ui.write: don't clear progress bar when writing to a buffer ui.write() has 2 modes: buffered and unbuffered. In buffered mode, we capture output before writing it. This is how changeset printing works, for example. Previously, we were potentially clearing the progress bar for every call to ui.write(). In buffered mode, this clearing was useless because the clearing function would be called again before actually writing the buffered data. This patch stops the useless calling of _progclear() unless we are actually writing data. During changeset printing with the default template, this removes ~6 function calls per changeset, making changeset printing slightly faster. before: 23.76s after: 23.35s delta: -0.41s (98.3% of original)