diff options
| -rw-r--r-- | src/library/scala/collection/Iterator.scala | 39 | ||||
| -rw-r--r-- | test/junit/scala/collection/IteratorTest.scala | 22 |
2 files changed, 59 insertions, 2 deletions
diff --git a/src/library/scala/collection/Iterator.scala b/src/library/scala/collection/Iterator.scala index 34a025e5b8..5c4b15ad0f 100644 --- a/src/library/scala/collection/Iterator.scala +++ b/src/library/scala/collection/Iterator.scala @@ -852,8 +852,25 @@ trait Iterator[+A] extends TraversableOnce[A] { * or -1 if such an element does not exist until the end of the iterator is reached. * @note Reuse: $consumesIterator */ - def indexWhere(p: A => Boolean): Int = { + def indexWhere(p: A => Boolean): Int = indexWhere(p, 0) + + /** Returns the index of the first produced value satisfying a predicate, or -1, after or at + * some start index. + * $mayNotTerminateInf + * + * @param p the predicate to test values + * @param from the start index + * @return the index `>= from` of the first produced value satisfying `p`, + * or -1 if such an element does not exist until the end of the iterator is reached. + * @note Reuse: $consumesIterator + */ + def indexWhere(p: A => Boolean, from: Int): Int = { var i = 0 + while (i < from && hasNext) { + next() + i += 1 + } + var found = false while (!found && hasNext) { if (p(next())) { @@ -874,8 +891,26 @@ trait Iterator[+A] extends TraversableOnce[A] { * or -1 if such an element does not exist until the end of the iterator is reached. * @note Reuse: $consumesIterator */ - def indexOf[B >: A](elem: B): Int = { + def indexOf[B >: A](elem: B): Int = indexOf(elem, 0) + + /** Returns the index of the first occurrence of the specified object in this iterable object + * after or at some start index. + * $mayNotTerminateInf + * + * @param elem element to search for. + * @param from the start index + * @return the index `>= from` of the first occurrence of `elem` in the values produced by this + * iterator, or -1 if such an element does not exist until the end of the iterator is + * reached. + * @note Reuse: $consumesIterator + */ + def indexOf[B >: A](elem: B, from: Int): Int = { var i = 0 + while (i < from && hasNext) { + next() + i += 1 + } + var found = false while (!found && hasNext) { if (next() == elem) { diff --git a/test/junit/scala/collection/IteratorTest.scala b/test/junit/scala/collection/IteratorTest.scala index d5389afd0c..b3cd6707c1 100644 --- a/test/junit/scala/collection/IteratorTest.scala +++ b/test/junit/scala/collection/IteratorTest.scala @@ -135,6 +135,20 @@ class IteratorTest { assertEquals(3, List(1, 2, 3, 4, 5).iterator.indexWhere { x: Int => x >= 4 }) assertEquals(-1, List(1, 2, 3, 4, 5).iterator.indexWhere { x: Int => x >= 16 }) } + @Test def indexOfFrom(): Unit = { + assertEquals(1, List(1, 2, 3, 4, 5).iterator.indexOf(2, 0)) + assertEquals(1, List(1, 2, 3, 4, 5).iterator.indexOf(2, 1)) + assertEquals(-1, List(1, 2, 3, 4, 5).iterator.indexOf(2, 2)) + assertEquals(4, List(1, 2, 3, 2, 1).iterator.indexOf(1, 1)) + assertEquals(1, List(1, 2, 3, 2, 1).iterator.indexOf(2, 1)) + } + @Test def indexWhereFrom(): Unit = { + assertEquals(1, List(1, 2, 3, 4, 5).iterator.indexWhere(_ == 2, 0)) + assertEquals(1, List(1, 2, 3, 4, 5).iterator.indexWhere(_ == 2, 1)) + assertEquals(-1, List(1, 2, 3, 4, 5).iterator.indexWhere(_ == 2, 2)) + assertEquals(4, List(1, 2, 3, 2, 1).iterator.indexWhere(_ < 2, 1)) + assertEquals(1, List(1, 2, 3, 2, 1).iterator.indexWhere(_ <= 2, 1)) + } // iterator-iterate-lazy.scala // was java.lang.UnsupportedOperationException: tail of empty list @Test def iterateIsSufficientlyLazy(): Unit = { @@ -154,4 +168,12 @@ class IteratorTest { results += (Stream from 1).toIterator.drop(10).toStream.drop(10).toIterator.next() assertSameElements(List(1,1,21), results) } + // SI-8552 + @Test def indexOfShouldWorkForTwoParams(): Unit = { + assertEquals(1, List(1, 2, 3).iterator.indexOf(2, 0)) + assertEquals(-1, List(5 -> 0).iterator.indexOf(5, 0)) + assertEquals(0, List(5 -> 0).iterator.indexOf((5, 0))) + assertEquals(-1, List(5 -> 0, 9 -> 2, 0 -> 3).iterator.indexOf(9, 2)) + assertEquals(1, List(5 -> 0, 9 -> 2, 0 -> 3).iterator.indexOf(9 -> 2)) + } } |