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Date:   Wed, 2 Jun 2021 15:37:10 -0400
From:   Jeff King <peff@peff.net>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     git@vger.kernel.org, Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Jiri Kosina <trivial@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: git feature request: git blame --ignore-cleanup/--ignore-trivial
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On Wed, Jun 02, 2021 at 11:20:35AM -0400, Mathieu Desnoyers wrote:

> Considering the added value brought by splitting cleanups from functional changes
> from a maintainer perspective (easier reverts) and from a reviewer perspective
> (easier to focus on the functional changes), I think it would be good to improve
> the git tooling to allow easily filtering out the noise from git blame.
> 
> Perhaps a new git blame "--ignore-trivial" and/or "--ignore-cleanup" could solve
> this by filtering out "trivial" and "cleanup" patches from the history it considers.

There's "-w" to ignore whitespace-only changes. Since Git v2.23.0,
there's also "--ignore-rev-file", which lets you ignore arbitrary
commits. Since you have to generate a separate list of commits to feed
it, it's a little more involved than your "--invert-grep" example. But
it's also much more flexible (you can generate the file however you
like, and even tweak it by hand).

I do tend to agree with Al's notion that commits which are _supposed_ to
be trivial sometimes end up not being so. Or another way of thinking
about it is: relevance is a property of the query you're making, not the
original change.

So IMHO the best tool for this kind of thing is the "re-blame from
parent" feature that many interactive blame viewers have (I use tig, but
I'm sure other tools like magic have a similar feature). There when you
land on a boring commit, it's a single key to skip past it and see how
the earlier code came about.

-Peff