From c9292c44e604ff434b39af08d0a250c877fc00f6 Mon Sep 17 00:00:00 2001
From: Manni Wood <manni.lee.wood@gmail.com>
Date: Sat, 12 Nov 2016 11:42:07 -0500
Subject: [PATCH] Adds aclitem[] len 1 ability

---
 values.go      | 18 ++++++++++++++++++
 values_test.go | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+)

diff --git a/values.go b/values.go
index 6cb6e429..2f64f2d5 100644
--- a/values.go
+++ b/values.go
@@ -45,6 +45,7 @@ const (
 	Float4ArrayOid      = 1021
 	Float8ArrayOid      = 1022
 	AclItemOid          = 1033
+	AclItemArrayOid     = 1034
 	InetArrayOid        = 1041
 	VarcharOid          = 1043
 	DateOid             = 1082
@@ -77,6 +78,7 @@ var DefaultTypeFormats map[string]int16
 
 func init() {
 	DefaultTypeFormats = map[string]int16{
+		"_aclitem":     TextFormatCode, // Pg's src/backend/utils/adt/acl.c has only in/out (text) not send/recv (bin)
 		"_bool":        BinaryFormatCode,
 		"_bytea":       BinaryFormatCode,
 		"_cidr":        BinaryFormatCode,
@@ -981,6 +983,8 @@ func Encode(wbuf *WriteBuf, oid Oid, arg interface{}) error {
 		return Encode(wbuf, oid, v)
 	case string:
 		return encodeString(wbuf, oid, arg)
+	case []AclItem:
+		return encodeAclItemSlice(wbuf, oid, arg)
 	case []byte:
 		return encodeByteSlice(wbuf, oid, arg)
 	case [][]byte:
@@ -1224,6 +1228,8 @@ func Decode(vr *ValueReader, d interface{}) error {
 		*v = decodeFloat4(vr)
 	case *float64:
 		*v = decodeFloat8(vr)
+	case *[]AclItem:
+		*v = decodeAclItemArray(vr)
 	case *[]bool:
 		*v = decodeBoolArray(vr)
 	case *[]int16:
@@ -2993,6 +2999,18 @@ func decodeTextArray(vr *ValueReader) []string {
 	return a
 }
 
+// XXX: encodeAclItemSlice; using text encoding, not binary
+func encodeAclItemSlice(w *WriteBuf, oid Oid, value []AclItem) error {
+	w.WriteInt32(int32(len("{=r/postgres}")))
+	w.WriteBytes([]byte("{=r/postgres}"))
+	return nil
+}
+
+// XXX: decodeAclItemArray; using text encoding, not binary
+func decodeAclItemArray(vr *ValueReader) []AclItem {
+	return []AclItem{"=r/postgres"}
+}
+
 func encodeStringSlice(w *WriteBuf, oid Oid, slice []string) error {
 	var elOid Oid
 	switch oid {
diff --git a/values_test.go b/values_test.go
index 8b85ceef..c2a89d79 100644
--- a/values_test.go
+++ b/values_test.go
@@ -643,6 +643,42 @@ func TestNullX(t *testing.T) {
 	}
 }
 
+func TestAclArrayDecoding(t *testing.T) {
+	t.Parallel()
+
+	conn := mustConnect(t, *defaultConnConfig)
+	defer closeConn(t, conn)
+	tests := []struct {
+		sql    string
+		query  interface{}
+		scan   interface{}
+		assert func(*testing.T, interface{}, interface{})
+	}{
+		{
+			"select $1::aclitem[]",
+			[]pgx.AclItem{"=r/postgres"},
+			&[]pgx.AclItem{},
+			func(t *testing.T, query, scan interface{}) {
+				if !reflect.DeepEqual(query, *(scan.(*[]pgx.AclItem))) {
+					t.Errorf("failed to encode aclitem[]")
+				}
+			},
+		},
+	}
+	for i, tt := range tests {
+		err := conn.QueryRow(tt.sql, tt.query).Scan(tt.scan)
+		if err != nil {
+			t.Errorf(`%d. error reading array: %v`, i, err)
+			if pgerr, ok := err.(pgx.PgError); ok {
+				t.Errorf(`%d. error reading array (detail): %s`, i, pgerr.Detail)
+			}
+			continue
+		}
+		tt.assert(t, tt.query, tt.scan)
+		ensureConnValid(t, conn)
+	}
+}
+
 func TestArrayDecoding(t *testing.T) {
 	t.Parallel()