I want to test that my Cocoa app properly handles input outside the basic multilingual plane, and copy-pasting it is out of the question. I don't know how to key in a character outside BMP! I have set up Japanese as an input source and am able to get random Katakana or Hiragana by typing Japanese-sounding words, but that trick won't work for plane 2 characters. Pasting characters in dismisses the input method editor, so that doesn't work either. I think I actually need to enter the correct keystrokes on my US English keyboard into some language's input source (Chinese, presumably, would be a good choice). In case it's not obvious, I don't speak any Asian languages.
Here's an example of some characters in the second plane: http://www.unicode.org/cgi-bin/UnihanGrid.pl?codepoint=20000
Any unicode character above 0xffff would be acceptable for my purposes as long as I can render the glyph with a font I have or can get for free.