StackOverflow2013

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POObjective-C: Why this function name caused a warning?
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copied!<p>This is the original header file:</p> <pre><code>@interface TestDataHelper : NSObject { } +(void) populateTestData:(NSManagedObjectContext*) managedObjectContext; +(void) testPopulateTestData:(NSManagedObjectContext*) managedObjectContext; @end </code></pre> <p>When I compile this file, I got this warning:</p> <p><code>method definiton not found</code></p> <p>for testPopulateTestData</p> <p>When I ignore the warning and run the app in iphone simulator, I got a runtime exception:</p> <p><code>*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '+[TestDataHelper testPopulateTestData:]: unrecognized selector sent to class 0x104d8'</code></p> <p>Rename the method to 'test' alone seems to solve the problem</p> <p>What is special about <code>testXXX</code> method name?</p> <p><strong>EDIT:</strong> implementation is there and done. Renaming the method name (in both .h and .m) removes the warning, and the final app works.</p> <p><strong>EDIT 2</strong>:</p> <p>Here is the implementation of the function <code>test</code> (originally named as <code>testPopulatedTestData</code>):</p> <pre><code>+(void) test:(NSManagedObjectContext*) managedObjectContext { NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Stock" inManagedObjectContext:managedObjectContext]; [request setEntity:entity]; NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; [sortDescriptors release]; [sortDescriptor release]; NSError *error = nil; NSMutableArray *mutableFetchResults = [[managedObjectContext executeFetchRequest:request error:&error] mutableCopy]; NSEnumerator *e = [mutableFetchResults objectEnumerator]; id object; while (object = [e nextObject]) { // do something with object Stock* fc = (Stock*) object; NSLog(@"get a fc %s", [[fc name] description]); } } </code></pre>

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