# Good Git commit

Something about writing good git commit msgs.

### My favourite Git commit
<https://dhwthompson.com/2019/my-favourite-git-commit>

Git commit messages can tell us many things. Dan Carley wrote a good commit message about "[`Convert template to US-ASCII to fix error`](https://github.com/alphagov/govuk-puppet/commit/63b36f93bf75a848e2125008aa1e880c5861cf46)":

```log
I introduced some tests in a feature branch to match the contents of
`/etc/nginx/router_routes.conf`. They worked fine when run with `bundle exec
rake spec` or `bundle exec rspec modules/router/spec`. But when run as
`bundle exec rake` each should block failed with:

    ArgumentError:
      invalid byte sequence in US-ASCII

I eventually found that removing the `.with_content(//)` matchers made the
errors go away. That there weren't any weird characters in the spec file. And
that it could be reproduced by requiring Puppet in the same interpreter with:

    rake -E 'require "puppet"' spec

That particular template appears to be the only file in our codebase with an
identified encoding of `utf-8`. All others are `us-ascii`:

    dcarley-MBA:puppet dcarley$ find modules -type f -exec file --mime {} \+ | grep utf
    modules/router/templates/routes.conf.erb:                                         text/plain; charset=utf-8

Attempting to convert that file back to US-ASCII identified the offending
character as something that looked like a whitespace:

    dcarley-MBA:puppet dcarley$ iconv -f UTF8 -t US-ASCII modules/router/templates/routes.conf.erb 2>&1 | tail -n5
      proxy_intercept_errors off;

      # Set proxy timeout to 50 seconds as a quick fix for problems
      #
    iconv: modules/router/templates/routes.conf.erb:458:3: cannot convert

After replacing it (by hand) the file identifies as `us-ascii` again:

    dcarley-MBA:puppet dcarley$ file --mime modules/router/templates/routes.conf.erb
    modules/router/templates/routes.conf.erb: text/plain; charset=us-ascii

Now the tests work! One hour of my life I won't get back..
```

Write a commit is to comunicate, is to get work done and tell people about it.

### [Telling stories through your commits](https://blog.mocoso.co.uk/talks/2015/01/12/telling-stories-through-your-commits/)
1. Make atomic commits.
2. Write good commit messages.
3. Revise your development history before sharing


相关：[[git-edit-specific-commit-message|git-edit-specific-commit-message]]