PR Summary

Currently, the formatter uses WriteLine() on the content expecting it to be not empty. If the custom format explicitly doesn't write anything, it ends up as a newline. Fix is to check that there is something to write, otherwise bail out early. With this change, an empty string still results in a newline, but $null skips writing the newline.

PR Context

Affects a custom formatter I'm writing that requires output to not have trailing newlines.

PR Checklist

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