Merge branch 'il/branch-set-upstream'

* il/branch-set-upstream:
branch: warn and refuse to set a branch as a tracking branch of itself.
Add branch --set-upstream

diff --combined Documentation/git-branch.txt
index 44144d5a0dcede0203c4d053bc6c7349f82eb39c,a0d6a7a649f07942fe74a8895f654fdcdb2851e4..6b6c3da2d95ad2d5d94949034d5dd723f48d977a
--- 1/Documentation/git-branch.txt
--- 2/Documentation/git-branch.txt
+++ b/Documentation/git-branch.txt
@@@ -11,7 -11,7 +11,7 @@@ SYNOPSI
  'git branch' [--color | --no-color] [-r | -a]
        [-v [--abbrev=<length> | --no-abbrev]]
        [(--merged | --no-merged | --contains) [<commit>]]
- 'git branch' [--track | --no-track] [-l] [-f] <branchname> [<start-point>]
+ 'git branch' [--set-upstream | --track | --no-track] [-l] [-f] <branchname> [<start-point>]
  'git branch' (-m | -M) [<oldbranch>] <newbranch>
  'git branch' (-d | -D) [-r] <branchname>...
  
@@@ -38,7 -38,7 +38,7 @@@ working tree to it; use "git checkout <
  new branch.
  
  When a local branch is started off a remote branch, git sets up the
 -branch so that 'git-pull' will appropriately merge from
 +branch so that 'git pull' will appropriately merge from
  the remote branch. This behavior may be changed via the global
  `branch.autosetupmerge` configuration flag. That setting can be
  overridden by using the `--track` and `--no-track` options.
@@@ -55,7 -55,7 +55,7 @@@ has a reflog then the reflog will also 
  
  Use -r together with -d to delete remote-tracking branches. Note, that it
  only makes sense to delete remote-tracking branches if they no longer exist
 -in the remote repository or if 'git-fetch' was configured not to fetch
 +in the remote repository or if 'git fetch' was configured not to fetch
  them again. See also the 'prune' subcommand of linkgit:git-remote[1] for a
  way to clean up all obsolete remote-tracking branches.
  
@@@ -76,7 -76,7 +76,7 @@@ OPTION
  -f::
  --force::
        Reset <branchname> to <startpoint> if <branchname> exists
 -      already. Without `-f` 'git-branch' refuses to change an existing branch.
 +      already. Without `-f` 'git branch' refuses to change an existing branch.
  
  -m::
        Move/rename a branch and the corresponding reflog.
@@@ -129,6 -129,12 +129,12 @@@ start-point is either a local or remot
        Do not set up "upstream" configuration, even if the
        branch.autosetupmerge configuration variable is true.
  
+ --set-upstream::
+       If specified branch does not exist yet or if '--force' has been
+       given, acts exactly like '--track'. Otherwise sets up configuration
+       like '--track' would when creating the branch, except that where
+       branch points to is not changed.
+ 
  --contains <commit>::
        Only list branches which contain the specified commit.
  

diff --combined cache.h
index 4b15042c08afb2ba34ca6d08ebc5ca9b196ab7c8,e9ec537fed172546fdd2d906d15e9a6b840d785f..7d5c21e3f1e737504a7f4f8c76781b1552cb77e3
--- 1/cache.h
--- 2/cache.h
+++ b/cache.h
@@@ -288,7 -288,6 +288,7 @@@ static inline int ce_to_dtype(const str
  struct index_state {
        struct cache_entry **cache;
        unsigned int cache_nr, cache_alloc, cache_changed;
 +      struct string_list *resolve_undo;
        struct cache_tree *cache_tree;
        struct cache_time timestamp;
        void *alloc;
@@@ -343,9 -342,6 +343,9 @@@ static inline void remove_name_hash(str
  #define ce_modified(ce, st, options) ie_modified(&the_index, (ce), (st), (options))
  #define cache_name_exists(name, namelen, igncase) index_name_exists(&the_index, (name), (namelen), (igncase))
  #define cache_name_is_other(name, namelen) index_name_is_other(&the_index, (name), (namelen))
 +#define resolve_undo_clear() resolve_undo_clear_index(&the_index)
 +#define unmerge_cache_entry_at(at) unmerge_index_entry_at(&the_index, at)
 +#define unmerge_cache(pathspec) unmerge_index(&the_index, pathspec)
  #endif
  
  enum object_type {
@@@ -455,6 -451,7 +455,6 @@@ extern int index_name_pos(const struct 
  #define ADD_CACHE_JUST_APPEND 8               /* Append only; tree.c::read_tree() */
  #define ADD_CACHE_NEW_ONLY 16         /* Do not replace existing ones */
  extern int add_index_entry(struct index_state *, struct cache_entry *ce, int option);
 -extern struct cache_entry *refresh_cache_entry(struct cache_entry *ce, int really);
  extern void rename_index_entry_at(struct index_state *, int pos, const char *new_name);
  extern int remove_index_entry_at(struct index_state *, int pos);
  extern void remove_marked_cache_entries(struct index_state *istate);
@@@ -484,6 -481,9 +484,6 @@@ extern int index_fd(unsigned char *sha1
  extern int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object);
  extern void fill_stat_cache_info(struct cache_entry *ce, struct stat *st);
  
 -/* "careful lstat()" */
 -extern int check_path(const char *path, int len, struct stat *st, int skiplen);
 -
  #define REFRESH_REALLY                0x0001  /* ignore_valid */
  #define REFRESH_UNMERGED      0x0002  /* allow unmerged */
  #define REFRESH_QUIET         0x0004  /* be quiet about it */
@@@ -553,6 -553,7 +553,7 @@@ enum branch_track 
        BRANCH_TRACK_REMOTE,
        BRANCH_TRACK_ALWAYS,
        BRANCH_TRACK_EXPLICIT,
+       BRANCH_TRACK_OVERRIDE,
  };
  
  enum rebase_setup_type {
@@@ -627,6 -628,7 +628,6 @@@ static inline void hashclr(unsigned cha
  {
        memset(hash, 0, 20);
  }
 -extern int is_empty_blob_sha1(const unsigned char *sha1);
  
  #define EMPTY_TREE_SHA1_HEX \
        "4b825dc642cb6eb9a060e54bf8d69288fbee4904"
@@@ -696,6 -698,7 +697,6 @@@ extern int has_sha1_pack(const unsigne
  extern int has_sha1_file(const unsigned char *sha1);
  extern int has_loose_object_nonlocal(const unsigned char *sha1);
  
 -extern int has_pack_file(const unsigned char *sha1);
  extern int has_pack_index(const unsigned char *sha1);
  
  extern const signed char hexval_table[256];
@@@ -796,6 -799,8 +797,6 @@@ extern int has_symlink_leading_path(con
  extern int threaded_has_symlink_leading_path(struct cache_def *, const char *, int);
  extern int has_symlink_or_noent_leading_path(const char *name, int len);
  extern int has_dirs_only_path(const char *name, int len, int prefix_len);
 -extern void invalidate_lstat_cache(const char *name, int len);
 -extern void clear_lstat_cache(void);
  extern void schedule_dir_for_removal(const char *name, int len);
  extern void remove_scheduled_dirs(void);
  
@@@ -935,11 -940,7 +936,11 @@@ extern const char *config_exclusive_fil
  #define MAX_GITNAME (1000)
  extern char git_default_email[MAX_GITNAME];
  extern char git_default_name[MAX_GITNAME];
 +#define IDENT_NAME_GIVEN 01
 +#define IDENT_MAIL_GIVEN 02
 +#define IDENT_ALL_GIVEN (IDENT_NAME_GIVEN|IDENT_MAIL_GIVEN)
  extern int user_ident_explicitly_given;
 +extern int user_ident_sufficiently_given(void);
  
  extern const char *git_commit_encoding;
  extern const char *git_log_output_encoding;
@@@ -1007,7 -1008,6 +1008,7 @@@ extern int diff_auto_refresh_index
  
  /* match-trees.c */
  void shift_tree(const unsigned char *, const unsigned char *, unsigned char *, int);
 +void shift_tree_by(const unsigned char *, const unsigned char *, unsigned char *, const char *);
  
  /*
   * whitespace rules.