Add procedure support to pg_get_functiondef

This also makes procedures work in psql's \ef and \sf commands.
Reported-by: Pavel Stehule <pavel.stehule@gmail.com>

doc/src/sgml/func.sgml

@@ -17008,22 +17008,22 @@ SELECT pg_type_is_visible('myschema.widget'::regtype);
       <row>
        <entry><literal><function>pg_get_functiondef(<parameter>func_oid</parameter>)</function></literal></entry>
        <entry><type>text</type></entry>
-       <entry>get definition of a function</entry>
+       <entry>get definition of a function or procedure</entry>
       </row>
       <row>
        <entry><literal><function>pg_get_function_arguments(<parameter>func_oid</parameter>)</function></literal></entry>
        <entry><type>text</type></entry>
-       <entry>get argument list of function's definition (with default values)</entry>
+       <entry>get argument list of function's or procedure's definition (with default values)</entry>
       </row>
       <row>
        <entry><literal><function>pg_get_function_identity_arguments(<parameter>func_oid</parameter>)</function></literal></entry>
        <entry><type>text</type></entry>
-       <entry>get argument list to identify a function (without default values)</entry>
+       <entry>get argument list to identify a function or procedure (without default values)</entry>
       </row>
       <row>
        <entry><literal><function>pg_get_function_result(<parameter>func_oid</parameter>)</function></literal></entry>
        <entry><type>text</type></entry>
-       <entry>get <literal>RETURNS</literal> clause for function</entry>
+       <entry>get <literal>RETURNS</literal> clause for function (returns null for a procedure)</entry>
       </row>
       <row>
        <entry><literal><function>pg_get_indexdef(<parameter>index_oid</parameter>)</function></literal></entry>

doc/src/sgml/ref/psql-ref.sgml

@@ -1815,8 +1815,9 @@ Tue Oct 26 21:40:57 CEST 1999
 
         <listitem>
         <para>
-         This command fetches and edits the definition of the named function,
-         in the form of a <command>CREATE OR REPLACE FUNCTION</command> command.
+         This command fetches and edits the definition of the named function or procedure,
+         in the form of a <command>CREATE OR REPLACE FUNCTION</command> or
+         <command>CREATE OR REPLACE PROCEDURE</command> command.
          Editing is done in the same way as for <literal>\edit</literal>.
          After the editor exits, the updated command waits in the query buffer;
          type semicolon or <literal>\g</literal> to send it, or <literal>\r</literal>
@@ -2970,8 +2971,9 @@ testdb=&gt; <userinput>\setenv LESS -imx4F</userinput>
 
         <listitem>
         <para>
-         This command fetches and shows the definition of the named function,
-         in the form of a <command>CREATE OR REPLACE FUNCTION</command> command.
+         This command fetches and shows the definition of the named function or procedure,
+         in the form of a <command>CREATE OR REPLACE FUNCTION</command> or
+         <command>CREATE OR REPLACE PROCEDURE</command> command.
          The definition is printed to the current query output channel,
          as set by <command>\o</command>.
         </para>

src/backend/utils/adt/ruleutils.c

@@ -2449,6 +2449,7 @@ pg_get_functiondef(PG_FUNCTION_ARGS)
 	StringInfoData dq;
 	HeapTuple	proctup;
 	Form_pg_proc proc;
+	bool		isfunction;
 	Datum		tmp;
 	bool		isnull;
 	const char *prosrc;
@@ -2472,20 +2473,28 @@ pg_get_functiondef(PG_FUNCTION_ARGS)
 				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
 				 errmsg("\"%s\" is an aggregate function", name)));
 
+	isfunction = (proc->prorettype != InvalidOid);
+
 	/*
 	 * We always qualify the function name, to ensure the right function gets
 	 * replaced.
 	 */
 	nsp = get_namespace_name(proc->pronamespace);
-	appendStringInfo(&buf, "CREATE OR REPLACE FUNCTION %s(",
+	appendStringInfo(&buf, "CREATE OR REPLACE %s %s(",
+					 isfunction ? "FUNCTION" : "PROCEDURE",
 					 quote_qualified_identifier(nsp, name));
 	(void) print_function_arguments(&buf, proctup, false, true);
-	appendStringInfoString(&buf, ")\n RETURNS ");
-	print_function_rettype(&buf, proctup);
+	appendStringInfoString(&buf, ")\n");
+	if (isfunction)
+	{
+		appendStringInfoString(&buf, " RETURNS ");
+		print_function_rettype(&buf, proctup);
+		appendStringInfoChar(&buf, '\n');
+	}
 
 	print_function_trftypes(&buf, proctup);
 
-	appendStringInfo(&buf, "\n LANGUAGE %s\n",
+	appendStringInfo(&buf, " LANGUAGE %s\n",
 					 quote_identifier(get_language_name(proc->prolang, false)));
 
 	/* Emit some miscellaneous options on one line */
@@ -2607,10 +2616,11 @@ pg_get_functiondef(PG_FUNCTION_ARGS)
 	 *
 	 * Since the user is likely to be editing the function body string, we
 	 * shouldn't use a short delimiter that he might easily create a conflict
-	 * with.  Hence prefer "$function$", but extend if needed.
+	 * with.  Hence prefer "$function$"/"$procedure$", but extend if needed.
 	 */
 	initStringInfo(&dq);
-	appendStringInfoString(&dq, "$function");
+	appendStringInfoChar(&dq, '$');
+	appendStringInfoString(&dq, (isfunction ? "function" : "procedure"));
 	while (strstr(prosrc, dq.data) != NULL)
 		appendStringInfoChar(&dq, 'x');
 	appendStringInfoChar(&dq, '$');

src/test/regress/expected/create_procedure.out

@@ -30,6 +30,17 @@ CALL ptest1(substring(random()::text, 1, 1));  -- ok, volatile arg
  public | ptest1 |                  | x text              | proc
 (1 row)
 
+SELECT pg_get_functiondef('ptest1'::regproc);
+                pg_get_functiondef                 
+---------------------------------------------------
+ CREATE OR REPLACE PROCEDURE public.ptest1(x text)+
+  LANGUAGE sql                                    +
+ AS $procedure$                                   +
+ INSERT INTO cp_test VALUES (1, x);               +
+ $procedure$                                      +
+ 
+(1 row)
+
 SELECT * FROM cp_test ORDER BY b COLLATE "C";
  a |   b   
 ---+-------

src/test/regress/sql/create_procedure.sql

@@ -17,6 +17,7 @@ CALL ptest1('xy' || 'zzy');  -- ok, constant-folded arg
 CALL ptest1(substring(random()::text, 1, 1));  -- ok, volatile arg
 
 \df ptest1
+SELECT pg_get_functiondef('ptest1'::regproc);
 
 SELECT * FROM cp_test ORDER BY b COLLATE "C";