Keep the xmlns:svg namespace, see #803

Author: tdewolff

svg/svg.go

@@ -14,14 +14,15 @@ import (
 )
 
 var (
-	voidBytes     = []byte("/>")
-	isBytes       = []byte("=")
-	spaceBytes    = []byte(" ")
-	cdataEndBytes = []byte("]]>")
-	zeroBytes     = []byte("0")
-	cssMimeBytes  = []byte("text/css")
-	noneBytes     = []byte("none")
-	urlBytes      = []byte("url(")
+	voidBytes        = []byte("/>")
+	isBytes          = []byte("=")
+	spaceBytes       = []byte(" ")
+	cdataEndBytes    = []byte("]]>")
+	zeroBytes        = []byte("0")
+	svgStartTagBytes = []byte("<svg")
+	cssMimeBytes     = []byte("text/css")
+	noneBytes        = []byte("none")
+	urlBytes         = []byte("url(")
 )
 
 ////////////////////////////////////////////////////////////////
@@ -129,9 +130,13 @@ func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, params map[stri
 			tag = t.Hash
 			if tag == Metadata {
 				t.Data = nil
-			} else if colon := bytes.IndexByte(t.Text, ':'); colon != -1 || t.Data == nil {
+			} else if colon := bytes.IndexByte(t.Data, ':'); colon != -1 {
 				// skip attributes in namespace (eg. inkscape or sodipodi)
-				t.Data = nil
+				if bytes.Equal(t.Data[:colon], svgStartTagBytes) {
+					t.Data = append(t.Data[:1], t.Data[5:]...)
+				} else {
+					t.Data = nil
+				}
 			} else if tag == Defs && tb.Peek(1).TokenType == xml.StartTagCloseVoidToken {
 				// skip empty tags
 				t.Data = nil

svg/svg_test.go

@@ -61,6 +61,8 @@ func TestSVG(t *testing.T) {
 		{`<foreignObject>`, `<foreignObject>`},
 		{`<foreignObject/>  text`, `<foreignObject/>text`},
 		{`<foreignObject><foreignObject/></foreignObject>  text`, `<foreignObject><foreignObject/></foreignObject>text`},
+		{`<xyz:rect width="100%" height="100%" fill="green"/>`, ``},
+		{`<svg:rect width="100%" height="100%" fill="green"/>`, `<rect width="100%" height="100%" fill="green"/>`},
 
 		// from SVGO
 		{`<!DOCTYPE bla><?xml?><!-- comment --><metadata/>`, ``},