Merge branch 'jc/maint-1.6.1-checkout-m-custom-merge' into maint
[git/git.git] / builtin-checkout.c
index e41e73b..67229fc 100644 (file)
@@ -5,6 +5,7 @@
 #include "commit.h"
 #include "tree.h"
 #include "tree-walk.h"
+#include "cache-tree.h"
 #include "unpack-trees.h"
 #include "dir.h"
 #include "run-command.h"
@@ -38,23 +39,13 @@ struct checkout_opts {
 static int post_checkout_hook(struct commit *old, struct commit *new,
                              int changed)
 {
-       struct child_process proc;
-       const char *name = git_path("hooks/post-checkout");
-       const char *argv[5];
+       return run_hook(NULL, "post-checkout",
+                       sha1_to_hex(old ? old->object.sha1 : null_sha1),
+                       sha1_to_hex(new ? new->object.sha1 : null_sha1),
+                       changed ? "1" : "0", NULL);
+       /* "new" can be NULL when checking out from the index before
+          a commit exists. */
 
-       if (access(name, X_OK) < 0)
-               return 0;
-
-       memset(&proc, 0, sizeof(proc));
-       argv[0] = name;
-       argv[1] = xstrdup(sha1_to_hex(old ? old->object.sha1 : null_sha1));
-       argv[2] = xstrdup(sha1_to_hex(new->object.sha1));
-       argv[3] = changed ? "1" : "0";
-       argv[4] = NULL;
-       proc.argv = argv;
-       proc.no_stdin = 1;
-       proc.stdout_to_stderr = 1;
-       return run_command(&proc);
 }
 
 static int update_some(const unsigned char *sha1, const char *base, int baselen,
@@ -63,9 +54,6 @@ static int update_some(const unsigned char *sha1, const char *base, int baselen,
        int len;
        struct cache_entry *ce;
 
-       if (S_ISGITLINK(mode))
-               return 0;
-
        if (S_ISDIR(mode))
                return READ_TREE_RECURSIVE;
 
@@ -191,7 +179,7 @@ static int checkout_merged(int pos, struct checkout *state)
        /*
         * NEEDSWORK:
         * There is absolutely no reason to write this as a blob object
-        * and create a phoney cache entry just to leak.  This hack is
+        * and create a phony cache entry just to leak.  This hack is
         * primarily to get to the write_entry() machinery that massages
         * the contents to work-tree format and writes out which only
         * allows it for a cache entry.  The code in write_entry() needs
@@ -228,7 +216,8 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
 
        newfd = hold_locked_index(lock_file, 1);
-       read_cache();
+       if (read_cache_preload(pathspec) < 0)
+               return error("corrupt index file");
 
        if (source_tree)
                read_tree_some(source_tree, pathspec);
@@ -239,7 +228,7 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
 
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
-               pathspec_match(pathspec, ps_matched, ce->name, 0);
+               match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched);
        }
 
        if (report_path_error(ps_matched, pathspec, 0))
@@ -248,7 +237,7 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
        /* Any unmerged paths? */
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
-               if (pathspec_match(pathspec, NULL, ce->name, 0)) {
+               if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
                        if (!ce_stage(ce))
                                continue;
                        if (opts->force) {
@@ -273,7 +262,7 @@ static int checkout_paths(struct tree *source_tree, const char **pathspec,
        state.refresh_cache = 1;
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
-               if (pathspec_match(pathspec, NULL, ce->name, 0)) {
+               if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
                        if (!ce_stage(ce)) {
                                errs |= checkout_entry(ce, &state, NULL);
                                continue;
@@ -304,6 +293,8 @@ static void show_local_changes(struct object *head)
        init_revisions(&rev, NULL);
        rev.abbrev = 0;
        rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
+       if (diff_setup_done(&rev.diffopt) < 0)
+               die("diff_setup_done failed");
        add_pending_object(&rev, head, NULL);
        run_diff_index(&rev, 0);
 }
@@ -311,8 +302,9 @@ static void show_local_changes(struct object *head)
 static void describe_detached_head(char *msg, struct commit *commit)
 {
        struct strbuf sb = STRBUF_INIT;
+       struct pretty_print_context ctx = {0};
        parse_commit(commit);
-       pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, 0, NULL, NULL, 0, 0);
+       pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, &ctx);
        fprintf(stderr, "%s %s... %s\n", msg,
                find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
        strbuf_release(&sb);
@@ -360,8 +352,11 @@ struct branch_info {
 static void setup_branch_path(struct branch_info *branch)
 {
        struct strbuf buf = STRBUF_INIT;
-       strbuf_addstr(&buf, "refs/heads/");
-       strbuf_addstr(&buf, branch->name);
+
+       strbuf_branchname(&buf, branch->name);
+       if (strcmp(buf.buf, branch->name))
+               branch->name = xstrdup(buf.buf);
+       strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
        branch->path = strbuf_detach(&buf, NULL);
 }
 
@@ -371,7 +366,9 @@ static int merge_working_tree(struct checkout_opts *opts,
        int ret;
        struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
        int newfd = hold_locked_index(lock_file, 1);
-       read_cache();
+
+       if (read_cache_preload(NULL) < 0)
+               return error("corrupt index file");
 
        if (opts->force) {
                ret = reset_tree(new->commit->tree, opts, 1);
@@ -400,13 +397,15 @@ static int merge_working_tree(struct checkout_opts *opts,
                topts.initial_checkout = is_cache_unborn();
                topts.update = 1;
                topts.merge = 1;
-               topts.gently = opts->merge;
+               topts.gently = opts->merge && old->commit;
                topts.verbose_update = !opts->quiet;
                topts.fn = twoway_merge;
                topts.dir = xcalloc(1, sizeof(*topts.dir));
-               topts.dir->show_ignored = 1;
+               topts.dir->flags |= DIR_SHOW_IGNORED;
                topts.dir->exclude_per_dir = ".gitignore";
-               tree = parse_tree_indirect(old->commit->object.sha1);
+               tree = parse_tree_indirect(old->commit ?
+                                          old->commit->object.sha1 :
+                                          (unsigned char *)EMPTY_TREE_SHA1_BIN);
                init_tree_desc(&trees[0], tree->buffer, tree->size);
                tree = parse_tree_indirect(new->commit->object.sha1);
                init_tree_desc(&trees[1], tree->buffer, tree->size);
@@ -423,7 +422,13 @@ static int merge_working_tree(struct checkout_opts *opts,
                        struct merge_options o;
                        if (!opts->merge)
                                return 1;
-                       parse_commit(old->commit);
+
+                       /*
+                        * Without old->commit, the below is the same as
+                        * the two-tree unpack we already tried and failed.
+                        */
+                       if (!old->commit)
+                               return 1;
 
                        /* Do more real merge */
 
@@ -500,10 +505,10 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                create_symref("HEAD", new->path, msg.buf);
                if (!opts->quiet) {
                        if (old->path && !strcmp(new->path, old->path))
-                               fprintf(stderr, "Already on \"%s\"\n",
+                               fprintf(stderr, "Already on '%s'\n",
                                        new->name);
                        else
-                               fprintf(stderr, "Switched to%s branch \"%s\"\n",
+                               fprintf(stderr, "Switched to%s branch '%s'\n",
                                        opts->new_branch ? " a new" : "",
                                        new->name);
                }
@@ -512,7 +517,7 @@ static void update_refs_for_switch(struct checkout_opts *opts,
                           REF_NODEREF, DIE_ON_ERR);
                if (!opts->quiet) {
                        if (old->path)
-                               fprintf(stderr, "Note: moving to \"%s\" which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n  git checkout -b <new_branch_name>\n", new->name);
+                               fprintf(stderr, "Note: moving to '%s' which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n  git checkout -b <new_branch_name>\n", new->name);
                        describe_detached_head("HEAD is now at", new->commit);
                }
        }
@@ -545,26 +550,18 @@ static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
                parse_commit(new->commit);
        }
 
+       ret = merge_working_tree(opts, &old, new);
+       if (ret)
+               return ret;
+
        /*
-        * If we were on a detached HEAD, but we are now moving to
+        * If we were on a detached HEAD, but have now moved to
         * a new commit, we want to mention the old commit once more
         * to remind the user that it might be lost.
         */
        if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
                describe_detached_head("Previous HEAD position was", old.commit);
 
-       if (!old.commit && !opts->force) {
-               if (!opts->quiet) {
-                       fprintf(stderr, "warning: You appear to be on a branch yet to be born.\n");
-                       fprintf(stderr, "warning: Forcing checkout of %s.\n", new->name);
-               }
-               opts->force = 1;
-       }
-
-       ret = merge_working_tree(opts, &old, new);
-       if (ret)
-               return ret;
-
        update_refs_for_switch(opts, &old, new);
 
        ret = post_checkout_hook(old.commit, new->commit, 1);
@@ -576,6 +573,47 @@ static int git_checkout_config(const char *var, const char *value, void *cb)
        return git_xmerge_config(var, value, cb);
 }
 
+static int interactive_checkout(const char *revision, const char **pathspec,
+                               struct checkout_opts *opts)
+{
+       return run_add_interactive(revision, "--patch=checkout", pathspec);
+}
+
+struct tracking_name_data {
+       const char *name;
+       char *remote;
+       int unique;
+};
+
+static int check_tracking_name(const char *refname, const unsigned char *sha1,
+                              int flags, void *cb_data)
+{
+       struct tracking_name_data *cb = cb_data;
+       const char *slash;
+
+       if (prefixcmp(refname, "refs/remotes/"))
+               return 0;
+       slash = strchr(refname + 13, '/');
+       if (!slash || strcmp(slash + 1, cb->name))
+               return 0;
+       if (cb->remote) {
+               cb->unique = 0;
+               return 0;
+       }
+       cb->remote = xstrdup(refname);
+       return 0;
+}
+
+static const char *unique_tracking_name(const char *name)
+{
+       struct tracking_name_data cb_data = { name, NULL, 1 };
+       for_each_ref(check_tracking_name, &cb_data);
+       if (cb_data.unique)
+               return cb_data.remote;
+       free(cb_data.remote);
+       return NULL;
+}
+
 int cmd_checkout(int argc, const char **argv, const char *prefix)
 {
        struct checkout_opts opts;
@@ -584,6 +622,8 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
        struct branch_info new;
        struct tree *source_tree = NULL;
        char *conflict_style = NULL;
+       int patch_mode = 0;
+       int dwim_new_local_branch = 1;
        struct option options[] = {
                OPT__QUIET(&opts.quiet),
                OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
@@ -594,10 +634,14 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                            2),
                OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
                            3),
-               OPT_BOOLEAN('f', NULL, &opts.force, "force"),
+               OPT_BOOLEAN('f', "force", &opts.force, "force"),
                OPT_BOOLEAN('m', "merge", &opts.merge, "merge"),
                OPT_STRING(0, "conflict", &conflict_style, "style",
                           "conflict style (merge or diff3)"),
+               OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
+               { OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
+                 "second guess 'git checkout no-such-branch'",
+                 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
                OPT_END(),
        };
        int has_dash_dash;
@@ -609,9 +653,13 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
 
        opts.track = BRANCH_TRACK_UNSPECIFIED;
 
-       argc = parse_options(argc, argv, options, checkout_usage,
+       argc = parse_options(argc, argv, prefix, options, checkout_usage,
                             PARSE_OPT_KEEP_DASHDASH);
 
+       if (patch_mode && (opts.track > 0 || opts.new_branch
+                          || opts.new_branch_log || opts.merge || opts.force))
+               die ("--patch is incompatible with all other options");
+
        /* --track without -b should DWIM */
        if (0 < opts.track && !opts.new_branch) {
                const char *argv0 = argv[0];
@@ -627,8 +675,6 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                opts.new_branch = argv0 + 1;
        }
 
-       if (opts.track == BRANCH_TRACK_UNSPECIFIED)
-               opts.track = git_branch_track;
        if (conflict_style) {
                opts.merge = 1; /* implied */
                git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
@@ -652,6 +698,11 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
         *   With no paths, if <something> is a commit, that is to
         *   switch to the branch or detach HEAD at it.
         *
+        *   With no paths, if <something> is _not_ a commit, no -t nor -b
+        *   was given, and there is a tracking branch whose name is
+        *   <something> in one and only one remote, then this is a short-hand
+        *   to fork local <something> from that remote tracking branch.
+        *
         *   Otherwise <something> shall not be ambiguous.
         *   - If it's *only* a reference, treat it like case (1).
         *   - If it's only a path, treat it like case (2).
@@ -668,18 +719,35 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
                arg = argv[0];
                has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
 
+               if (!strcmp(arg, "-"))
+                       arg = "@{-1}";
+
                if (get_sha1(arg, rev)) {
                        if (has_dash_dash)          /* case (1) */
                                die("invalid reference: %s", arg);
-                       goto no_reference;          /* case (3 -> 2) */
+                       if (!patch_mode &&
+                           dwim_new_local_branch &&
+                           opts.track == BRANCH_TRACK_UNSPECIFIED &&
+                           !opts.new_branch &&
+                           !check_filename(NULL, arg) &&
+                           argc == 1) {
+                               const char *remote = unique_tracking_name(arg);
+                               if (!remote || get_sha1(remote, rev))
+                                       goto no_reference;
+                               opts.new_branch = arg;
+                               arg = remote;
+                               /* DWIMmed to create local branch */
+                       }
+                       else
+                               goto no_reference;
                }
 
                /* we can't end up being in (2) anymore, eat the argument */
                argv++;
                argc--;
 
+               new.name = arg;
                if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
-                       new.name = arg;
                        setup_branch_path(&new);
                        if (resolve_ref(new.path, rev, 1, NULL))
                                new.commit = lookup_commit_reference(rev);
@@ -709,12 +777,19 @@ int cmd_checkout(int argc, const char **argv, const char *prefix)
        }
 
 no_reference:
+
+       if (opts.track == BRANCH_TRACK_UNSPECIFIED)
+               opts.track = git_branch_track;
+
        if (argc) {
                const char **pathspec = get_pathspec(prefix, argv);
 
                if (!pathspec)
                        die("invalid path specification");
 
+               if (patch_mode)
+                       return interactive_checkout(new.name, pathspec, &opts);
+
                /* Checkout paths */
                if (opts.new_branch) {
                        if (argc == 1) {
@@ -730,14 +805,16 @@ no_reference:
                return checkout_paths(source_tree, pathspec, &opts);
        }
 
+       if (patch_mode)
+               return interactive_checkout(new.name, NULL, &opts);
+
        if (opts.new_branch) {
                struct strbuf buf = STRBUF_INIT;
-               strbuf_addstr(&buf, "refs/heads/");
-               strbuf_addstr(&buf, opts.new_branch);
+               if (strbuf_check_branch_ref(&buf, opts.new_branch))
+                       die("git checkout: we do not like '%s' as a branch name.",
+                           opts.new_branch);
                if (!get_sha1(buf.buf, rev))
                        die("git checkout: branch %s already exists", opts.new_branch);
-               if (check_ref_format(buf.buf))
-                       die("git checkout: we do not like '%s' as a branch name.", opts.new_branch);
                strbuf_release(&buf);
        }