From 18fd30380d4bf6ac1a04b4c1dca3a120009d94e0 Mon Sep 17 00:00:00 2001
From: Taco de Wolff <tacodewolff@gmail.com>
Date: Thu, 28 Jan 2016 10:15:18 +0100
Subject: [PATCH] Minify numbers in meta viewport

Fixes #69, numbers are minified using the CSS specs
---
 html/html.go      | 15 +++++++++++++++
 html/html_test.go |  1 +
 2 files changed, 16 insertions(+)

diff --git a/html/html.go b/html/html.go
index efb538c59c..6ba6877bda 100644
--- a/html/html.go
+++ b/html/html.go
@@ -285,6 +285,21 @@ func (o *Minifier) Minify(m *minify.M, w io.Writer, r io.Reader, _ map[string]st
 								content.AttrVal = bytes.Replace(content.AttrVal, []byte(", "), []byte(","), -1)
 							} else if parse.EqualFold(name.AttrVal, []byte("viewport")) {
 								content.AttrVal = bytes.Replace(content.AttrVal, []byte(" "), []byte(""), -1)
+								for i := 0; i < len(content.AttrVal); i++ {
+									if content.AttrVal[i] == '=' && i+2 < len(content.AttrVal) {
+										i++
+										if n := parse.Number(content.AttrVal[i:]); n > 0 {
+											minNum := minify.Number(content.AttrVal[i : i+n])
+											if len(minNum) < n {
+												copy(content.AttrVal[i:i+len(minNum)], minNum)
+												copy(content.AttrVal[i+len(minNum):], content.AttrVal[i+n:])
+												content.AttrVal = content.AttrVal[:len(content.AttrVal)+len(minNum)-n]
+											}
+											i += len(minNum)
+										}
+										i-- // mitigate for-loop increase
+									}
+								}
 							}
 						}
 					}
diff --git a/html/html_test.go b/html/html_test.go
index c2715a8726..8b6151b515 100644
--- a/html/html_test.go
+++ b/html/html_test.go
@@ -53,6 +53,7 @@ func TestHTML(t *testing.T) {
 		{`<link href="data:text/plain, data">`, `<link href=data:,+data>`},
 		{`<svg width="100" height="100"><circle cx="50" cy="50" r="40" stroke="green" stroke-width="4" fill="yellow" /></svg>`, `<svg width=100 height=100><circle cx="50" cy="50" r="40" stroke="green" stroke-width="4" fill="yellow" /></svg>`},
 		{`</span >`, `</span>`},
+		{`<meta name=viewport content="width=0.1, initial-scale=1.0 , maximum-scale=1000">`, `<meta name=viewport content="width=.1,initial-scale=1,maximum-scale=1e3">`},
 
 		// increase coverage
 		{`<script style="css">js</script>`, `<script style=css>js</script>`},