From: Junio C Hamano <gitster@pobox.com>
Date: Tue, 16 Oct 2018 07:15:59 +0000 (+0900)
Subject: Merge branch 'ts/alias-of-alias'
X-Git-Tag: v2.20.0-rc0~192
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/506ee60d222f94a1598769feaba3b3621bd9fa1a?hp=-c

Merge branch 'ts/alias-of-alias'

An alias that expands to another alias has so far been forbidden,
but now it is allowed to create such an alias.

* ts/alias-of-alias:
t0014: introduce an alias testing suite
alias: show the call history when an alias is looping
alias: add support for aliases of an alias
---

506ee60d222f94a1598769feaba3b3621bd9fa1a
diff --combined git.c
index a6f4b44af5,a20eb4fa15..5920f8019b
--- a/git.c
+++ b/git.c
@@@ -508,7 -508,6 +508,7 @@@ static struct cmd_struct commands[] = 
  	{ "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
  	{ "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
  	{ "mktree", cmd_mktree, RUN_SETUP },
 +	{ "multi-pack-index", cmd_multi_pack_index, RUN_SETUP_GENTLY },
  	{ "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
  	{ "name-rev", cmd_name_rev, RUN_SETUP },
  	{ "notes", cmd_notes, RUN_SETUP },
@@@ -675,6 -674,8 +675,8 @@@ static void execv_dashed_external(cons
  static int run_argv(int *argcp, const char ***argv)
  {
  	int done_alias = 0;
+ 	struct string_list cmd_list = STRING_LIST_INIT_NODUP;
+ 	struct string_list_item *seen;
  
  	while (1) {
  		/*
@@@ -692,17 -693,37 +694,37 @@@
  		/* .. then try the external ones */
  		execv_dashed_external(*argv);
  
- 		/* It could be an alias -- this works around the insanity
+ 		seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
+ 		if (seen) {
+ 			int i;
+ 			struct strbuf sb = STRBUF_INIT;
+ 			for (i = 0; i < cmd_list.nr; i++) {
+ 				struct string_list_item *item = &cmd_list.items[i];
+ 
+ 				strbuf_addf(&sb, "\n  %s", item->string);
+ 				if (item == seen)
+ 					strbuf_addstr(&sb, " <==");
+ 				else if (i == cmd_list.nr - 1)
+ 					strbuf_addstr(&sb, " ==>");
+ 			}
+ 			die(_("alias loop detected: expansion of '%s' does"
+ 			      " not terminate:%s"), cmd_list.items[0].string, sb.buf);
+ 		}
+ 
+ 		string_list_append(&cmd_list, *argv[0]);
+ 
+ 		/*
+ 		 * It could be an alias -- this works around the insanity
  		 * of overriding "git log" with "git show" by having
  		 * alias.log = show
  		 */
- 		if (done_alias)
- 			break;
  		if (!handle_alias(argcp, argv))
  			break;
  		done_alias = 1;
  	}
  
+ 	string_list_clear(&cmd_list, 0);
+ 
  	return done_alias;
  }