JS: revert transformation of => , fixes #863

Author: tdewolff

js/js.go

@@ -1013,13 +1013,14 @@ func (m *jsMinifier) minifyExpr(i js.IExpr, prec js.OpPrec) {
 									m.minifyExpr(left, js.OpUnary)
 									break
 								}
-							} else if right.Op == js.AddToken || right.Op == js.SubToken || right.Op == js.MulToken || right.Op == js.DivToken || right.Op == js.ModToken || right.Op == js.ExpToken || right.Op == js.LtLtToken || right.Op == js.GtGtToken || right.Op == js.GtGtGtToken || right.Op == js.BitAndToken || right.Op == js.BitOrToken || right.Op == js.BitXorToken || right.Op == js.AndToken || right.Op == js.OrToken || right.Op == js.NullishToken {
-								// a=a+b  =>  a+=b
-								m.minifyExpr(left, js.OpLHS)
-								m.write(right.Op.Bytes())
-								m.write(equalBytes)
-								m.minifyExpr(y, js.OpAssign)
-								break
+								// TODO: may break implicit "evaluation" of variables? see #863
+								//} else if right.Op == js.AddToken || right.Op == js.SubToken || right.Op == js.MulToken || right.Op == js.DivToken || right.Op == js.ModToken || right.Op == js.ExpToken || right.Op == js.LtLtToken || right.Op == js.GtGtToken || right.Op == js.GtGtGtToken || right.Op == js.BitAndToken || right.Op == js.BitOrToken || right.Op == js.BitXorToken {
+								//	// a=a+b  =>  a+=b
+								//	m.minifyExpr(left, js.OpLHS)
+								//	m.write(right.Op.Bytes())
+								//	m.write(equalBytes)
+								//	m.minifyExpr(y, js.OpAssign)
+								//	break
 							}
 						}
 					}

js/js_test.go

@@ -475,10 +475,10 @@ func TestJS(t *testing.T) {
 		{`a=false**2`, `a=(!1)**2`},
 		{`a=(++b)**2`, `a=++b**2`},
 		{`a=(a||b)&&c`, `a=(a||b)&&c`},
-		{`a=a||(b&&c)`, `a||=b&&c`},
+		//{`a=a||(b&&c)`, `a||=b&&c`},
 		{`a=(a&&b)||c`, `a=a&&b||c`},
-		{`a=a&&(b||c)`, `a&&=b||c`},
-		{`a=a&&(b&&c)`, `a&&=b&&c`},
+		//{`a=a&&(b||c)`, `a&&=b||c`},
+		//{`a=a&&(b&&c)`, `a&&=b&&c`},
 		{`a=c&&(a??b)`, `a=c&&(a??b)`},
 		{`a=(a||b)??(c||d)`, `a=(a||b)??(c||d)`},
 		{`a=(a&&b)??(c&&d)`, `a=(a&&b)??(c&&d)`},
@@ -678,10 +678,10 @@ func TestJS(t *testing.T) {
 		//{`(a.b===null||a.b===undefined)?undefined:a.b()`, `a.b?.()`},
 		{`a=1+a`, `++a`},
 		{`a=a-1`, `--a`},
-		{`a=a+5`, `a+=5`},
-		{`a=5+a`, `a+=5`},
-		{`a=a+b`, `a+=b`},
-		{`a=a^b`, `a^=b`},
+		//{`a=a+5`, `a+=5`},
+		//{`a=5+a`, `a+=5`},
+		//{`a=a+b`, `a+=b`},
+		//{`a=a^b`, `a^=b`},
 
 		// other
 		{`async function g(){await x+y}`, `async function g(){await x+y}`},

js/util.go

@@ -1383,7 +1383,10 @@ func decimalNumber(num []byte, prec int) []byte {
 func binaryNumber(num []byte, prec int) []byte {
 	b, suffix := removeUnderscoresAndSuffix(num)
 	if len(b) <= 2 || 65 < len(b) {
-		return num
+		if suffix {
+			return append(b, 'n')
+		}
+		return b
 	}
 	var n int64
 	for _, c := range b[2:] {
@@ -1406,7 +1409,10 @@ func binaryNumber(num []byte, prec int) []byte {
 func octalNumber(num []byte, prec int) []byte {
 	b, suffix := removeUnderscoresAndSuffix(num)
 	if len(b) <= 2 || 23 < len(b) {
-		return num
+		if suffix {
+			return append(b, 'n')
+		}
+		return b
 	}
 	var n int64
 	for _, c := range b[2:] {
@@ -1429,7 +1435,10 @@ func octalNumber(num []byte, prec int) []byte {
 func hexadecimalNumber(num []byte, prec int) []byte {
 	b, suffix := removeUnderscoresAndSuffix(num)
 	if len(b) <= 2 || 12 < len(b) || len(b) == 12 && ('D' < b[2] && b[2] <= 'F' || 'd' < b[2]) {
-		return num
+		if suffix {
+			return append(b, 'n')
+		}
+		return b
 	}
 	var n int64
 	for _, c := range b[2:] {