feat: optimise generic decodes (#349)

codec.go

@@ -86,13 +86,13 @@ func decoderOfType(cfg *frozenConfig, schema Schema, typ reflect2.Type) ValDecod
 	// Handle eface case when it isnt a union
 	if typ.Kind() == reflect.Interface && schema.Type() != Union {
 		if _, ok := typ.(*reflect2.UnsafeIFaceType); !ok {
-			return &efaceDecoder{schema: schema}
+			return newEfaceDecoder(cfg, schema)
 		}
 	}
 
 	switch schema.Type() {
 	case String, Bytes, Int, Long, Float, Double, Boolean:
-		return createDecoderOfNative(schema, typ)
+		return createDecoderOfNative(schema.(*PrimitiveSchema), typ)
 
 	case Record:
 		return createDecoderOfRecord(cfg, schema, typ)

codec_dynamic.go

@@ -9,31 +9,43 @@ import (
 
 type efaceDecoder struct {
 	schema Schema
+	typ    reflect2.Type
+	dec    ValDecoder
+}
+
+func newEfaceDecoder(cfg *frozenConfig, schema Schema) *efaceDecoder {
+	typ, _ := genericReceiver(schema)
+	dec := decoderOfType(cfg, schema, typ)
+
+	return &efaceDecoder{
+		schema: schema,
+		typ:    typ,
+		dec:    dec,
+	}
 }
 
 func (d *efaceDecoder) Decode(ptr unsafe.Pointer, r *Reader) {
 	pObj := (*any)(ptr)
-	obj := *pObj
-	if obj == nil {
-		*pObj = genericDecode(d.schema, r)
+	if *pObj == nil {
+		*pObj = genericDecode(d.typ, d.dec, r)
 		return
 	}
 
-	typ := reflect2.TypeOf(obj)
+	typ := reflect2.TypeOf(*pObj)
 	if typ.Kind() != reflect.Ptr {
-		*pObj = genericDecode(d.schema, r)
+		*pObj = genericDecode(d.typ, d.dec, r)
 		return
 	}
 
 	ptrType := typ.(*reflect2.UnsafePtrType)
 	ptrElemType := ptrType.Elem()
-	if reflect2.IsNil(obj) {
+	if reflect2.IsNil(*pObj) {
 		obj := ptrElemType.New()
 		r.ReadVal(d.schema, obj)
 		*pObj = obj
 		return
 	}
-	r.ReadVal(d.schema, obj)
+	r.ReadVal(d.schema, *pObj)
 }
 
 type interfaceEncoder struct {

codec_generic.go

@@ -1,140 +1,138 @@
 package avro
 
 import (
-	"fmt"
+	"errors"
 	"math/big"
 	"time"
-	"unsafe"
 
 	"github.com/modern-go/reflect2"
 )
 
-func genericDecode(schema Schema, r *Reader) any {
-	rPtr, rTyp, err := genericReceiver(schema)
-	if err != nil {
-		r.ReportError("Read", err.Error())
-		return nil
-	}
-	decoderOfType(r.cfg, schema, rTyp).Decode(rPtr, r)
+func genericDecode(typ reflect2.Type, dec ValDecoder, r *Reader) any {
+	ptr := typ.UnsafeNew()
+	dec.Decode(ptr, r)
 	if r.Error != nil {
 		return nil
 	}
-	obj := rTyp.UnsafeIndirect(rPtr)
+
+	obj := typ.UnsafeIndirect(ptr)
 	if reflect2.IsNil(obj) {
 		return nil
 	}
 
 	// Generic reader returns a different result from the
 	// codec in the case of a big.Rat. Handle this.
-	if rTyp.Type1() == ratType {
+	if typ.Type1() == ratType {
 		dec := obj.(big.Rat)
 		return &dec
 	}
-
 	return obj
 }
 
-func genericReceiver(schema Schema) (unsafe.Pointer, reflect2.Type, error) {
+func genericReceiver(schema Schema) (reflect2.Type, error) {
+	if schema.Type() == Ref {
+		schema = schema.(*RefSchema).Schema()
+	}
+
 	var ls LogicalSchema
 	lts, ok := schema.(LogicalTypeSchema)
 	if ok {
 		ls = lts.Logical()
 	}
 
-	name := string(schema.Type())
+	schemaName := string(schema.Type())
 	if ls != nil {
-		name += "." + string(ls.Type())
+		schemaName += "." + string(ls.Type())
 	}
 
 	switch schema.Type() {
 	case Boolean:
 		var v bool
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Int:
 		if ls != nil {
 			switch ls.Type() {
 			case Date:
 				var v time.Time
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 
 			case TimeMillis:
 				var v time.Duration
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			}
 		}
 		var v int
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Long:
 		if ls != nil {
 			switch ls.Type() {
 			case TimeMicros:
 				var v time.Duration
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			case TimestampMillis:
 				var v time.Time
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			case TimestampMicros:
 				var v time.Time
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			case LocalTimestampMillis:
 				var v time.Time
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			case LocalTimestampMicros:
 				var v time.Time
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			}
 		}
 		var v int64
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Float:
 		var v float32
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Double:
 		var v float64
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case String:
 		var v string
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Bytes:
 		if ls != nil && ls.Type() == Decimal {
 			var v *big.Rat
-			return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+			return reflect2.TypeOf(v), nil
 		}
 		var v []byte
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Record:
 		var v map[string]any
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
-	case Ref:
-		return genericReceiver(schema.(*RefSchema).Schema())
+		return reflect2.TypeOf(v), nil
 	case Enum:
 		var v string
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Array:
 		v := make([]any, 0)
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Map:
 		var v map[string]any
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Union:
 		var v map[string]any
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	case Fixed:
 		fixed := schema.(*FixedSchema)
 		ls := fixed.Logical()
 		if ls != nil {
 			switch ls.Type() {
 			case Duration:
 				var v LogicalDuration
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			case Decimal:
 				var v big.Rat
-				return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+				return reflect2.TypeOf(v), nil
 			}
 		}
 		v := byteSliceToArray(make([]byte, fixed.Size()), fixed.Size())
-		return unsafe.Pointer(&v), reflect2.TypeOf(v), nil
+		return reflect2.TypeOf(v), nil
 	default:
-		return nil, nil, fmt.Errorf("dynamic receiver not found for schema: %v", name)
+		// This should not be possible.
+		return nil, errors.New("dynamic receiver not found for schema " + schemaName)
 	}
 }

codec_generic_internal_test.go

@@ -213,22 +213,27 @@ func TestGenericDecode(t *testing.T) {
 	for _, test := range tests {
 		test := test
 		t.Run(test.name, func(t *testing.T) {
+			defer ConfigTeardown()
+
 			schema := MustParse(test.schema)
 			r := NewReader(bytes.NewReader(test.data), 10)
 
-			got := genericDecode(schema, r)
+			typ, err := genericReceiver(schema)
+			require.NoError(t, err)
+			dec := decoderOfType(DefaultConfig.(*frozenConfig), schema, typ)
+
+			got := genericDecode(typ, dec, r)
 
 			test.wantErr(t, r.Error)
 			assert.Equal(t, test.want, got)
 		})
 	}
 }
 
-func TestGenericDecode_UnsupportedType(t *testing.T) {
+func TestGenericReceiver_UnsupportedType(t *testing.T) {
 	schema := NewPrimitiveSchema(Type("test"), nil)
-	r := NewReader(bytes.NewReader([]byte{0x01}), 10)
 
-	_ = genericDecode(schema, r)
+	_, err := genericReceiver(schema)
 
-	assert.Error(t, r.Error)
+	assert.Error(t, err)
 }