t: add test harness for external credential helpers

diff --git a/xdiff/xemit.c b/xdiff/xemit.c
index 64eb17a46387e0dc5e19b5c4901433c4c6fe4fab..2e669c3e2570332ee50a72e06a77ad4a356ecfd6 100644 (file)
--- a/xdiff/xemit.c
+++ b/xdiff/xemit.c
@@ -105,22 +105,27 @@ struct func_line {
        char buf[80];
 };
 
-static void get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
+static long get_func_line(xdfenv_t *xe, xdemitconf_t const *xecfg,
                          struct func_line *func_line, long start, long limit)
 {
        find_func_t ff = xecfg->find_func ? xecfg->find_func : def_ff;
-       long l, size = sizeof(func_line->buf);
-       char *buf = func_line->buf;
+       long l, size, step = (start > limit) ? -1 : 1;
+       char *buf, dummy[1];
 
-       for (l = start; l > limit && 0 <= l; l--) {
+       buf = func_line ? func_line->buf : dummy;
+       size = func_line ? sizeof(func_line->buf) : sizeof(dummy);
+
+       for (l = start; l != limit && 0 <= l && l < xe->xdf1.nrec; l += step) {
                const char *rec;
                long reclen = xdl_get_rec(&xe->xdf1, l, &rec);
                long len = ff(rec, reclen, buf, size, xecfg->find_func_priv);
                if (len >= 0) {
-                       func_line->len = len;
-                       break;
+                       if (func_line)
+                               func_line->len = len;
+                       return l;
                }
        }
+       return -1;
 }
 
 int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
@@ -139,6 +144,17 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
                s1 = XDL_MAX(xch->i1 - xecfg->ctxlen, 0);
                s2 = XDL_MAX(xch->i2 - xecfg->ctxlen, 0);
 
+               if (xecfg->flags & XDL_EMIT_FUNCCONTEXT) {
+                       long fs1 = get_func_line(xe, xecfg, NULL, xch->i1, -1);
+                       if (fs1 < 0)
+                               fs1 = 0;
+                       if (fs1 < s1) {
+                               s2 -= s1 - fs1;
+                               s1 = fs1;
+                       }
+               }
+
+ again:
                lctx = xecfg->ctxlen;
                lctx = XDL_MIN(lctx, xe->xdf1.nrec - (xche->i1 + xche->chg1));
                lctx = XDL_MIN(lctx, xe->xdf2.nrec - (xche->i2 + xche->chg2));
@@ -146,6 +162,32 @@ int xdl_emit_diff(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
                e1 = xche->i1 + xche->chg1 + lctx;
                e2 = xche->i2 + xche->chg2 + lctx;
 
+               if (xecfg->flags & XDL_EMIT_FUNCCONTEXT) {
+                       long fe1 = get_func_line(xe, xecfg, NULL,
+                                                xche->i1 + xche->chg1,
+                                                xe->xdf1.nrec);
+                       if (fe1 < 0)
+                               fe1 = xe->xdf1.nrec;
+                       if (fe1 > e1) {
+                               e2 += fe1 - e1;
+                               e1 = fe1;
+                       }
+
+                       /*
+                        * Overlap with next change?  Then include it
+                        * in the current hunk and start over to find
+                        * its new end.
+                        */
+                       if (xche->next) {
+                               long l = xche->next->i1;
+                               if (l <= e1 ||
+                                   get_func_line(xe, xecfg, NULL, l, e1) < 0) {
+                                       xche = xche->next;
+                                       goto again;
+                               }
+                       }
+               }
+
                /*
                 * Emit current hunk header.
                 */