From: Derrick Stolee <stolee@gmail.com>
Date: Tue, 15 Dec 2020 14:27:54 GMT
Subject: Re: [PATCH v2 10/11] merge-ort: add implementation of normal rename handling
Message-ID: <e7ce7008-0968-895c-f6e2-ee2609fd2556@gmail.com>
In-Reply-To: <22cb71102614f9d1fdd41a4b9524f11e08afa241.1607962900.git.gitgitgadget@gmail.com>

On 12/14/2020 11:21 AM, Elijah Newren via GitGitGadget wrote:
> From: Elijah Newren <newren@gmail.com>
> 
> Implement handling of normal renames.  This code replaces the following
> from merge-recurisve.c:
> 
>   * the code relevant to RENAME_NORMAL in process_renames()
>   * the RENAME_NORMAL case of process_entry()
> 
> Also, there is some shared code from merge-recursive.c for multiple
> different rename cases which we will no longer need for this case (or
> other rename cases):
> 
>   * handle_rename_normal()
>   * setup_rename_conflict_info()
> 
> The consolidation of four separate codepaths into one is made possible
> by a change in design: process_renames() tweaks the conflict_info
> entries within opt->priv->paths such that process_entry() can then
> handle all the non-rename conflict types (directory/file, modify/delete,
> etc.) orthogonally.  This means we're much less likely to miss special
> implementation of some kind of combination of conflict types (see
> commits brought in by 66c62eaec6 ("Merge branch 'en/merge-tests'",
> 2020-11-18), especially commit ef52778708 ("merge tests: expect improved
> directory/file conflict handling in ort", 2020-10-26) for more details).
> That, together with letting worktree/index updating be handled
> orthogonally in the merge_switch_to_result() function, dramatically
> simplifies the code for various special rename cases.
> 
> (To be fair, the code for handling normal renames wasn't all that
> complicated beforehand, but it's still much simpler now.)

Definitely looks simple.

> +				memcpy(&newinfo->stages[other_source_index],
> +				       &oldinfo->stages[other_source_index],
> +				       sizeof(newinfo->stages[0]));
> +				newinfo->filemask |= (1 << other_source_index);
> +				newinfo->pathnames[other_source_index] = oldpath;

I'm happy your organization brought us to a clean place.

Thanks,
-Stolee