t/test-lib.sh: add test_external and test_external_without_stderr

diff --git a/builtin-show-ref.c b/builtin-show-ref.c
index 75211e64f9a850be95de3b85edaafdf0d9a5886a..a323633e296cef1797ab1d218cea83c891bc3b8d 100644 (file)
--- a/builtin-show-ref.c
+++ b/builtin-show-ref.c
@@ -1,3 +1,4 @@
+#include "builtin.h"
 #include "cache.h"
 #include "refs.h"
 #include "object.h"
@@ -28,8 +29,8 @@ static int show_ref(const char *refname, const unsigned char *sha1, int flag, vo
        if (tags_only || heads_only) {
                int match;
 
-               match = heads_only && !strncmp(refname, "refs/heads/", 11);
-               match |= tags_only && !strncmp(refname, "refs/tags/", 10);
+               match = heads_only && !prefixcmp(refname, "refs/heads/");
+               match |= tags_only && !prefixcmp(refname, "refs/tags/");
                if (!match)
                        return 0;
        }
@@ -85,6 +86,9 @@ static int show_ref(const char *refname, const unsigned char *sha1, int flag, vo
                            sha1_to_hex(sha1));
                if (obj->type == OBJ_TAG) {
                        obj = deref_tag(obj, refname, 0);
+                       if (!obj)
+                               die("git-show-ref: bad tag at ref %s (%s)", refname,
+                                   sha1_to_hex(sha1));
                        hex = find_unique_abbrev(obj->sha1, abbrev);
                        printf("%s %s^{}\n", hex, refname);
                }
@@ -178,8 +182,8 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix)
                        hash_only = 1;
                        continue;
                }
-               if (!strncmp(arg, "--hash=", 7) ||
-                   (!strncmp(arg, "--abbrev", 8) &&
+               if (!prefixcmp(arg, "--hash=") ||
+                   (!prefixcmp(arg, "--abbrev") &&
                     (arg[8] == '=' || arg[8] == '\0'))) {
                        if (arg[2] != 'h' && !arg[8])
                                /* --abbrev only */
@@ -215,7 +219,7 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix)
                }
                if (!strcmp(arg, "--exclude-existing"))
                        return exclude_existing(NULL);
-               if (!strncmp(arg, "--exclude-existing=", 19))
+               if (!prefixcmp(arg, "--exclude-existing="))
                        return exclude_existing(arg + 19);
                usage(show_ref_usage);
        }
@@ -226,7 +230,7 @@ int cmd_show_ref(int argc, const char **argv, const char *prefix)
                while (*pattern) {
                        unsigned char sha1[20];
 
-                       if (!strncmp(*pattern, "refs/", 5) &&
+                       if (!prefixcmp(*pattern, "refs/") &&
                            resolve_ref(*pattern, sha1, 1, NULL)) {
                                if (!quiet)
                                        show_one(*pattern, sha1);