From c4b08378f235fdc9f8928f5f31316aff5602bfaf Mon Sep 17 00:00:00 2001
From: Jack Christensen <jack@jackchristensen.com>
Date: Sat, 5 Mar 2022 21:27:17 -0600
Subject: [PATCH] Handle driver.Valuers inside Map.Encode

---
 conn.go          | 28 +++++++---------------------
 pgtype/pgtype.go | 11 +++++++++++
 values.go        | 14 --------------
 3 files changed, 18 insertions(+), 35 deletions(-)

diff --git a/conn.go b/conn.go
index 20968892..9f2fdcf0 100644
--- a/conn.go
+++ b/conn.go
@@ -472,22 +472,17 @@ func (c *Conn) execSimpleProtocol(ctx context.Context, sql string, arguments []i
 	return commandTag, err
 }
 
-func (c *Conn) execParamsAndPreparedPrefix(sd *pgconn.StatementDescription, arguments []interface{}) error {
-	if len(sd.ParamOIDs) != len(arguments) {
-		return fmt.Errorf("expected %d arguments, got %d", len(sd.ParamOIDs), len(arguments))
+func (c *Conn) execParamsAndPreparedPrefix(sd *pgconn.StatementDescription, args []interface{}) error {
+	if len(sd.ParamOIDs) != len(args) {
+		return fmt.Errorf("expected %d arguments, got %d", len(sd.ParamOIDs), len(args))
 	}
 
 	c.eqb.Reset()
 
-	anynil.NormalizeSlice(arguments)
-
-	args, err := evaluateDriverValuers(arguments)
-	if err != nil {
-		return err
-	}
+	anynil.NormalizeSlice(args)
 
 	for i := range args {
-		err = c.eqb.AppendParam(c.typeMap, sd.ParamOIDs[i], args[i])
+		err := c.eqb.AppendParam(c.typeMap, sd.ParamOIDs[i], args[i])
 		if err != nil {
 			return err
 		}
@@ -675,11 +670,6 @@ optionLoop:
 	rows.sql = sd.SQL
 
 	anynil.NormalizeSlice(args)
-	args, err = evaluateDriverValuers(args)
-	if err != nil {
-		rows.fatal(err)
-		return rows, rows.err
-	}
 
 	for i := range args {
 		err = c.eqb.AppendParam(c.typeMap, sd.ParamOIDs[i], args[i])
@@ -836,13 +826,9 @@ func (c *Conn) SendBatch(ctx context.Context, b *Batch) BatchResults {
 		}
 
 		anynil.NormalizeSlice(bi.arguments)
-		args, err := evaluateDriverValuers(bi.arguments)
-		if err != nil {
-			return &batchResults{ctx: ctx, conn: c, err: err}
-		}
 
-		for i := range args {
-			err = c.eqb.AppendParam(c.typeMap, sd.ParamOIDs[i], args[i])
+		for i := range bi.arguments {
+			err := c.eqb.AppendParam(c.typeMap, sd.ParamOIDs[i], bi.arguments[i])
 			if err != nil {
 				return &batchResults{ctx: ctx, conn: c, err: err}
 			}
diff --git a/pgtype/pgtype.go b/pgtype/pgtype.go
index 3244b504..1cc809b1 100644
--- a/pgtype/pgtype.go
+++ b/pgtype/pgtype.go
@@ -1720,6 +1720,17 @@ func (m *Map) Encode(oid uint32, formatCode int16, value interface{}, buf []byte
 
 	plan := m.PlanEncode(oid, formatCode, value)
 	if plan == nil {
+		if dv, ok := value.(driver.Valuer); ok {
+			if dv == nil {
+				return nil, nil
+			}
+			v, err := dv.Value()
+			if err != nil {
+				return nil, err
+			}
+			return m.Encode(oid, formatCode, v, buf)
+		}
+
 		return nil, fmt.Errorf("unable to encode %#v into OID %d", value, oid)
 	}
 	return plan.Encode(value, buf)
diff --git a/values.go b/values.go
index 0f34b6a6..a3343d81 100644
--- a/values.go
+++ b/values.go
@@ -159,17 +159,3 @@ func stripNamedType(val *reflect.Value) (interface{}, bool) {
 
 	return nil, false
 }
-
-func evaluateDriverValuers(args []interface{}) ([]interface{}, error) {
-	for i, arg := range args {
-		switch arg := arg.(type) {
-		case driver.Valuer:
-			v, err := arg.Value()
-			if err != nil {
-				return nil, err
-			}
-			args[i] = v
-		}
-	}
-	return args, nil
-}