diff --git a/Documentation/git-merge.txt b/Documentation/git-merge.txt index 1f94908e3c..273a1009be 100644 --- a/Documentation/git-merge.txt +++ b/Documentation/git-merge.txt @@ -104,6 +104,10 @@ commit or stash your changes before running 'git merge'. If no commit is given from the command line, merge the remote-tracking branches that the current branch is configured to use as its upstream. See also the configuration section of this manual page. ++ +When `FETCH_HEAD` (and no other commit) is specified, the branches +recorded in the `.git/FETCH_HEAD` file by the previous invocation +of `git fetch` for merging are merged to the current branch. PRE-MERGE CHECKS diff --git a/builtin/merge.c b/builtin/merge.c index 3b0f8f96d4..f89f60e11a 100644 --- a/builtin/merge.c +++ b/builtin/merge.c @@ -492,8 +492,7 @@ static void merge_name(const char *remote, struct strbuf *msg) } if (len) { struct strbuf truname = STRBUF_INIT; - strbuf_addstr(&truname, "refs/heads/"); - strbuf_addstr(&truname, remote); + strbuf_addf(&truname, "refs/heads/%s", remote); strbuf_setlen(&truname, truname.len - len); if (ref_exists(truname.buf)) { strbuf_addf(msg, @@ -504,28 +503,7 @@ static void merge_name(const char *remote, struct strbuf *msg) strbuf_release(&truname); goto cleanup; } - } - - if (!strcmp(remote, "FETCH_HEAD") && - !access(git_path("FETCH_HEAD"), R_OK)) { - const char *filename; - FILE *fp; - struct strbuf line = STRBUF_INIT; - char *ptr; - - filename = git_path("FETCH_HEAD"); - fp = fopen(filename, "r"); - if (!fp) - die_errno(_("could not open '%s' for reading"), - filename); - strbuf_getline(&line, fp, '\n'); - fclose(fp); - ptr = strstr(line.buf, "\tnot-for-merge\t"); - if (ptr) - strbuf_remove(&line, ptr-line.buf+1, 13); - strbuf_addbuf(msg, &line); - strbuf_release(&line); - goto cleanup; + strbuf_release(&truname); } if (remote_head->util) { @@ -1037,28 +1015,24 @@ static int default_edit_option(void) st_stdin.st_mode == st_stdout.st_mode); } -static struct commit_list *collect_parents(struct commit *head_commit, - int *head_subsumed, - int argc, const char **argv) +static struct commit_list *reduce_parents(struct commit *head_commit, + int *head_subsumed, + struct commit_list *remoteheads) { - int i; - struct commit_list *remoteheads = NULL, *parents, *next; - struct commit_list **remotes = &remoteheads; + struct commit_list *parents, *next, **remotes = &remoteheads; - if (head_commit) - remotes = &commit_list_insert(head_commit, remotes)->next; - for (i = 0; i < argc; i++) { - struct commit *commit = get_merge_parent(argv[i]); - if (!commit) - help_unknown_ref(argv[i], "merge", - "not something we can merge"); - remotes = &commit_list_insert(commit, remotes)->next; - } - *remotes = NULL; + /* + * Is the current HEAD reachable from another commit being + * merged? If so we do not want to record it as a parent of + * the resulting merge, unless --no-ff is given. We will flip + * this variable to 0 when we find HEAD among the independent + * tips being merged. + */ + *head_subsumed = 1; + /* Find what parents to record by checking independent ones. */ parents = reduce_heads(remoteheads); - *head_subsumed = 1; /* we will flip this to 0 when we find it */ for (remoteheads = NULL, remotes = &remoteheads; parents; parents = next) { @@ -1068,10 +1042,122 @@ static struct commit_list *collect_parents(struct commit *head_commit, *head_subsumed = 0; else remotes = &commit_list_insert(commit, remotes)->next; + free(parents); } return remoteheads; } +static void prepare_merge_message(struct strbuf *merge_names, struct strbuf *merge_msg) +{ + struct fmt_merge_msg_opts opts; + + memset(&opts, 0, sizeof(opts)); + opts.add_title = !have_message; + opts.shortlog_len = shortlog_len; + opts.credit_people = (0 < option_edit); + + fmt_merge_msg(merge_names, merge_msg, &opts); + if (merge_msg->len) + strbuf_setlen(merge_msg, merge_msg->len - 1); +} + +static void handle_fetch_head(struct commit_list **remotes, struct strbuf *merge_names) +{ + const char *filename; + int fd, pos, npos; + struct strbuf fetch_head_file = STRBUF_INIT; + + if (!merge_names) + merge_names = &fetch_head_file; + + filename = git_path("FETCH_HEAD"); + fd = open(filename, O_RDONLY); + if (fd < 0) + die_errno(_("could not open '%s' for reading"), filename); + + if (strbuf_read(merge_names, fd, 0) < 0) + die_errno(_("could not read '%s'"), filename); + if (close(fd) < 0) + die_errno(_("could not close '%s'"), filename); + + for (pos = 0; pos < merge_names->len; pos = npos) { + unsigned char sha1[20]; + char *ptr; + struct commit *commit; + + ptr = strchr(merge_names->buf + pos, '\n'); + if (ptr) + npos = ptr - merge_names->buf + 1; + else + npos = merge_names->len; + + if (npos - pos < 40 + 2 || + get_sha1_hex(merge_names->buf + pos, sha1)) + commit = NULL; /* bad */ + else if (memcmp(merge_names->buf + pos + 40, "\t\t", 2)) + continue; /* not-for-merge */ + else { + char saved = merge_names->buf[pos + 40]; + merge_names->buf[pos + 40] = '\0'; + commit = get_merge_parent(merge_names->buf + pos); + merge_names->buf[pos + 40] = saved; + } + if (!commit) { + if (ptr) + *ptr = '\0'; + die("not something we can merge in %s: %s", + filename, merge_names->buf + pos); + } + remotes = &commit_list_insert(commit, remotes)->next; + } + + if (merge_names == &fetch_head_file) + strbuf_release(&fetch_head_file); +} + +static struct commit_list *collect_parents(struct commit *head_commit, + int *head_subsumed, + int argc, const char **argv, + struct strbuf *merge_msg) +{ + int i; + struct commit_list *remoteheads = NULL; + struct commit_list **remotes = &remoteheads; + struct strbuf merge_names = STRBUF_INIT, *autogen = NULL; + + if (merge_msg && (!have_message || shortlog_len)) + autogen = &merge_names; + + if (head_commit) + remotes = &commit_list_insert(head_commit, remotes)->next; + + if (argc == 1 && !strcmp(argv[0], "FETCH_HEAD")) { + handle_fetch_head(remotes, autogen); + remoteheads = reduce_parents(head_commit, head_subsumed, remoteheads); + } else { + for (i = 0; i < argc; i++) { + struct commit *commit = get_merge_parent(argv[i]); + if (!commit) + help_unknown_ref(argv[i], "merge", + "not something we can merge"); + remotes = &commit_list_insert(commit, remotes)->next; + } + remoteheads = reduce_parents(head_commit, head_subsumed, remoteheads); + if (autogen) { + struct commit_list *p; + for (p = remoteheads; p; p = p->next) + merge_name(merge_remote_util(p->item)->name, autogen); + } + } + + if (autogen) { + prepare_merge_message(autogen, merge_msg); + strbuf_release(autogen); + } + + return remoteheads; +} + int cmd_merge(int argc, const char **argv, const char *prefix) { unsigned char result_tree[20]; @@ -1158,19 +1244,44 @@ int cmd_merge(int argc, const char **argv, const char *prefix) option_commit = 0; } - if (!abort_current_merge) { - if (!argc) { - if (default_to_upstream) - argc = setup_with_upstream(&argv); - else - die(_("No commit specified and merge.defaultToUpstream not set.")); - } else if (argc == 1 && !strcmp(argv[0], "-")) - argv[0] = "@{-1}"; + if (!argc) { + if (default_to_upstream) + argc = setup_with_upstream(&argv); + else + die(_("No commit specified and merge.defaultToUpstream not set.")); + } else if (argc == 1 && !strcmp(argv[0], "-")) { + argv[0] = "@{-1}"; } + if (!argc) usage_with_options(builtin_merge_usage, builtin_merge_options); + if (!head_commit) { + struct commit *remote_head; + /* + * If the merged head is a valid one there is no reason + * to forbid "git merge" into a branch yet to be born. + * We do the same for "git pull". + */ + if (squash) + die(_("Squash commit into empty head not supported yet")); + if (fast_forward == FF_NO) + die(_("Non-fast-forward commit does not make sense into " + "an empty head")); + remoteheads = collect_parents(head_commit, &head_subsumed, + argc, argv, NULL); + remote_head = remoteheads->item; + if (!remote_head) + die(_("%s - not something we can merge"), argv[0]); + if (remoteheads->next) + die(_("Can merge only exactly one commit into empty head")); + read_empty(remote_head->object.sha1, 0); + update_ref("initial pull", "HEAD", remote_head->object.sha1, + NULL, 0, UPDATE_REFS_DIE_ON_ERR); + goto done; + } + /* * This could be traditional "merge HEAD ..." and * the way we can tell it is to see if the second token is HEAD, @@ -1179,40 +1290,16 @@ int cmd_merge(int argc, const char **argv, const char *prefix) * Traditional format never would have "-m" so it is an * additional safety measure to check for it. */ - - if (!have_message && head_commit && + if (!have_message && is_old_style_invocation(argc, argv, head_commit->object.sha1)) { + warning("old-style 'git merge HEAD ' is deprecated."); strbuf_addstr(&merge_msg, argv[0]); head_arg = argv[1]; argv += 2; argc -= 2; - remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv); - } else if (!head_commit) { - struct commit *remote_head; - /* - * If the merged head is a valid one there is no reason - * to forbid "git merge" into a branch yet to be born. - * We do the same for "git pull". - */ - if (argc != 1) - die(_("Can merge only exactly one commit into " - "empty head")); - if (squash) - die(_("Squash commit into empty head not supported yet")); - if (fast_forward == FF_NO) - die(_("Non-fast-forward commit does not make sense into " - "an empty head")); - remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv); - remote_head = remoteheads->item; - if (!remote_head) - die(_("%s - not something we can merge"), argv[0]); - read_empty(remote_head->object.sha1, 0); - update_ref("initial pull", "HEAD", remote_head->object.sha1, - NULL, 0, UPDATE_REFS_DIE_ON_ERR); - goto done; + remoteheads = collect_parents(head_commit, &head_subsumed, + argc, argv, NULL); } else { - struct strbuf merge_names = STRBUF_INIT; - /* We are invoked directly as the first-class UI. */ head_arg = "HEAD"; @@ -1221,21 +1308,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix) * the standard merge summary message to be appended * to the given message. */ - remoteheads = collect_parents(head_commit, &head_subsumed, argc, argv); - for (p = remoteheads; p; p = p->next) - merge_name(merge_remote_util(p->item)->name, &merge_names); - - if (!have_message || shortlog_len) { - struct fmt_merge_msg_opts opts; - memset(&opts, 0, sizeof(opts)); - opts.add_title = !have_message; - opts.shortlog_len = shortlog_len; - opts.credit_people = (0 < option_edit); - - fmt_merge_msg(&merge_names, &merge_msg, &opts); - if (merge_msg.len) - strbuf_setlen(&merge_msg, merge_msg.len - 1); - } + remoteheads = collect_parents(head_commit, &head_subsumed, + argc, argv, &merge_msg); } if (!head_commit || !argc) diff --git a/git-cvsimport.perl b/git-cvsimport.perl index 73d367cea8..82ecb0343a 100755 --- a/git-cvsimport.perl +++ b/git-cvsimport.perl @@ -1162,7 +1162,7 @@ sub commit { die "Fast-forward update failed: $?\n" if $?; } else { - system(qw(git merge cvsimport HEAD), "$remote/$opt_o"); + system(qw(git merge -m cvsimport), "$remote/$opt_o"); die "Could not merge $opt_o into the current branch.\n" if $?; } } else { diff --git a/git-pull.sh b/git-pull.sh index ad442264cb..9ed01fd219 100755 --- a/git-pull.sh +++ b/git-pull.sh @@ -323,7 +323,6 @@ then fi fi -merge_name=$(git fmt-merge-msg $log_arg <"$GIT_DIR/FETCH_HEAD") || exit case "$rebase" in true) eval="git-rebase $diffstat $strategy_args $merge_args $rebase_args $verbosity" @@ -334,7 +333,7 @@ true) eval="git-merge $diffstat $no_commit $verify_signatures $edit $squash $no_ff $ff_only" eval="$eval $log_arg $strategy_args $merge_args $verbosity $progress" eval="$eval $gpg_sign_args" - eval="$eval \"\$merge_name\" HEAD $merge_head" + eval="$eval FETCH_HEAD" ;; esac eval "exec $eval" diff --git a/t/t3033-merge-toplevel.sh b/t/t3033-merge-toplevel.sh new file mode 100755 index 0000000000..46aadc410b --- /dev/null +++ b/t/t3033-merge-toplevel.sh @@ -0,0 +1,136 @@ +#!/bin/sh + +test_description='"git merge" top-level frontend' + +. ./test-lib.sh + +t3033_reset () { + git checkout -B master two && + git branch -f left three && + git branch -f right four +} + +test_expect_success setup ' + test_commit one && + git branch left && + git branch right && + test_commit two && + git checkout left && + test_commit three && + git checkout right && + test_commit four && + git checkout master +' + +# Local branches + +test_expect_success 'merge an octopus into void' ' + t3033_reset && + git checkout --orphan test && + git rm -fr . && + test_must_fail git merge left right && + test_must_fail git rev-parse --verify HEAD && + git diff --quiet && + test_must_fail git rev-parse HEAD +' + +test_expect_success 'merge an octopus, fast-forward (ff)' ' + t3033_reset && + git reset --hard one && + git merge left right && + # one is ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^3 && + git rev-parse HEAD^1 HEAD^2 | sort >actual && + git rev-parse three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge octopus, non-fast-forward (ff)' ' + t3033_reset && + git reset --hard one && + git merge --no-ff left right && + # one is ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse one three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge octopus, fast-forward (does not ff)' ' + t3033_reset && + git merge left right && + # two (master) is not an ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse two three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge octopus, non-fast-forward' ' + t3033_reset && + git merge --no-ff left right && + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse two three four | sort >expect && + test_cmp expect actual +' + +# The same set with FETCH_HEAD + +test_expect_success 'merge FETCH_HEAD octopus into void' ' + t3033_reset && + git checkout --orphan test && + git rm -fr . && + git fetch . left right && + test_must_fail git merge FETCH_HEAD && + test_must_fail git rev-parse --verify HEAD && + git diff --quiet && + test_must_fail git rev-parse HEAD +' + +test_expect_success 'merge FETCH_HEAD octopus fast-forward (ff)' ' + t3033_reset && + git reset --hard one && + git fetch . left right && + git merge FETCH_HEAD && + # one is ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^3 && + git rev-parse HEAD^1 HEAD^2 | sort >actual && + git rev-parse three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge FETCH_HEAD octopus non-fast-forward (ff)' ' + t3033_reset && + git reset --hard one && + git fetch . left right && + git merge --no-ff FETCH_HEAD && + # one is ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse one three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge FETCH_HEAD octopus fast-forward (does not ff)' ' + t3033_reset && + git fetch . left right && + git merge FETCH_HEAD && + # two (master) is not an ancestor of three (left) and four (right) + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse two three four | sort >expect && + test_cmp expect actual +' + +test_expect_success 'merge FETCH_HEAD octopus non-fast-forward' ' + t3033_reset && + git fetch . left right && + git merge --no-ff FETCH_HEAD && + test_must_fail git rev-parse --verify HEAD^4 && + git rev-parse HEAD^1 HEAD^2 HEAD^3 | sort >actual && + git rev-parse two three four | sort >expect && + test_cmp expect actual +' + +test_done diff --git a/t/t3402-rebase-merge.sh b/t/t3402-rebase-merge.sh index 5a27ec9b5e..8f64505e4f 100755 --- a/t/t3402-rebase-merge.sh +++ b/t/t3402-rebase-merge.sh @@ -47,7 +47,7 @@ test_expect_success setup ' ' test_expect_success 'reference merge' ' - git merge -s recursive "reference merge" HEAD master + git merge -s recursive -m "reference merge" master ' PRE_REBASE=$(git rev-parse test-rebase) diff --git a/t/t5520-pull.sh b/t/t5520-pull.sh index 227d293350..7efd45bc27 100755 --- a/t/t5520-pull.sh +++ b/t/t5520-pull.sh @@ -9,36 +9,27 @@ modify () { mv "$2.x" "$2" } -D=`pwd` - test_expect_success setup ' - echo file >file && git add file && git commit -a -m original - ' test_expect_success 'pulling into void' ' - mkdir cloned && - cd cloned && - git init && - git pull .. -' - -cd "$D" - -test_expect_success 'checking the results' ' + git init cloned && + ( + cd cloned && + git pull .. + ) && test -f file && test -f cloned/file && test_cmp file cloned/file ' test_expect_success 'pulling into void using master:master' ' - mkdir cloned-uho && + git init cloned-uho && ( cd cloned-uho && - git init && git pull .. master:master ) && test -f file && @@ -71,7 +62,6 @@ test_expect_success 'pulling into void does not overwrite staged files' ' ) ' - test_expect_success 'pulling into void does not remove new staged files' ' git init cloned-staged-new && ( @@ -86,6 +76,15 @@ test_expect_success 'pulling into void does not remove new staged files' ' ) ' +test_expect_success 'pulling into void must not create an octopus' ' + git init cloned-octopus && + ( + cd cloned-octopus && + test_must_fail git pull .. master master && + ! test -f file + ) +' + test_expect_success 'test . as a remote' ' git branch copy master && diff --git a/t/t6020-merge-df.sh b/t/t6020-merge-df.sh index 27c3d73961..2af1beec5f 100755 --- a/t/t6020-merge-df.sh +++ b/t/t6020-merge-df.sh @@ -24,7 +24,7 @@ test_expect_success 'prepare repository' ' ' test_expect_success 'Merge with d/f conflicts' ' - test_expect_code 1 git merge "merge msg" B master + test_expect_code 1 git merge -m "merge msg" master ' test_expect_success 'F/D conflict' ' diff --git a/t/t6021-merge-criss-cross.sh b/t/t6021-merge-criss-cross.sh index d15b313d4b..213deecab1 100755 --- a/t/t6021-merge-criss-cross.sh +++ b/t/t6021-merge-criss-cross.sh @@ -48,7 +48,7 @@ echo "1 " > file && git commit -m "C3" file && git branch C3 && -git merge "pre E3 merge" B A && +git merge -m "pre E3 merge" A && echo "1 2 3 changed in E3, branch B. New file size @@ -61,7 +61,7 @@ echo "1 " > file && git commit -m "E3" file && git checkout A && -git merge "pre D8 merge" A C3 && +git merge -m "pre D8 merge" C3 && echo "1 2 3 changed in C3, branch B @@ -73,7 +73,7 @@ echo "1 9" > file && git commit -m D8 file' -test_expect_success 'Criss-cross merge' 'git merge "final merge" A B' +test_expect_success 'Criss-cross merge' 'git merge -m "final merge" B' cat > file-expect <