fix #804: minify of ".0" in css

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+* Fix minification of `.0` in CSS ([#804](https://github.com/evanw/esbuild/issues/804))
+
+    If you write `.0` instead of `0` in CSS and enabled `--minify`, esbuild would previously minify this token incorrectly (the token was deleted). This bug has been fixed and esbuild should now minify this token to `0`.
+
 ## 0.8.45
 
 * Add the `--servedir=` flag ([#796](https://github.com/evanw/esbuild/issues/796))

internal/css_parser/css_decls.go

@@ -650,11 +650,17 @@ func (p *parser) mangleColor(token css_ast.Token) css_ast.Token {
 			token.Kind = css_lexer.TFunction
 			token.Text = "rgba"
 			commaToken := p.commaToken()
+			alpha := floatToString(float64(hexA(hex)) / 255)
+			if p.options.MangleSyntax {
+				if text, ok := mangleNumber(alpha); ok {
+					alpha = text
+				}
+			}
 			token.Children = &[]css_ast.Token{
 				{Kind: css_lexer.TNumber, Text: strconv.Itoa(hexR(hex))}, commaToken,
 				{Kind: css_lexer.TNumber, Text: strconv.Itoa(hexG(hex))}, commaToken,
 				{Kind: css_lexer.TNumber, Text: strconv.Itoa(hexB(hex))}, commaToken,
-				{Kind: css_lexer.TNumber, Text: floatToString(float64(hexA(hex)) / 255)},
+				{Kind: css_lexer.TNumber, Text: alpha},
 			}
 		}
 	}

internal/css_parser/css_parser.go

@@ -673,6 +673,9 @@ func mangleNumber(t string) (string, bool) {
 		// Remove the decimal point if it's unnecessary
 		if dot+1 == len(t) {
 			t = t[:dot]
+			if t == "" || t == "+" || t == "-" {
+				t += "0"
+			}
 		} else {
 			// Remove a leading zero
 			if len(t) >= 3 && t[0] == '0' && t[1] == '.' && t[2] >= '0' && t[2] <= '9' {

internal/css_parser/css_parser_test.go

@@ -74,6 +74,14 @@ func expectPrintedMangle(t *testing.T, contents string, expected string) {
 	})
 }
 
+func expectPrintedLowerMangle(t *testing.T, contents string, expected string) {
+	t.Helper()
+	expectPrintedCommon(t, contents+" [mangle]", contents, expected, config.Options{
+		UnsupportedCSSFeatures: ^compat.CSSFeature(0),
+		MangleSyntax:           true,
+	})
+}
+
 func TestEscapes(t *testing.T) {
 	// TIdent
 	expectPrinted(t, "a { value: id\\65nt }", "a {\n  value: ident;\n}\n")
@@ -256,18 +264,46 @@ func TestString(t *testing.T) {
 
 func TestNumber(t *testing.T) {
 	for _, ext := range []string{"", "%", "px+"} {
+		expectPrinted(t, "a { width: .0"+ext+"; }", "a {\n  width: .0"+ext+";\n}\n")
+		expectPrinted(t, "a { width: .00"+ext+"; }", "a {\n  width: .00"+ext+";\n}\n")
+		expectPrinted(t, "a { width: .10"+ext+"; }", "a {\n  width: .10"+ext+";\n}\n")
 		expectPrinted(t, "a { width: 0."+ext+"; }", "a {\n  width: 0."+ext+";\n}\n")
+		expectPrinted(t, "a { width: 0.0"+ext+"; }", "a {\n  width: 0.0"+ext+";\n}\n")
 		expectPrinted(t, "a { width: 0.1"+ext+"; }", "a {\n  width: 0.1"+ext+";\n}\n")
+
+		expectPrinted(t, "a { width: +.0"+ext+"; }", "a {\n  width: +.0"+ext+";\n}\n")
+		expectPrinted(t, "a { width: +.00"+ext+"; }", "a {\n  width: +.00"+ext+";\n}\n")
+		expectPrinted(t, "a { width: +.10"+ext+"; }", "a {\n  width: +.10"+ext+";\n}\n")
 		expectPrinted(t, "a { width: +0."+ext+"; }", "a {\n  width: +0."+ext+";\n}\n")
+		expectPrinted(t, "a { width: +0.0"+ext+"; }", "a {\n  width: +0.0"+ext+";\n}\n")
 		expectPrinted(t, "a { width: +0.1"+ext+"; }", "a {\n  width: +0.1"+ext+";\n}\n")
+
+		expectPrinted(t, "a { width: -.0"+ext+"; }", "a {\n  width: -.0"+ext+";\n}\n")
+		expectPrinted(t, "a { width: -.00"+ext+"; }", "a {\n  width: -.00"+ext+";\n}\n")
+		expectPrinted(t, "a { width: -.10"+ext+"; }", "a {\n  width: -.10"+ext+";\n}\n")
 		expectPrinted(t, "a { width: -0."+ext+"; }", "a {\n  width: -0."+ext+";\n}\n")
+		expectPrinted(t, "a { width: -0.0"+ext+"; }", "a {\n  width: -0.0"+ext+";\n}\n")
 		expectPrinted(t, "a { width: -0.1"+ext+"; }", "a {\n  width: -0.1"+ext+";\n}\n")
 
+		expectPrintedMangle(t, "a { width: .0"+ext+"; }", "a {\n  width: 0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: .00"+ext+"; }", "a {\n  width: 0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: .10"+ext+"; }", "a {\n  width: .1"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: 0."+ext+"; }", "a {\n  width: 0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: 0.0"+ext+"; }", "a {\n  width: 0"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: 0.1"+ext+"; }", "a {\n  width: .1"+ext+";\n}\n")
+
+		expectPrintedMangle(t, "a { width: +.0"+ext+"; }", "a {\n  width: +0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: +.00"+ext+"; }", "a {\n  width: +0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: +.10"+ext+"; }", "a {\n  width: +.1"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: +0."+ext+"; }", "a {\n  width: +0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: +0.0"+ext+"; }", "a {\n  width: +0"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: +0.1"+ext+"; }", "a {\n  width: +.1"+ext+";\n}\n")
+
+		expectPrintedMangle(t, "a { width: -.0"+ext+"; }", "a {\n  width: -0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: -.00"+ext+"; }", "a {\n  width: -0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: -.10"+ext+"; }", "a {\n  width: -.1"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: -0."+ext+"; }", "a {\n  width: -0"+ext+";\n}\n")
+		expectPrintedMangle(t, "a { width: -0.0"+ext+"; }", "a {\n  width: -0"+ext+";\n}\n")
 		expectPrintedMangle(t, "a { width: -0.1"+ext+"; }", "a {\n  width: -.1"+ext+";\n}\n")
 	}
 }
@@ -430,6 +466,9 @@ func TestColorRGBA(t *testing.T) {
 	expectPrintedMangle(t, "a { color: rgba(1% 2% 3% / 50%) }", "a {\n  color: #0305087f;\n}\n")
 	expectPrintedMangle(t, "a { color: rgba(1%, 2%, 3%, 0.5) }", "a {\n  color: #03050880;\n}\n")
 	expectPrintedMangle(t, "a { color: rgba(1%, 2%, 3%, 50%) }", "a {\n  color: #0305087f;\n}\n")
+
+	expectPrintedLowerMangle(t, "a { color: rgb(1, 2, 3, 0.4) }", "a {\n  color: rgba(1, 2, 3, .4);\n}\n")
+	expectPrintedLowerMangle(t, "a { color: rgba(1, 2, 3, 40%) }", "a {\n  color: rgba(1, 2, 3, .4);\n}\n")
 }
 
 func TestColorHSLA(t *testing.T) {
@@ -444,6 +483,9 @@ func TestColorHSLA(t *testing.T) {
 
 	expectPrintedMangle(t, "a { color: hsl(30 25% 50% / 50%) }", "a {\n  color: #9f80607f;\n}\n")
 	expectPrintedMangle(t, "a { color: hsla(30 25% 50% / 50%) }", "a {\n  color: #9f80607f;\n}\n")
+
+	expectPrintedLowerMangle(t, "a { color: hsl(1, 2%, 3%, 0.4) }", "a {\n  color: rgba(8, 8, 7, .4);\n}\n")
+	expectPrintedLowerMangle(t, "a { color: hsla(1, 2%, 3%, 40%) }", "a {\n  color: rgba(8, 8, 7, .4);\n}\n")
 }
 
 func TestLowerColor(t *testing.T) {

internal/css_printer/css_printer.go

@@ -553,16 +553,6 @@ func (p *printer) printIdent(text string, mode identMode, whitespace trailingWhi
 	}
 }
 
-// TODO: Unify this with the numeric printing path in the JavaScript printer
-func (p *printer) printNumber(text string) {
-	// Remove the leading "0" from numbers starting with "0."
-	if p.RemoveWhitespace && len(text) > 2 && strings.HasPrefix(text, "0.") {
-		text = text[1:]
-	}
-
-	p.print(text)
-}
-
 func (p *printer) printIndent(indent int) {
 	for i := 0; i < indent; i++ {
 		p.sb.WriteString("  ")
@@ -595,15 +585,8 @@ func (p *printer) printTokens(tokens []css_ast.Token) bool {
 			p.printIdent(t.Text, identNormal, whitespace)
 			p.print("(")
 
-		case css_lexer.TNumber:
-			p.printNumber(t.Text)
-
-		case css_lexer.TPercentage:
-			p.printNumber(t.PercentValue())
-			p.print("%")
-
 		case css_lexer.TDimension:
-			p.printNumber(t.DimensionValue())
+			p.print(t.DimensionValue())
 			p.printIdent(t.DimensionUnit(), identDimensionUnit, whitespace)
 
 		case css_lexer.TAtKeyword:

internal/css_printer/css_printer_test.go

@@ -98,15 +98,6 @@ func TestURLQuote(t *testing.T) {
 	expectPrinted(t, "* { background: url('\"foo\"') }", "* {\n  background: url('\"foo\"');\n}\n")
 }
 
-func TestNumber(t *testing.T) {
-	expectPrinted(t, "div { opacity: 0.2 }", "div {\n  opacity: 0.2;\n}\n")
-	expectPrinted(t, "div { opacity: 0.2% }", "div {\n  opacity: 0.2%;\n}\n")
-	expectPrinted(t, "div { opacity: 0.2px }", "div {\n  opacity: 0.2px;\n}\n")
-	expectPrintedMinify(t, "div { opacity: 0.2 }", "div{opacity:.2}")
-	expectPrintedMinify(t, "div { opacity: 0.2% }", "div{opacity:.2%}")
-	expectPrintedMinify(t, "div { opacity: 0.2px }", "div{opacity:.2px}")
-}
-
 func TestImportant(t *testing.T) {
 	expectPrinted(t, "a { b: c!important }", "a {\n  b: c !important;\n}\n")
 	expectPrinted(t, "a { b: c!important; }", "a {\n  b: c !important;\n}\n")