WIP pretty printing support

doc/src/sgml/func/func-info.sgml

@@ -3827,8 +3827,9 @@ acl      | {postgres=arwdDxtm/postgres,foo=r/postgres}
         <indexterm>
          <primary>pg_get_domain_ddl</primary>
         </indexterm>
-        <function>pg_get_domain_ddl</function> ( <parameter>domain</parameter> <type>text</type> )
-        <returnvalue>regtype</returnvalue>
+        <function>pg_get_domain_ddl</function> ( <parameter>domain</parameter> <type>regtype</type>
+         <optional> <parameter>pretty</parameter> <type>boolean</type> </optional>)
+        <returnvalue>text</returnvalue>
        </para>
        <para>
         Reconstructs the creating command for a domain.

src/backend/catalog/system_functions.sql

@@ -657,6 +657,12 @@ LANGUAGE INTERNAL
 STRICT VOLATILE PARALLEL UNSAFE
 AS 'pg_replication_origin_session_setup';
 
+CREATE OR REPLACE FUNCTION
+ pg_get_domain_ddl(domain_name regtype, pretty bool DEFAULT false)
+ RETURNS text
+ LANGUAGE internal
+AS 'pg_get_domain_ddl_ext';
+
 --
 -- The default permissions for functions mean that anyone can execute them.
 -- A number of functions shouldn't be executable by just anyone, but rather

src/backend/utils/adt/ruleutils.c

@@ -94,6 +94,10 @@
 	((pretty) ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) \
 	 : PRETTYFLAG_INDENT)
 
+#define GET_DDL_PRETTY_FLAGS(pretty) \
+	((pretty) ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) \
+	: 0)
+
 /* Default line length for pretty-print wrapping: 0 means wrap always */
 #define WRAP_COLUMN_DEFAULT		0
 
@@ -546,6 +550,11 @@ static void get_json_table_nested_columns(TableFunc *tf, JsonTablePlan *plan,
 										  deparse_context *context,
 										  bool showimplicit,
 										  bool needcomma);
+static void get_formatted_string(StringInfo buf,
+								 int prettyFlags,
+								 int noOfTabChars,
+								 const char *fmt,...) pg_attribute_printf(4, 5);
+static char *pg_get_domain_ddl_worker(Oid domain_oid, int prettyFlags);
 
 #define only_marker(rte)  ((rte)->inh ? "" : "ONLY ")
 
@@ -13739,6 +13748,37 @@ get_range_partbound_string(List *bound_datums)
 	return buf->data;
 }
 
+/*
+ * get_formatted_string
+ *
+ * Return a formatted version of the string.
+ *
+ * pretty - If pretty is true, the output includes tabs (\t) and newlines (\n).
+ * noOfTabChars - indent with specified no of tabs.
+ * fmt - printf-style format string used by appendStringInfoVA.
+ */
+static void
+get_formatted_string(StringInfo buf, int prettyFlags, int noOfTabChars, const char *fmt,...)
+{
+	va_list		args;
+
+	if (prettyFlags & PRETTYFLAG_INDENT)
+	{
+		appendStringInfoChar(buf, '\n');
+		/* Indent with tabs */
+		for (int i = 0; i < noOfTabChars; i++)
+		{
+			appendStringInfoChar(buf, '\t');
+		}
+	}
+	else
+		appendStringInfoChar(buf, ' ');
+
+	va_start(args, fmt);
+	appendStringInfoVA(buf, fmt, args);
+	va_end(args);
+}
+
 
 /*
  * Helper function to scan domain constraints
@@ -13787,7 +13827,7 @@ scan_domain_constraints(Oid domain_oid, List **validcons, List **invalidcons)
  */
 static void
 build_create_domain_statement(StringInfo buf, Form_pg_type typForm,
-							 Node *defaultExpr, List *validConstraints)
+							  Node *defaultExpr, List *validConstraints, int prettyFlags)
 {
 	HeapTuple	baseTypeTuple;
 	Form_pg_type baseTypeForm;
@@ -13814,16 +13854,17 @@ build_create_domain_statement(StringInfo buf, Form_pg_type typForm,
 		/* Only add COLLATE if domain's collation differs from base type's */
 		if (typForm->typcollation != baseCollation)
 		{
-			appendStringInfo(buf, " COLLATE %s",
-							 generate_collation_name(typForm->typcollation));
+			get_formatted_string(buf, prettyFlags, 1, "COLLATE %s",
+								 generate_collation_name(typForm->typcollation));
 		}
 	}
 
 	/* Add default value if present */
 	if (defaultExpr != NULL)
 	{
-		char *defaultValue = deparse_expression_pretty(defaultExpr, NIL, false, false, 0, 0);
-		appendStringInfo(buf, " DEFAULT %s", defaultValue);
+		char	   *defaultValue = deparse_expression_pretty(defaultExpr, NIL, false, false, prettyFlags, 0);
+
+		get_formatted_string(buf, prettyFlags, 1, "DEFAULT %s", defaultValue);
 	}
 
 	/* Add valid constraints */
@@ -13837,14 +13878,14 @@ build_create_domain_statement(StringInfo buf, Form_pg_type typForm,
 		/* Look up the constraint info */
 		constraintTup = SearchSysCache1(CONSTROID, ObjectIdGetDatum(constraintOid));
 		if (!HeapTupleIsValid(constraintTup))
-			continue;	/* constraint was dropped concurrently */
+			continue;			/* constraint was dropped concurrently */
 
 		con = (Form_pg_constraint) GETSTRUCT(constraintTup);
-		constraintDef = pg_get_constraintdef_worker(constraintOid, false, PRETTYFLAG_PAREN, true);
+		constraintDef = pg_get_constraintdef_worker(constraintOid, false, prettyFlags, true);
 
-		appendStringInfo(buf, " CONSTRAINT %s %s",
-						 quote_identifier(NameStr(con->conname)),
-						 constraintDef);
+		get_formatted_string(buf, prettyFlags, 1, "CONSTRAINT %s",
+							 quote_identifier(NameStr(con->conname)));
+		get_formatted_string(buf, prettyFlags, 2, "%s", constraintDef);
 
 		ReleaseSysCache(constraintTup);
 	}
@@ -13856,28 +13897,45 @@ build_create_domain_statement(StringInfo buf, Form_pg_type typForm,
  * Helper function to add ALTER DOMAIN statements for invalid constraints
  */
 static void
-add_alter_domain_statements(StringInfo buf, List *invalidConstraints)
+add_alter_domain_statements(StringInfo buf, List *invalidConstraints, int prettyFlags)
 {
-	ListCell *lc;
+	ListCell   *lc;
 
 	foreach(lc, invalidConstraints)
 	{
-		Oid constraintOid = lfirst_oid(lc);
-		char *alterStmt = pg_get_constraintdef_worker(constraintOid, true, PRETTYFLAG_PAREN, true);
+		Oid			constraintOid = lfirst_oid(lc);
+		char	   *alterStmt = pg_get_constraintdef_worker(constraintOid, true, prettyFlags, true);
 
 		if (alterStmt)
 			appendStringInfo(buf, "\n%s;", alterStmt);
 	}
 }
 
 /*
- * pg_get_domain_ddl - Get CREATE DOMAIN statement for a domain
+ * pg_get_domain_ddl_ext - Get CREATE DOMAIN statement for a domain with pretty-print option
  */
 Datum
-pg_get_domain_ddl(PG_FUNCTION_ARGS)
+pg_get_domain_ddl_ext(PG_FUNCTION_ARGS)
 {
-	StringInfoData buf;
 	Oid			domain_oid = PG_GETARG_OID(0);
+	bool		pretty = PG_GETARG_BOOL(1);
+	char	   *res;
+	int			prettyFlags;
+
+	prettyFlags = GET_DDL_PRETTY_FLAGS(pretty);
+
+	res = pg_get_domain_ddl_worker(domain_oid, prettyFlags);
+	if (res == NULL)
+		PG_RETURN_NULL();
+	PG_RETURN_TEXT_P(string_to_text(res));
+}
+
+
+
+static char *
+pg_get_domain_ddl_worker(Oid domain_oid, int prettyFlags)
+{
+	StringInfoData buf;
 	HeapTuple	typeTuple;
 	Form_pg_type typForm;
 	Node	   *defaultExpr;
@@ -13887,7 +13945,7 @@ pg_get_domain_ddl(PG_FUNCTION_ARGS)
 	/* Look up the domain in pg_type */
 	typeTuple = SearchSysCache1(TYPEOID, ObjectIdGetDatum(domain_oid));
 	if (!HeapTupleIsValid(typeTuple))
-		PG_RETURN_NULL();
+		return NULL;
 
 	typForm = (Form_pg_type) GETSTRUCT(typeTuple);
 
@@ -13899,16 +13957,16 @@ pg_get_domain_ddl(PG_FUNCTION_ARGS)
 
 	/* Build the DDL statement */
 	initStringInfo(&buf);
-	build_create_domain_statement(&buf, typForm, defaultExpr, validConstraints);
+	build_create_domain_statement(&buf, typForm, defaultExpr, validConstraints, prettyFlags);
 
 	/* Add ALTER DOMAIN statements for invalid constraints */
 	if (list_length(invalidConstraints) > 0)
-		add_alter_domain_statements(&buf, invalidConstraints);
+		add_alter_domain_statements(&buf, invalidConstraints, prettyFlags);
 
 	/* Cleanup */
 	list_free(validConstraints);
 	list_free(invalidConstraints);
 	ReleaseSysCache(typeTuple);
 
-	PG_RETURN_TEXT_P(cstring_to_text(buf.data));
+	return buf.data;
 }

src/include/catalog/pg_proc.dat

@@ -8515,9 +8515,9 @@
 { oid => '2508', descr => 'constraint description with pretty-print option',
   proname => 'pg_get_constraintdef', provolatile => 's', prorettype => 'text',
   proargtypes => 'oid bool', prosrc => 'pg_get_constraintdef_ext' },
-{ oid => '8024', descr => 'get CREATE statement for DOMAIN',
+{ oid => '8024', descr => 'get CREATE statement for DOMAIN with pretty option',
   proname => 'pg_get_domain_ddl', prorettype => 'text',
-  proargtypes => 'regtype', prosrc => 'pg_get_domain_ddl' },
+  proargtypes => 'regtype bool', prosrc => 'pg_get_domain_ddl_ext' },
 { oid => '2509',
   descr => 'deparse an encoded expression with pretty-print option',
   proname => 'pg_get_expr', provolatile => 's', prorettype => 'text',