codec: json: optimize bool encoding, and clean up bool decoding in na…

…ked mode
ugorji · Jan 9, 2023 · 2a1ab51 · 2a1ab51
1 parent a7b31a0
commit 2a1ab51
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Showing 3 changed files with 44 additions and 24 deletions.
diff --git a/codec/codec_test.go b/codec/codec_test.go
@@ -3570,7 +3570,7 @@ func doTestJsonDecodeNonStringScalarInStringContext(t *testing.T, h Handle) {
 	jh.SignedInteger = false
 
 	// Also test out decoding string values into naked interface
-	b = `{"true": true, "false": false, "null": null, "7700000000000000000": 7700000000000000000}`
+	b = `{"true": true, "false": false, null: null, "7700000000000000000": 7700000000000000000}`
 	const num = 7700000000000000000 // 77
 	var golden2 = map[interface{}]interface{}{
 		true:  true,

diff --git a/codec/helper.go b/codec/helper.go
@@ -2463,6 +2463,14 @@ func implIntf(rt, iTyp reflect.Type) (base bool, indir bool) {
 	return
 }
 
+func bool2int(b bool) (v uint8) {
+	// MARKER: optimized to be a single instruction
+	if b {
+		v = 1
+	}
+	return
+}
+
 func isSliceBoundsError(s string) bool {
 	return strings.Contains(s, "index out of range") ||
 		strings.Contains(s, "slice bounds out of range")

diff --git a/codec/json.go b/codec/json.go
@@ -80,6 +80,11 @@ const (
 	// Both technically valid JSON, but bomb on JSONP, so fix here unconditionally.
 	jsonEscapeMultiByteUnicodeSep = true
 
+	// jsonRecognizeBoolNullInQuotedStr is used during decoding into a blank interface{}
+	// to control whether we detect quoted values of bools and null where a map key is expected,
+	// and treat as nil, true or false.
+	jsonNakedBoolNullInQuotedStr = true
+
 	// jsonManualInlineDecRdInHotZones controls whether we manually inline some decReader calls.
 	//
 	// encode performance is at par with libraries that just iterate over bytes directly,
@@ -238,7 +243,7 @@ func (e *jsonEncDriver) WriteMapElemValue() {
 
 func (e *jsonEncDriver) EncodeNil() {
 	// We always encode nil as just null (never in quotes)
-	// so we can easily decode if a nil in the json streamie if initial token is n.
+	// so we can easily decode if a nil in the json stream ie if initial token is n.
 
 	e.e.encWr.writestr(jsonLits[jsonLitN : jsonLitN+4])
 }
@@ -276,26 +281,32 @@ func (e *jsonEncDriver) EncodeRawExt(re *RawExt) {
 	}
 }
 
-func (e *jsonEncDriver) EncodeBool(b bool) {
-	// Use writen with an array instead of writeb with a slice
-	// i.e. in place of e.e.encWr.writeb(jsonLiteralTrueQ)
-	//      OR jsonLiteralTrue, jsonLiteralFalse, jsonLiteralFalseQ, etc
-
-	if e.ks && e.e.c == containerMapKey {
-		if b {
-			e.e.encWr.writestr(jsonLits[jsonLitT-1 : jsonLitT+5])
-		} else {
-			e.e.encWr.writestr(jsonLits[jsonLitF-1 : jsonLitF+6])
-		}
-	} else {
-		if b {
-			e.e.encWr.writestr(jsonLits[jsonLitT : jsonLitT+4])
-		} else {
-			e.e.encWr.writestr(jsonLits[jsonLitF : jsonLitF+5])
-		}
-	}
+var jsonEncBoolStrs = [2][2]string{
+	{jsonLits[jsonLitF : jsonLitF+5], jsonLits[jsonLitT : jsonLitT+4]},
+	{jsonLits[jsonLitF-1 : jsonLitF+6], jsonLits[jsonLitT-1 : jsonLitT+5]},
 }
 
+func (e *jsonEncDriver) EncodeBool(b bool) {
+	e.e.encWr.writestr(
+		jsonEncBoolStrs[bool2int(e.ks && e.e.c == containerMapKey)%2][bool2int(b)%2])
+}
+
+// func (e *jsonEncDriver) EncodeBool(b bool) {
+// 	if e.ks && e.e.c == containerMapKey {
+// 		if b {
+// 			e.e.encWr.writestr(jsonLits[jsonLitT-1 : jsonLitT+5])
+// 		} else {
+// 			e.e.encWr.writestr(jsonLits[jsonLitF-1 : jsonLitF+6])
+// 		}
+// 	} else {
+// 		if b {
+// 			e.e.encWr.writestr(jsonLits[jsonLitT : jsonLitT+4])
+// 		} else {
+// 			e.e.encWr.writestr(jsonLits[jsonLitF : jsonLitF+5])
+// 		}
+// 	}
+// }
+
 func (e *jsonEncDriver) encodeFloat(f float64, bitsize, fmt byte, prec int8) {
 	var blen uint
 	if e.ks && e.e.c == containerMapKey {
@@ -1217,12 +1228,13 @@ func (d *jsonDecDriver) DecodeNaked() {
 	case '[':
 		z.v = valueTypeArray // don't consume. kInterfaceNaked will call ReadArrayStart
 	case '"':
-		// if a string, and MapKeyAsString, then try to decode it as a nil, bool or number first
+		// if a string, and MapKeyAsString, then try to decode it as a bool or number first
 		bs = d.dblQuoteStringAsBytes()
-		if len(bs) > 0 && d.d.c == containerMapKey && d.h.MapKeyAsString {
+		if jsonNakedBoolNullInQuotedStr &&
+			d.h.MapKeyAsString && len(bs) > 0 && d.d.c == containerMapKey {
 			switch string(bs) {
-			case "null":
-				z.v = valueTypeNil
+			// case "null": // nil is never quoted
+			// 	z.v = valueTypeNil
 			case "true":
 				z.v = valueTypeBool
 				z.b = true