HTML: add KeepQuotes option, fixes #276

Author: tdewolff

README.md

@@ -172,6 +172,7 @@ Options:
 - `KeepDefaultAttrVals` preserve default attribute values such as `<script type="application/javascript">`
 - `KeepDocumentTags` preserve `html`, `head` and `body` tags
 - `KeepEndTags` preserve all end tags
+- `KeepQuotes` preserve quotes around attribute values
 - `KeepWhitespace` preserve whitespace between inline tags but still collapse multiple whitespace characters into one
 
 After recent benchmarking and profiling it became really fast and minifies pages in the 10ms range, making it viable for on-the-fly minification.

cmd/minify/README.md

@@ -28,6 +28,7 @@ You can enable bash tab completion by using
           --html-keep-default-attrvals       Preserve default attribute values
           --html-keep-document-tags          Preserve html, head and body tags
           --html-keep-end-tags               Preserve all end tags
+          --html-keep-quotes                 Preserve quotes around attribute values
           --html-keep-whitespace             Preserve whitespace characters but still collapse multiple into one
       -l, --list                             List all accepted filetypes
           --match string                     Filename pattern matching using regular expressions

cmd/minify/main.go

@@ -106,6 +106,7 @@ func main() {
 	flag.BoolVar(&htmlMinifier.KeepDocumentTags, "html-keep-document-tags", false, "Preserve html, head and body tags")
 	flag.BoolVar(&htmlMinifier.KeepEndTags, "html-keep-end-tags", false, "Preserve all end tags")
 	flag.BoolVar(&htmlMinifier.KeepWhitespace, "html-keep-whitespace", false, "Preserve whitespace characters but still collapse multiple into one")
+	flag.BoolVar(&htmlMinifier.KeepQuotes, "html-keep-quotes", false, "Preserve quotes around attribute values")
 	flag.IntVar(&svgMinifier.Decimals, "svg-decimals", -1, "Number of decimals to preserve in numbers, -1 is all")
 	flag.BoolVar(&xmlMinifier.KeepWhitespace, "xml-keep-whitespace", false, "Preserve whitespace characters but still collapse multiple into one")
 	if err := flag.Parse(os.Args[1:]); err != nil {

html/html.go

@@ -38,6 +38,7 @@ type Minifier struct {
 	KeepDefaultAttrVals     bool
 	KeepDocumentTags        bool
 	KeepEndTags             bool
+	KeepQuotes              bool
 	KeepWhitespace          bool
 }
 
@@ -459,7 +460,7 @@ func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, _ map[string]st
 						isXML := attr.Hash == html.Vocab || attr.Hash == html.Typeof || attr.Hash == html.Property || attr.Hash == html.Resource || attr.Hash == html.Prefix || attr.Hash == html.Content || attr.Hash == html.About || attr.Hash == html.Rev || attr.Hash == html.Datatype || attr.Hash == html.Inlist
 
 						// no quotes if possible, else prefer single or double depending on which occurs more often in value
-						val = html.EscapeAttrVal(&attrByteBuffer, attr.AttrVal, val, isXML)
+						val = html.EscapeAttrVal(&attrByteBuffer, attr.AttrVal, val, o.KeepQuotes || isXML)
 						if _, err := w.Write(val); err != nil {
 							return err
 						}

html/html_test.go

@@ -271,6 +271,26 @@ func TestHTMLKeepWhitespace(t *testing.T) {
 	}
 }
 
+func TestHTMLKeepQuotes(t *testing.T) {
+	htmlTests := []struct {
+		html     string
+		expected string
+	}{
+		{`<p attr="test">`, `<p attr="test">`},
+	}
+
+	m := minify.New()
+	htmlMinifier := &Minifier{KeepQuotes: true}
+	for _, tt := range htmlTests {
+		t.Run(tt.html, func(t *testing.T) {
+			r := bytes.NewBufferString(tt.html)
+			w := &bytes.Buffer{}
+			err := htmlMinifier.Minify(m, w, r, nil)
+			test.Minify(t, tt.html, err, w.String(), tt.expected)
+		})
+	}
+}
+
 func TestHTMLURL(t *testing.T) {
 	htmlTests := []struct {
 		url      string