prune-packed: avoid implying "1" is DRY_RUN in prune_packed_objects()

diff --git a/builtin/apply.c b/builtin/apply.c
index f6a3c97dd5903a8b7d42383da370428067c3e14e..30eefc3c7b390800e9452a06da18208d2fef4f11 100644 (file)
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -2117,10 +2117,10 @@ static void update_pre_post_images(struct image *preimage,
 
        /*
         * Adjust the common context lines in postimage. This can be
-        * done in-place when we are just doing whitespace fixing,
-        * which does not make the string grow, but needs a new buffer
-        * when ignoring whitespace causes the update, since in this case
-        * we could have e.g. tabs converted to multiple spaces.
+        * done in-place when we are shrinking it with whitespace
+        * fixing, but needs a new buffer when ignoring whitespace or
+        * expanding leading tabs to spaces.
+        *
         * We trust the caller to tell us if the update can be done
         * in place (postlen==0) or not.
         */
@@ -2185,7 +2185,7 @@ static int match_fragment(struct image *img,
        int i;
        char *fixed_buf, *buf, *orig, *target;
        struct strbuf fixed;
-       size_t fixed_len;
+       size_t fixed_len, postlen;
        int preimage_limit;
 
        if (preimage->nr + try_lno <= img->nr) {
@@ -2335,6 +2335,7 @@ static int match_fragment(struct image *img,
        strbuf_init(&fixed, preimage->len + 1);
        orig = preimage->buf;
        target = img->buf + try;
+       postlen = 0;
        for (i = 0; i < preimage_limit; i++) {
                size_t oldlen = preimage->line[i].len;
                size_t tgtlen = img->line[try_lno + i].len;
@@ -2362,6 +2363,7 @@ static int match_fragment(struct image *img,
                match = (tgtfix.len == fixed.len - fixstart &&
                         !memcmp(tgtfix.buf, fixed.buf + fixstart,
                                             fixed.len - fixstart));
+               postlen += tgtfix.len;
 
                strbuf_release(&tgtfix);
                if (!match)
@@ -2399,8 +2401,10 @@ static int match_fragment(struct image *img,
         * hunk match.  Update the context lines in the postimage.
         */
        fixed_buf = strbuf_detach(&fixed, &fixed_len);
+       if (postlen < postimage->len)
+               postlen = 0;
        update_pre_post_images(preimage, postimage,
-                              fixed_buf, fixed_len, 0);
+                              fixed_buf, fixed_len, postlen);
        return 1;
 
  unmatch_exit: