apply: count the size of postimage correctly

diff --git a/builtin/apply.c b/builtin/apply.c
index da6fb355453c1a77d16a3ede38d295f5af8569d9..e8953404d2f1621fbb5d964b6b3adceed0ef74f6 100644 (file)
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -2336,6 +2336,23 @@ static int match_fragment(struct image *img,
         * ignore whitespace, we were asked to correct whitespace
         * errors, so let's try matching after whitespace correction.
         *
+        * While checking the preimage against the target, whitespace
+        * errors in both fixed, we count how large the corresponding
+        * postimage needs to be.  The postimage prepared by
+        * apply_one_fragment() has whitespace errors fixed on added
+        * lines already, but the common lines were propagated as-is,
+        * which may become longer when their whitespace errors are
+        * fixed.
+        */
+
+       /* First count added lines in postimage */
+       postlen = 0;
+       for (i = 0; i < postimage->nr; i++) {
+               if (!(postimage->line[i].flag & LINE_COMMON))
+                       postlen += postimage->line[i].len;
+       }
+
+       /*
         * The preimage may extend beyond the end of the file,
         * but in this loop we will only handle the part of the
         * preimage that falls within the file.
@@ -2343,7 +2360,6 @@ 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;
@@ -2371,7 +2387,10 @@ 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;
+
+               /* Add the length if this is common with the postimage */
+               if (preimage->line[i].flag & LINE_COMMON)
+                       postlen += tgtfix.len;
 
                strbuf_release(&tgtfix);
                if (!match)