fetch-pack: eliminate spurious error messages

diff --git a/builtin/read-tree.c b/builtin/read-tree.c
index 8bdcab11389e8b4facab355f27f0e1926134b86f..042ac1b84f22257d1a8a4d32d34124b6dc372f16 100644 (file)
--- a/builtin/read-tree.c
+++ b/builtin/read-tree.c
@@ -16,6 +16,7 @@
 #include "resolve-undo.h"
 
 static int nr_trees;
+static int read_empty;
 static struct tree *trees[MAX_UNPACK_TREES];
 
 static int list_tree(unsigned char *sha1)
@@ -32,7 +33,7 @@ static int list_tree(unsigned char *sha1)
 }
 
 static const char * const read_tree_usage[] = {
-       "git read-tree [[-m [--trivial] [--aggressive] | --reset | --prefix=<prefix>] [-u [--exclude-per-directory=<gitignore>] | -i]] [--no-sparse-checkout] [--index-output=<file>] <tree-ish1> [<tree-ish2> [<tree-ish3>]]",
+       N_("git read-tree [[-m [--trivial] [--aggressive] | --reset | --prefix=<prefix>] [-u [--exclude-per-directory=<gitignore>] | -i]] [--no-sparse-checkout] [--index-output=<file>] (--empty | <tree-ish1> [<tree-ish2> [<tree-ish3>]])"),
        NULL
 };
 
@@ -103,34 +104,37 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
        struct unpack_trees_options opts;
        int prefix_set = 0;
        const struct option read_tree_options[] = {
-               { OPTION_CALLBACK, 0, "index-output", NULL, "FILE",
-                 "write resulting index to <FILE>",
+               { OPTION_CALLBACK, 0, "index-output", NULL, N_("file"),
+                 N_("write resulting index to <file>"),
                  PARSE_OPT_NONEG, index_output_cb },
-               OPT__VERBOSE(&opts.verbose_update),
-               OPT_GROUP("Merging"),
+               OPT_SET_INT(0, "empty", &read_empty,
+                           N_("only empty the index"), 1),
+               OPT__VERBOSE(&opts.verbose_update, N_("be verbose")),
+               OPT_GROUP(N_("Merging")),
                OPT_SET_INT('m', NULL, &opts.merge,
-                           "perform a merge in addition to a read", 1),
+                           N_("perform a merge in addition to a read"), 1),
                OPT_SET_INT(0, "trivial", &opts.trivial_merges_only,
-                           "3-way merge if no file level merging required", 1),
+                           N_("3-way merge if no file level merging required"), 1),
                OPT_SET_INT(0, "aggressive", &opts.aggressive,
-                           "3-way merge in presence of adds and removes", 1),
+                           N_("3-way merge in presence of adds and removes"), 1),
                OPT_SET_INT(0, "reset", &opts.reset,
-                           "same as -m, but discard unmerged entries", 1),
-               { OPTION_STRING, 0, "prefix", &opts.prefix, "<subdirectory>/",
-                 "read the tree into the index under <subdirectory>/",
+                           N_("same as -m, but discard unmerged entries"), 1),
+               { OPTION_STRING, 0, "prefix", &opts.prefix, N_("<subdirectory>/"),
+                 N_("read the tree into the index under <subdirectory>/"),
                  PARSE_OPT_NONEG | PARSE_OPT_LITERAL_ARGHELP },
                OPT_SET_INT('u', NULL, &opts.update,
-                           "update working tree with merge result", 1),
+                           N_("update working tree with merge result"), 1),
                { OPTION_CALLBACK, 0, "exclude-per-directory", &opts,
-                 "gitignore",
-                 "allow explicitly ignored files to be overwritten",
+                 N_("gitignore"),
+                 N_("allow explicitly ignored files to be overwritten"),
                  PARSE_OPT_NONEG, exclude_per_directory_cb },
                OPT_SET_INT('i', NULL, &opts.index_only,
-                           "don't check the working tree after merging", 1),
+                           N_("don't check the working tree after merging"), 1),
+               OPT__DRY_RUN(&opts.dry_run, N_("don't update the index or the work tree")),
                OPT_SET_INT(0, "no-sparse-checkout", &opts.skip_sparse_checkout,
-                           "skip applying sparse checkout filter", 1),
+                           N_("skip applying sparse checkout filter"), 1),
                OPT_SET_INT(0, "debug-unpack", &opts.debug_unpack,
-                           "debug unpack-trees", 1),
+                           N_("debug unpack-trees"), 1),
                OPT_END()
        };
 
@@ -166,6 +170,11 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
                        die("failed to unpack tree object %s", arg);
                stage++;
        }
+       if (nr_trees == 0 && !read_empty)
+               warning("read-tree: emptying the index with no arguments is deprecated; use --empty");
+       else if (nr_trees > 0 && read_empty)
+               die("passing trees as arguments contradicts --empty");
+
        if (1 < opts.index_only + opts.update)
                die("-u and -i at the same time makes no sense");
        if ((opts.update||opts.index_only) && !opts.merge)
@@ -211,7 +220,7 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
        if (unpack_trees(nr_trees, t, &opts))
                return 128;
 
-       if (opts.debug_unpack)
+       if (opts.debug_unpack || opts.dry_run)
                return 0; /* do not write the index out */
 
        /*
@@ -219,14 +228,9 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
         * "-m ent" or "--reset ent" form), we can obtain a fully
         * valid cache-tree because the index must match exactly
         * what came from the tree.
-        *
-        * The same holds true if we are switching between two trees
-        * using read-tree -m A B.  The index must match B after that.
         */
        if (nr_trees == 1 && !opts.prefix)
                prime_cache_tree(&active_cache_tree, trees[0]);
-       else if (nr_trees == 2 && opts.merge)
-               prime_cache_tree(&active_cache_tree, trees[1]);
 
        if (write_cache(newfd, active_cache, active_nr) ||
            commit_locked_index(&lock_file))