Bug 14589 - mono Array.FindLastIndex is not equal to .NET Array.FindLastIndex
Summary: mono Array.FindLastIndex is not equal to .NET Array.FindLastIndex
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2013-09-10 05:13 UTC by Kirill
Modified: 2013-09-11 03:23 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Kirill 2013-09-10 05:13:08 UTC
Hello! I found difference in behavior of function Array.FindLastIndex

.Net code looking for item from startIndex to 0
mono code looking for item from last index to startIndex

mono code:
public static int FindLastIndex<T> (T [] array, int startIndex, int count, Predicate<T> match)
    for (int i = startIndex + count - 1; i >= startIndex; i--)
	if (match (array [i]))
		return i;
    return -1;

.NET code:

public static int FindLastIndex<T>(T[] array, int startIndex, int count, Predicate<T> match) {
    int endIndex = startIndex - count;
    for( int i = startIndex; i > endIndex; i--) {
        if( match(array[i])) {
           return i;
    return -1;
Comment 1 Marek Safar 2013-09-10 05:25:08 UTC
Please don't paste code from .net framework!
Comment 2 Kirill 2013-09-10 05:31:51 UTC
ok, but why it's resolved? )
Comment 3 Marek Safar 2013-09-10 06:16:19 UTC
Because it's invalid, we don't want bug reports with proprietary source code
Comment 4 Kirill 2013-09-11 03:23:06 UTC
sorry. I created a new issue