Improve psql tab completion for COMMENT

Completion is added for more object types, like domain constraints, text
search-ish objects or policies.  Moreover, the area is reorganized,
changing the list of objects supported by COMMENT to be in the same
order as the documentation to ease future additions.

Author: Ken Kato
Reviewed-by: Fujii Masao, Shinya Kato, Suraj Khamkar, Michael Paquier
Discussion: https://postgr.es/m/6e0c2f3f657b229bea32d098d118f307@oss.nttdata.com

Author: michaelpq

src/bin/psql/tab-complete.c

@@ -2411,38 +2411,87 @@ psql_completion(const char *text, int start, int end)
 	else if (Matches("COMMENT"))
 		COMPLETE_WITH("ON");
 	else if (Matches("COMMENT", "ON"))
-		COMPLETE_WITH("ACCESS METHOD", "CAST", "COLLATION", "CONVERSION",
-					  "DATABASE", "EVENT TRIGGER", "EXTENSION",
-					  "FOREIGN DATA WRAPPER", "FOREIGN TABLE", "SERVER",
-					  "INDEX", "LANGUAGE", "POLICY", "PUBLICATION", "RULE",
-					  "SCHEMA", "SEQUENCE", "STATISTICS", "SUBSCRIPTION",
-					  "TABLE", "TYPE", "VIEW", "MATERIALIZED VIEW",
-					  "COLUMN", "AGGREGATE", "FUNCTION",
-					  "PROCEDURE", "ROUTINE",
-					  "OPERATOR", "TRIGGER", "CONSTRAINT", "DOMAIN",
-					  "LARGE OBJECT", "TABLESPACE", "TEXT SEARCH", "ROLE");
+		COMPLETE_WITH("ACCESS METHOD", "AGGREGATE", "CAST", "COLLATION",
+					  "COLUMN", "CONSTRAINT", "CONVERSION", "DATABASE",
+					  "DOMAIN", "EXTENSION", "EVENT TRIGGER",
+					  "FOREIGN DATA WRAPPER", "FOREIGN TABLE",
+					  "FUNCTION", "INDEX", "LANGUAGE", "LARGE OBJECT",
+					  "MATERIALIZED VIEW", "OPERATOR", "POLICY",
+					  "PROCEDURE", "PROCEDURAL LANGUAGE", "PUBLICATION", "ROLE",
+					  "ROUTINE", "RULE", "SCHEMA", "SEQUENCE", "SERVER",
+					  "STATISTICS", "SUBSCRIPTION", "TABLE",
+					  "TABLESPACE", "TEXT SEARCH", "TRANSFORM FOR",
+					  "TRIGGER", "TYPE", "VIEW");
 	else if (Matches("COMMENT", "ON", "ACCESS", "METHOD"))
 		COMPLETE_WITH_QUERY(Query_for_list_of_access_methods);
-	else if (Matches("COMMENT", "ON", "FOREIGN"))
-		COMPLETE_WITH("DATA WRAPPER", "TABLE");
-	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH"))
-		COMPLETE_WITH("CONFIGURATION", "DICTIONARY", "PARSER", "TEMPLATE");
 	else if (Matches("COMMENT", "ON", "CONSTRAINT"))
 		COMPLETE_WITH_QUERY(Query_for_all_table_constraints);
 	else if (Matches("COMMENT", "ON", "CONSTRAINT", MatchAny))
 		COMPLETE_WITH("ON");
 	else if (Matches("COMMENT", "ON", "CONSTRAINT", MatchAny, "ON"))
 	{
 		completion_info_charp = prev2_wd;
-		COMPLETE_WITH_QUERY(Query_for_list_of_tables_for_constraint);
+		COMPLETE_WITH_QUERY(Query_for_list_of_tables_for_constraint
+							" UNION SELECT 'DOMAIN'");
 	}
-	else if (Matches("COMMENT", "ON", "MATERIALIZED", "VIEW"))
-		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_matviews, NULL);
+	else if (Matches("COMMENT", "ON", "CONSTRAINT", MatchAny, "ON", "DOMAIN"))
+		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_domains, NULL);
 	else if (Matches("COMMENT", "ON", "EVENT", "TRIGGER"))
 		COMPLETE_WITH_QUERY(Query_for_list_of_event_triggers);
+	else if (Matches("COMMENT", "ON", "FOREIGN"))
+		COMPLETE_WITH("DATA WRAPPER", "TABLE");
+	else if (Matches("COMMENT", "ON", "FOREIGN", "TABLE"))
+		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_foreign_tables, NULL);
+	else if (Matches("COMMENT", "ON", "MATERIALIZED", "VIEW"))
+		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_matviews, NULL);
+	else if (Matches("COMMENT", "ON", "POLICY"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_policies);
+	else if (Matches("COMMENT", "ON", "POLICY", MatchAny))
+		COMPLETE_WITH("ON");
+	else if (Matches("COMMENT", "ON", "POLICY", MatchAny, "ON"))
+	{
+		completion_info_charp = prev2_wd;
+		COMPLETE_WITH_QUERY(Query_for_list_of_tables_for_policy);
+	}
+	else if (Matches("COMMENT", "ON", "PROCEDURAL", "LANGUAGE"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_languages);
+	else if (Matches("COMMENT", "ON", "RULE", MatchAny))
+		COMPLETE_WITH("ON");
+	else if (Matches("COMMENT", "ON", "RULE", MatchAny, "ON"))
+	{
+		completion_info_charp = prev2_wd;
+		COMPLETE_WITH_QUERY(Query_for_list_of_tables_for_rule);
+	}
+	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH"))
+		COMPLETE_WITH("CONFIGURATION", "DICTIONARY", "PARSER", "TEMPLATE");
+	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH", "CONFIGURATION"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_ts_configurations);
+	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH", "DICTIONARY"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_ts_dictionaries);
+	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH", "PARSER"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_ts_parsers);
+	else if (Matches("COMMENT", "ON", "TEXT", "SEARCH", "TEMPLATE"))
+		COMPLETE_WITH_QUERY(Query_for_list_of_ts_templates);
+	else if (Matches("COMMENT", "ON", "TRANSFORM", "FOR"))
+		COMPLETE_WITH_SCHEMA_QUERY(Query_for_list_of_datatypes, NULL);
+	else if (Matches("COMMENT", "ON", "TRANSFORM", "FOR", MatchAny))
+		COMPLETE_WITH("LANGUAGE");
+	else if (Matches("COMMENT", "ON", "TRANSFORM", "FOR", MatchAny, "LANGUAGE"))
+	{
+		completion_info_charp = prev2_wd;
+		COMPLETE_WITH_QUERY(Query_for_list_of_languages);
+	}
+	else if (Matches("COMMENT", "ON", "TRIGGER", MatchAny))
+		COMPLETE_WITH("ON");
+	else if (Matches("COMMENT", "ON", "TRIGGER", MatchAny, "ON"))
+	{
+		completion_info_charp = prev2_wd;
+		COMPLETE_WITH_QUERY(Query_for_list_of_tables_for_trigger);
+	}
 	else if (Matches("COMMENT", "ON", MatchAny, MatchAnyExcept("IS")) ||
 			 Matches("COMMENT", "ON", MatchAny, MatchAny, MatchAnyExcept("IS")) ||
-			 Matches("COMMENT", "ON", MatchAny, MatchAny, MatchAny, MatchAnyExcept("IS")))
+			 Matches("COMMENT", "ON", MatchAny, MatchAny, MatchAny, MatchAnyExcept("IS")) ||
+			 Matches("COMMENT", "ON", MatchAny, MatchAny, MatchAny, MatchAny, MatchAnyExcept("IS")))
 		COMPLETE_WITH("IS");
 
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