whitespace in the original string.

This commit documents and tests the current behaviour.

1 files changed, 31 insertions, 0 deletions

diff --git a/test/junit/scala/collection/immutable/StringLikeTest.scala b/test/junit/scala/collection/immutable/StringLikeTest.scala
index 50be638b89..44bade860e 100644
--- a/test/junit/scala/collection/immutable/StringLikeTest.scala
+++ b/test/junit/scala/collection/immutable/StringLikeTest.scala
@@ -1,5 +1,6 @@
 package scala.collection.immutable
 
+import org.junit.Assert._
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.junit.runners.JUnit4
@@ -40,4 +41,34 @@ class StringLikeTest {
     AssertUtil.assertSameElements("--ch--omp--".split("-"), Array("", "", "ch", "", "omp")) // All the cases!
     AssertUtil.assertSameElements(twopairs.split(high), Array(twopairs)) //don't split on characters that are half a surrogate pair
   }
+
+  /* Test for SI-9767 */
+  @Test
+  def testNumericConversion: Unit = {
+    val sOne = " \t\n 1 \n\r\t "
+    val sOk  = "2"
+    val sNull:String = null
+
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sOne.toInt)
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sOne.toLong)
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sOne.toShort)
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sOne.toByte)
+    assertTrue("trim toDouble", sOne.toDouble == 1.0d)
+    assertTrue("trim toFloat", sOne.toFloat == 1.0f)
+
+    assertTrue("no trim toInt", sOk.toInt == 2)
+    assertTrue("no trim toLong", sOk.toLong == 2L)
+    assertTrue("no trim toShort", sOk.toShort == 2.toShort)
+    assertTrue("no trim toByte", sOk.toByte == 2.toByte)
+    assertTrue("no trim toDouble", sOk.toDouble == 2.0d)
+    assertTrue("no trim toFloat", sOk.toFloat == 2.0f)
+
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sNull.toInt, {s => s == "null"})
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sNull.toLong, {s => s == "null"})
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sNull.toShort, {s => s == "null"})
+    AssertUtil.assertThrows[java.lang.NumberFormatException](sNull.toByte, {s => s == "null"})
+
+    AssertUtil.assertThrows[java.lang.NullPointerException](sNull.toDouble)
+    AssertUtil.assertThrows[java.lang.NullPointerException](sNull.toFloat)
+  }
 }