Fix tab completion in psql for ALTER DEFAULT PRIVILEGES

sfrost · sfrost · commit 2022d594da32 · 2016-12-23T21:01:48.000-05:00
When providing tab completion for ALTER DEFAULT PRIVILEGES, we are including the list of roles as possible options for completion after the GRANT or REVOKE. Further, we accept FOR ROLE/IN SCHEMA at the same time and in either order, but the tab completion was only working for one or the other. Lastly, we weren't using the actual list of allowed kinds of objects for default privileges for completion after the 'GRANT X ON' but instead were completeing to what 'GRANT X ON' supports, which isn't the ssame at all. Address these issues by improving the forward tab-completion for ALTER DEFAULT PRIVILEGES and then constrain and correct how the tail completion is done when it is for ALTER DEFAULT PRIVILEGES. Back-patch the forward/tail tab-completion to 9.6, where we made it easy to handle such cases. For 9.5 and earlier, correct the initial tab-completion to at least be correct as far as it goes and then add a check for GRANT/REVOKE to only tab-complete when the GRANT/REVOKE is the start of the command, so we don't try to do tab-completion after we get to the GRANT/REVOKE part of the ALTER DEFAULT PRIVILEGES command, which is better than providing incorrect completions. Initial patch for master and 9.6 by Gilles Darold, though I cleaned it up and added a few comments. All bugs in the 9.5 and earlier patch are mine. Discussion: https://www.postgresql.org/message-id/1614593c-e356-5b27-6dba-66320a9bc68b@dalibo.com
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
@@ -1187,7 +1187,7 @@ psql_completion(char *text, int start, int end)
 			 pg_strcasecmp(prev_wd, "PRIVILEGES") == 0)
 	{
 		static const char *const list_ALTER_DEFAULT_PRIVILEGES[] =
-		{"FOR ROLE", "FOR USER", "IN SCHEMA", NULL};
+		{"FOR ROLE", "IN SCHEMA", NULL};
 
 		COMPLETE_WITH_LIST(list_ALTER_DEFAULT_PRIVILEGES);
 	}
@@ -1197,19 +1197,26 @@ psql_completion(char *text, int start, int end)
 			 pg_strcasecmp(prev2_wd, "PRIVILEGES") == 0 &&
 			 pg_strcasecmp(prev_wd, "FOR") == 0)
 	{
-		static const char *const list_ALTER_DEFAULT_PRIVILEGES_FOR[] =
-		{"ROLE", "USER", NULL};
+		COMPLETE_WITH_CONST("ROLE");
+	}
+	/* ALTER DEFAULT PRIVILEGES FOR ROLE ... } */
+	else if (pg_strcasecmp(prev5_wd, "DEFAULT") == 0 &&
+			 pg_strcasecmp(prev4_wd, "PRIVILEGES") == 0 &&
+			 pg_strcasecmp(prev3_wd, "FOR") == 0)
+	{
+		static const char *const list_ALTER_DEFAULT_PRIVILEGES_REST[] =
+		{"GRANT", "REVOKE", "IN SCHEMA", NULL};
 
-		COMPLETE_WITH_LIST(list_ALTER_DEFAULT_PRIVILEGES_FOR);
+		COMPLETE_WITH_LIST(list_ALTER_DEFAULT_PRIVILEGES_REST);
 	}
-	/* ALTER DEFAULT PRIVILEGES { FOR ROLE ... | IN SCHEMA ... } */
+	/* ALTER DEFAULT PRIVILEGES IN SCHEMA ... } */
 	else if (pg_strcasecmp(prev5_wd, "DEFAULT") == 0 &&
 			 pg_strcasecmp(prev4_wd, "PRIVILEGES") == 0 &&
-			 (pg_strcasecmp(prev3_wd, "FOR") == 0 ||
-			  pg_strcasecmp(prev3_wd, "IN") == 0))
+			 pg_strcasecmp(prev3_wd, "IN") == 0 &&
+			 pg_strcasecmp(prev2_wd, "SCHEMA") == 0)
 	{
 		static const char *const list_ALTER_DEFAULT_PRIVILEGES_REST[] =
-		{"GRANT", "REVOKE", NULL};
+		{"GRANT", "REVOKE", "FOR ROLE", NULL};
 
 		COMPLETE_WITH_LIST(list_ALTER_DEFAULT_PRIVILEGES_REST);
 	}
@@ -2579,8 +2586,9 @@ psql_completion(char *text, int start, int end)
 
 /* GRANT && REVOKE */
 	/* Complete GRANT/REVOKE with a list of roles and privileges */
-	else if (pg_strcasecmp(prev_wd, "GRANT") == 0 ||
-			 pg_strcasecmp(prev_wd, "REVOKE") == 0)
+	else if (prev2_wd[0] == '\0' &&
+			 (pg_strcasecmp(prev_wd, "GRANT") == 0 ||
+			  pg_strcasecmp(prev_wd, "REVOKE") == 0))
 	{
 		COMPLETE_WITH_QUERY(Query_for_list_of_roles
 							" UNION SELECT 'SELECT'"
