Fix fuzz bug with background-position with three numbers; enable back…

…ground position minify with calc(); updates #263
tdewolff · Sep 5, 2019 · 1b5a2f7 · 1b5a2f7
1 parent 008ade2
commit 1b5a2f7
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Showing 2 changed files with 6 additions and 5 deletions.
diff --git a/css/css.go b/css/css.go
@@ -605,15 +605,15 @@ func (c *cssMinifier) minifyProperty(prop css.Hash, values []Token) []Token {
 
 			// background-position or background-size
 			// TODO: allow only functions that return Number, Percentage or Dimension token. Make whitelist?
-			if values[i].TokenType == css.NumberToken || values[i].TokenType == css.DimensionToken || values[i].TokenType == css.PercentageToken || values[i].TokenType == css.IdentToken && (h == css.Left || h == css.Right || h == css.Top || h == css.Bottom || h == css.Center) {
+			if values[i].TokenType == css.NumberToken || values[i].TokenType == css.DimensionToken || values[i].TokenType == css.PercentageToken || values[i].TokenType == css.IdentToken && (h == css.Left || h == css.Right || h == css.Top || h == css.Bottom || h == css.Center) || values[i].TokenType == css.FunctionToken && bytes.Equal(values[i].Data, []byte("calc(")) {
 				j := i + 1
 				for ; j < len(values); j++ {
 					if values[j].TokenType == css.IdentToken {
 						h := css.ToHash(values[j].Data)
 						if h == css.Left || h == css.Right || h == css.Top || h == css.Bottom || h == css.Center {
 							continue
 						}
-					} else if values[j].TokenType == css.NumberToken || values[j].TokenType == css.DimensionToken || values[j].TokenType == css.PercentageToken {
+					} else if values[j].TokenType == css.NumberToken || values[j].TokenType == css.DimensionToken || values[j].TokenType == css.PercentageToken || values[i].TokenType == css.FunctionToken && bytes.Equal(values[i].Data, []byte("calc(")) {
 						continue
 					}
 					break
@@ -655,7 +655,7 @@ func (c *cssMinifier) minifyProperty(prop css.Hash, values []Token) []Token {
 		if len(values) == 3 || len(values) == 4 {
 			// remove zero offsets
 			for _, i := range []int{len(values) - 1, 1} {
-				if values[i].TokenType == css.NumberToken && bytes.Equal(values[i].Data, []byte("0")) || values[i].TokenType == css.PercentageToken && bytes.Equal(values[i].Data, []byte("0%")) {
+				if 2 < len(values) && (values[i].TokenType == css.NumberToken && bytes.Equal(values[i].Data, []byte("0")) || values[i].TokenType == css.PercentageToken && bytes.Equal(values[i].Data, []byte("0%"))) {
 					values = append(values[:i], values[i+1:]...)
 				}
 			}

diff --git a/css/css_test.go b/css/css_test.go
@@ -58,6 +58,7 @@ func TestCSS(t *testing.T) {
 		{"input[type=\"\x00\"] {  a: b\n}.a{}", "input[type=\"\x00\"]{a:b}.a{}"},
 		{"a{a:)'''", "a{a:)'''}"},
 		{"{T:l(", "{t:l(}"},
+		{"{background:0 0 0", "{background:0 0}"},
 	}
 
 	m := minify.New()
@@ -159,7 +160,7 @@ func TestCSSInline(t *testing.T) {
 		{"background:#fff url(foo.svg) no-repeat right .75rem center / auto calc(100% - 1.5rem)", "background:#fff url(foo.svg) no-repeat right .75rem center/auto calc(100% - 1.5rem)"},
 		{"background:#fff / 5% auto", "background:#fff/5%"},
 		{"background:#fff / auto 5%", "background:#fff/auto 5%"},
-		//{"background:calc(5%-2%) center", "background:calc(5%-2%)"},
+		{"background:calc(5%-2%) center", "background:calc(5%-2%)"},
 		{"font-weight: bold; font-weight: normal;", "font-weight:700;font-weight:400"},
 		{"font: caption;", "font:caption"},
 		{"font: bold 5px \"Times new Roman\",\"Sans-Serif\";", "font:700 5px times new roman,sans-serif"},
@@ -257,7 +258,7 @@ func TestCSSInline(t *testing.T) {
 		{"margin: rgb((brackets));", "margin:rgb((brackets))"},
 
 		// bugs
-		//{"background: linear-gradient(-180deg, #355FFF 0%, #1F52FF 100%) 0% 0% / cover", "background: linear-gradient(-180deg, #355FFF 0%, #1F52FF 100%) 0% 0% / cover"}, // #263
+		{"background: linear-gradient(-180deg, #355FFF 0%, #1F52FF 100%) 0% 0% / cover", "background:linear-gradient(-180deg,#355FFF 0%,#1F52FF 100%) 0 0/cover"}, // #263
 
 		// go-fuzz
 		{"FONT-FAMILY: ru\"", "font-family:ru\""},