Merge branch 'pn/commit-autosquash'

* pn/commit-autosquash:
  add tests of commit --squash
  commit: --squash option for use with rebase --autosquash
  add tests of commit --fixup
  commit: --fixup option for use with rebase --autosquash
  pretty.c: teach format_commit_message() to reencode the output
  commit: helper methods to reduce redundant blocks of code

Conflicts:
	Documentation/git-commit.txt
	t/t3415-rebase-autosquash.sh

3 files changed, 56 insertions, 30 deletions

diff --git a/builtin/commit.c b/builtin/commit.c
index 4fd1a1692f..6d867d4018 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -69,6 +69,7 @@ static enum {
 static const char *logfile, *force_author;
 static const char *template_file;
 static char *edit_message, *use_message;
+static char *fixup_message, *squash_message;
 static char *author_name, *author_email, *author_date;
 static int all, edit_flag, also, interactive, only, amend, signoff;
 static int quiet, verbose, no_verify, allow_empty, dry_run, renew_authorship;
@@ -124,6 +125,8 @@ static struct option builtin_commit_options[] = {
 	OPT_CALLBACK('m', "message", &message, "MESSAGE", "specify commit message", opt_parse_m),
 	OPT_STRING('c', "reedit-message", &edit_message, "COMMIT", "reuse and edit message from specified commit"),
 	OPT_STRING('C', "reuse-message", &use_message, "COMMIT", "reuse message from specified commit"),
+	OPT_STRING(0, "fixup", &fixup_message, "COMMIT", "use autosquash formatted message to fixup specified commit"),
+	OPT_STRING(0, "squash", &squash_message, "COMMIT", "use autosquash formatted message to squash specified commit"),
 	OPT_BOOLEAN(0, "reset-author", &renew_authorship, "the commit is authored by me now (used with -C-c/--amend)"),
 	OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
 	OPT_FILENAME('t', "template", &template_file, "use specified template file"),
@@ -565,6 +568,25 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	if (!no_verify && run_hook(index_file, "pre-commit", NULL))
 		return 0;
 
+	if (squash_message) {
+		/*
+		 * Insert the proper subject line before other commit
+		 * message options add their content.
+		 */
+		if (use_message && !strcmp(use_message, squash_message))
+			strbuf_addstr(&sb, "squash! ");
+		else {
+			struct pretty_print_context ctx = {0};
+			struct commit *c;
+			c = lookup_commit_reference_by_name(squash_message);
+			if (!c)
+				die("could not lookup commit %s", squash_message);
+			ctx.output_encoding = get_commit_output_encoding();
+			format_commit_message(c, "squash! %s\n\n", &sb,
+					      &ctx);
+		}
+	}
+
 	if (message.len) {
 		strbuf_addbuf(&sb, &message);
 		hook_arg1 = "message";
@@ -586,6 +608,16 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 		strbuf_add(&sb, buffer + 2, strlen(buffer + 2));
 		hook_arg1 = "commit";
 		hook_arg2 = use_message;
+	} else if (fixup_message) {
+		struct pretty_print_context ctx = {0};
+		struct commit *commit;
+		commit = lookup_commit_reference_by_name(fixup_message);
+		if (!commit)
+			die("could not lookup commit %s", fixup_message);
+		ctx.output_encoding = get_commit_output_encoding();
+		format_commit_message(commit, "fixup! %s\n\n",
+				      &sb, &ctx);
+		hook_arg1 = "message";
 	} else if (!stat(git_path("MERGE_MSG"), &statbuf)) {
 		if (strbuf_read_file(&sb, git_path("MERGE_MSG"), 0) < 0)
 			die_errno("could not read MERGE_MSG");
@@ -607,6 +639,16 @@ static int prepare_to_commit(const char *index_file, const char *prefix,
 	else if (in_merge)
 		hook_arg1 = "merge";
 
+	if (squash_message) {
+		/*
+		 * If squash_commit was used for the commit subject,
+		 * then we're possibly hijacking other commit log options.
+		 * Reset the hook args to tell the real story.
+		 */
+		hook_arg1 = "message";
+		hook_arg2 = "";
+	}
+
 	fp = fopen(git_path(commit_editmsg), "w");
 	if (fp == NULL)
 		die_errno("could not open '%s'", git_path(commit_editmsg));
@@ -863,7 +905,7 @@ static int parse_and_validate_options(int argc, const char *argv[],
 	if (force_author && renew_authorship)
 		die("Using both --reset-author and --author does not make sense");
 
-	if (logfile || message.len || use_message)
+	if (logfile || message.len || use_message || fixup_message)
 		use_editor = 0;
 	if (edit_flag)
 		use_editor = 1;
@@ -878,48 +920,35 @@ static int parse_and_validate_options(int argc, const char *argv[],
 		die("You have nothing to amend.");
 	if (amend && in_merge)
 		die("You are in the middle of a merge -- cannot amend.");
-
+	if (fixup_message && squash_message)
+		die("Options --squash and --fixup cannot be used together");
 	if (use_message)
 		f++;
 	if (edit_message)
 		f++;
+	if (fixup_message)
+		f++;
 	if (logfile)
 		f++;
 	if (f > 1)
-		die("Only one of -c/-C/-F can be used.");
+		die("Only one of -c/-C/-F/--fixup can be used.");
 	if (message.len && f > 0)
-		die("Option -m cannot be combined with -c/-C/-F.");
+		die("Option -m cannot be combined with -c/-C/-F/--fixup.");
 	if (edit_message)
 		use_message = edit_message;
-	if (amend && !use_message)
+	if (amend && !use_message && !fixup_message)
 		use_message = "HEAD";
 	if (!use_message && renew_authorship)
 		die("--reset-author can be used only with -C, -c or --amend.");
 	if (use_message) {
-		unsigned char sha1[20];
-		static char utf8[] = "UTF-8";
 		const char *out_enc;
-		char *enc, *end;
 		struct commit *commit;
 
-		if (get_sha1(use_message, sha1))
+		commit = lookup_commit_reference_by_name(use_message);
+		if (!commit)
 			die("could not lookup commit %s", use_message);
-		commit = lookup_commit_reference(sha1);
-		if (!commit || parse_commit(commit))
-			die("could not parse commit %s", use_message);
-
-		enc = strstr(commit->buffer, "\nencoding");
-		if (enc) {
-			end = strchr(enc + 10, '\n');
-			enc = xstrndup(enc + 10, end - (enc + 10));
-		} else {
-			enc = utf8;
-		}
-		out_enc = git_commit_encoding ? git_commit_encoding : utf8;
-
-		if (strcmp(out_enc, enc))
-			use_message_buffer =
-				reencode_string(commit->buffer, out_enc, enc);
+		out_enc = get_commit_output_encoding();
+		use_message_buffer = logmsg_reencode(commit, out_enc);
 
 		/*
 		 * If we failed to reencode the buffer, just copy it
@@ -929,8 +958,6 @@ static int parse_and_validate_options(int argc, const char *argv[],
 		 */
 		if (use_message_buffer == NULL)
 			use_message_buffer = xstrdup(commit->buffer);
-		if (enc != utf8)
-			free(enc);
 	}
 
 	if (!!also + !!only + !!all + !!interactive > 1)
diff --git a/builtin/log.c b/builtin/log.c
index d0297a1c5e..4191d9c4e5 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -329,8 +329,7 @@ static void show_tagger(char *buf, int len, struct rev_info *rev)
 	struct strbuf out = STRBUF_INIT;
 
 	pp_user_info("Tagger", rev->commit_format, &out, buf, rev->date_mode,
-		git_log_output_encoding ?
-		git_log_output_encoding: git_commit_encoding);
+		get_log_output_encoding());
 	printf("%s", out.buf);
 	strbuf_release(&out);
 }
diff --git a/builtin/mailinfo.c b/builtin/mailinfo.c
index 2320d981ce..71e6262a87 100644
--- a/builtin/mailinfo.c
+++ b/builtin/mailinfo.c
@@ -1032,7 +1032,7 @@ int cmd_mailinfo(int argc, const char **argv, const char *prefix)
 	 */
 	git_config(git_mailinfo_config, NULL);
 
-	def_charset = (git_commit_encoding ? git_commit_encoding : "UTF-8");
+	def_charset = get_commit_output_encoding();
 	metainfo_charset = def_charset;
 
 	while (1 < argc && argv[1][0] == '-') {