Custom type called twice with prompt about click HOT 2 CLOSED

Hello @davidism , just my 2 cents here: you're mentioning this issue as duplicate of 2 others, which means that several developers ended up with a use case of using a callback & prompt, while your answer consistently is "known behaviour". Wouldn't be a great idea to add a warning or so in the documentation so that we spend less time trying to get a clue on what's going on?

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Duplicate of #2662
Duplicate of #2259

This is due to how the processing pipeline works. Since the value wasn't given, it's prompted for. The prompt calls the callback to ensure the user typed a valid value before continuing (otherwise it keeps prompting). Then the value continues through the processing pipeline, which calls the callback (regardless of source) to validate the option before passing it to the command.

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