t3418: non-interactive rebase --continue with rerere enabled

diff --git a/progress.c b/progress.c
index 412e6b1ecc36e8bd8b7f090b7da3dcf0c7e4e5bd..2e31bec60f5c98dc7dac69227759cbf2ba5f9974 100644 (file)
--- a/progress.c
+++ b/progress.c
@@ -72,6 +72,12 @@ static void clear_progress_signal(void)
        progress_update = 0;
 }
 
+static int is_foreground_fd(int fd)
+{
+       int tpgrp = tcgetpgrp(fd);
+       return tpgrp < 0 || tpgrp == getpgid(0);
+}
+
 static int display(struct progress *progress, unsigned n, const char *done)
 {
        const char *eol, *tp;
@@ -98,16 +104,21 @@ static int display(struct progress *progress, unsigned n, const char *done)
                unsigned percent = n * 100 / progress->total;
                if (percent != progress->last_percent || progress_update) {
                        progress->last_percent = percent;
-                       fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
-                               progress->title, percent, n,
-                               progress->total, tp, eol);
-                       fflush(stderr);
+                       if (is_foreground_fd(fileno(stderr)) || done) {
+                               fprintf(stderr, "%s: %3u%% (%u/%u)%s%s",
+                                       progress->title, percent, n,
+                                       progress->total, tp, eol);
+                               fflush(stderr);
+                       }
                        progress_update = 0;
                        return 1;
                }
        } else if (progress_update) {
-               fprintf(stderr, "%s: %u%s%s", progress->title, n, tp, eol);
-               fflush(stderr);
+               if (is_foreground_fd(fileno(stderr)) || done) {
+                       fprintf(stderr, "%s: %u%s%s",
+                               progress->title, n, tp, eol);
+                       fflush(stderr);
+               }
                progress_update = 0;
                return 1;
        }