bugGNUSTEP System - Bugs: bug #19220, NSArray containsObject: and...


bug #19220: NSArray containsObject: and indexOfObject: do not invoke isEqual on array element

Submitted by:  Jonathan Olson <jpolson>
Submitted on:  Tue 06 Mar 2007 04:36:52 PM UTC  
Category: NoneSeverity: 3 - Normal
Item Group: NoneStatus: None
Privacy: PublicAssigned to: None
Open/Closed: Open

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Tue 06 Mar 2007 04:36:52 PM UTC, original submission:

The NSArray class has a subtle incompatiblity with the Foundation class on Cocoa.
According to the Apple OSX documentation for containsObject:

This method determines whether anObject is present in the receiver by sending an isEqual: message to each of the receiver’s objects (and passing anObject as the parameter to each isEqual: message).

However, the GNUstep implementation instead invokes the isEqual: method on the parameter, passing the array element as the parameter to isEqual:. This causes subtle incompatibilities in applications which implement non-commutative isEqual: methods.

Attached is a test program illustrating this behavior. On OSX, this program returns YES for both containsObject: comparisons.

Jonathan Olson <jpolson>


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Attach File(s):

Attached Files
file #12129:  test.m added by jpolson (827B - application/octet-stream)


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    Follows 1 latest change.

    Date Changed By Updated Field Previous Value => Replaced By
    Tue 06 Mar 2007 04:36:52 PM UTCjpolsonAttached File-=>Added test.m, #12129

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