From: Junio C Hamano Date: Tue, 02 May 2017 04:20:50 GMT Subject: Re: [RFC] [GSoC] Port git-add--interactive.perl:status_cmd to C Message-ID: In-Reply-To: Junio C Hamano writes: > "Daniel Ferreira (theiostream)" writes: > >> Reproducing either of these comparisons "natively" would simply >> require running run_diff_index() or run_diff_files() with >> DIFF_FORMAT_NUMSTAT and tweaking diff_flush() to format appropriately >> for the "interactive--add case". > > A more usual way to drive the diff machinery and react to its > findings is to use DIFF_FORMAT_CALLBACK interface, and walk the > collected diff_queue to work on the paths discovered. The way > wt-status.c builds "Changes to be committed" list out of the > "diff-index --cached" it internally runs and "Changes not staged for > commit" out of the "diff-files" it internally runs would be a good > example to study. Ahh, you'd also want to show the numstat equivalent and eventually you'd need to spool the actual textual diff in-core, so that you can present hunks to the user and have them accepted/rejected interactively. CALLBACK interface is not a good match for that task. Of course, using a temporary file to buffer output from diff would be an obvious and simple workaround (and this is not a performance critical part of the system---we are talking about end user choosing hunks interactively after all). A cleaner may be to spawn diff-index and diff-files and read from them via pipe into core.