[Kimchi-devel] Improving diff hunk headers

[Sheldon]

On 05/21/2014 12:25 AM, Christy Perez wrote:
> Hi all,
>
> I was looking over patches today and wished that there was better
> context for the changed lines. Specifically, I wanted a function name
> instead of just the class name.
>
> I finally came across this e-mail [1] from someone at Red Hat:
>
> """
> Hello,
>
> I'm sure you're aware of hunk header lines in patches:
>      @@ -24,5 +24,5 @@ class SomeClass(object):
>
>
> It's possible to configure which source line Git selects for the hunk
> header. By default it uses non-indented lines. A "python" regexp, which
> selects functions, classes and methods, is already included in Git; you
> just have to enable it. I also use custom regexps for ldifs and API.txt:
>
>
>
> $ cat ~/.gitattributes # (Or .git/info/attributes for project-specific
> config)
>
> *.py diff=python
> API.txt diff=apitxt
> *.ldif diff=ldif
> *.update diff=ldif
>
>
> $ git config -l  # set with e.g. `git config --global key="value"`
> ...
> core.attributesfile=~/.gitattributes
> diff.apitxt.xfuncname=^command: .*
> diff.ldif.xfuncname=^dn:.*
>
>
> Enjoy your Friday!
>
> --
> Petr³
> """
>
> We can also define our own, as per:
> http://stackoverflow.com/questions/2783086/how-does-git-diff-generate-hunk-descriptions
>
> I put *.py diff=python into my kimchi project's .git/info/attributes
> file, and I like these diffs a lot better.
>
> For example (using a really old branch I should have deleted while ago!
> ):
>
> @@ -37,7 +37,6 @@ class AsyncTask(object):
>           self.status = 'running'
>           self.message = 'OK'
>           self._save_helper()
> -        self._cp_request = cherrypy.serving.request
>           self.thread = threading.Thread(target=self._run_helper,
>                                          args=(opaque, self._status_cb))
>           self.thread.setDaemon(True)
> @@ -37,7 +37,6 @@ class AsyncTask(object):
>           self.status = 'running'
>           self.message = 'OK'
>           self._save_helper()
> -        self._cp_request = cherrypy.serving.request
>           self.thread = threading.Thread(target=self._run_helper,
>                                          args=(opaque, self._status_cb))
>           self.thread.setDaemon(True)
> @@ -60,17 +59,13 @@ class AsyncTask(object):
>           obj = {}
>           for attr in ('id', 'target_uri', 'message', 'status'):
>               obj[attr] = getattr(self, attr)
> -        try:
> -            with self.objstore as session:
> -                session.store('task', self.id, obj)
> -        except Exception as e:
> -            raise OperationFailed('KCHASYNC0002E', {'err': e.message})
> +        with self.objstore as session:
> +            session.store('task', self.id, obj)
>   
>       def _run_helper(self, opaque, cb):
> -        cherrypy.serving.request = self._cp_request
>           try:
>
> changes to:
>
> diff --git a/src/kimchi/asynctask.py b/src/kimchi/asynctask.py
> index e2d2dcf..8f0d96c 100644
> --- a/src/kimchi/asynctask.py
> +++ b/src/kimchi/asynctask.py
> @@ -37,7 +37,6 @@ def __init__(self, id, target_uri, fn, objstore,
> opaque=None):
>           self.status = 'running'
>           self.message = 'OK'
>           self._save_helper()
> -        self._cp_request = cherrypy.serving.request
>           self.thread = threading.Thread(target=self._run_helper,
>                                          args=(opaque, self._status_cb))
>           self.thread.setDaemon(True)
> @@ -60,17 +59,13 @@ def _save_helper(self):
seems it is good to show  the function _save_helper(self) instead of 
class AsyncTask(object)
>           obj = {}
>           for attr in ('id', 'target_uri', 'message', 'status'):
>               obj[attr] = getattr(self, attr)
> -        try:
> -            with self.objstore as session:
> -                session.store('task', self.id, obj)
> -        except Exception as e:
> -            raise OperationFailed('KCHASYNC0002E', {'err': e.message})
> +        with self.objstore as session:
>
> So now you can see the function that the code is in, not the
> larger-scope (the class).
>
> I thought I would share, in case any one else wanted to use this.
>
> Maybe we could even add a .gitattributes file to kimchi if others think
> it's a good idea to enforce some project-specific conventions.
>
> Happy coding!
>
> - Christy
>
> [1]
> http://www.redhat.com/archives/freeipa-devel/2013-April/msg00381.html
>
> _______________________________________________
> Kimchi-devel mailing list
> Kimchi-devel at ovirt.org
> http://lists.ovirt.org/mailman/listinfo/kimchi-devel


-- 
Thanks and best regards!

Sheldon Feng(冯少合)<shaohef at linux.vnet.ibm.com>
IBM Linux Technology Center