[recent build based on 8a5f80ebb3dd]

I would expect that this (junit) test case would pass (File=java.io.File, FileUtil=org.openide.filesystems.FileUtil,IOException=java.io.IOException):
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public void testSomeMethod() throws IOException {
    File a = new File("C:\\a");
        
    a.delete();//so the test can be restarted
        
    assertTrue(a.createNewFile());
    File A = new File("C:\\A");
        
    assertEquals(a.getAbsolutePath(),FileUtil.normalizeFile(A).getAbsolutePath());
        
    assertTrue(A.delete());
        
    assertTrue(A.createNewFile());
        
    assertEquals(A.getAbsolutePath(),FileUtil.normalizeFile(A).getAbsolutePath());
}
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But it does not. Note that in the end the file that exists on disk is C:\A, but normalize file returns C:\a in this case, because it remembers the result of the first normalizeFile. If the first normalizeFile would not be called, the result of the second normalize file would be C:\A, which is correct, IMO. This leads into quite unpredictable behavior. Introduced by bug #183308.

I would expect that the FileUtil.normalizeFile would:
-not change the input cases for non-existing files
-return the exact cases as are on disk for existing files