[RFC/PATCH 4/4] inexact rename detection eye candy

[Jeff King <peff@peff.net>]

During a merge, we might spend many seconds doing inexact
rename detection. It's nice to let the user know that
something is actually happening.

Signed-off-by: Jeff King <peff@peff.net>
---
This feels wrong because it's in such a deep library function. At the
very least we probably need some way to turn it off, so callers can pass
along any --quiet or --no-progress indicators. Though I think it should
perhaps be off entirely for any revision traversals (since the progress
will be per-commit, so it will be in the middle of log output). And then
on for diff (unless --quiet is given), and on for merge.

I made it update progress for each of the rename_src * rename_dst
similarity estimates. We could just as easily count rename_dst items we
look at, but hey, it's eye candy, and obviously bigger numbers are
better.

 diffcore-rename.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/diffcore-rename.c b/diffcore-rename.c
index 1d3d5cd..136a86f 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -5,6 +5,7 @@
 #include "diff.h"
 #include "diffcore.h"
 #include "hash.h"
+#include "progress.h"
 
 /* Table of rename/copy destinations */
 
@@ -449,6 +450,7 @@ void diffcore_rename(struct diff_options *options)
 	struct diff_score *mx;
 	int i, j, rename_count;
 	int num_create, num_src, dst_cnt;
+	struct progress *progress;
 
 	if (!minimum_score)
 		minimum_score = DEFAULT_RENAME_SCORE;
@@ -528,6 +530,10 @@ void diffcore_rename(struct diff_options *options)
 		goto cleanup;
 	}
 
+	progress = start_progress_delay(
+			"Performing inexact rename detection",
+			rename_dst_nr * rename_src_nr, 50, 1);
+
 	mx = xcalloc(num_create * NUM_CANDIDATE_PER_DST, sizeof(*mx));
 	for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
 		struct diff_filespec *two = rename_dst[i].two;
@@ -555,9 +561,11 @@ void diffcore_rename(struct diff_options *options)
 			 */
 			diff_free_filespec_blob(one);
 			diff_free_filespec_blob(two);
+			display_progress(progress, i*rename_src_nr + j);
 		}
 		dst_cnt++;
 	}
+	stop_progress(&progress);
 
 	/* cost matrix sorted by most to least similar pair */
 	qsort(mx, dst_cnt * NUM_CANDIDATE_PER_DST, sizeof(*mx), score_compare);
-- 
1.7.4.1.26.g5e991