CSS: lowercase hex colors, closes #2139 (#2203)

src/clean-ast.js

@@ -74,6 +74,10 @@ function massageAST(ast) {
       newObj.value = newObj.value.replace(/ /g, "");
     }
 
+    if (ast.type === "value-word" && ast.isColor && ast.isHex) {
+      newObj.value = newObj.value.toLowerCase();
+    }
+
     // (TypeScript) Ignore `static` in `constructor(static p) {}`
     // and `export` in `constructor(export p) {}`
     if (

src/printer-postcss.js

@@ -317,6 +317,9 @@ function genericPrint(path, options, print) {
       return n.value;
     }
     case "value-word": {
+      if (n.isColor && n.isHex) {
+        return n.value.toLowerCase();
+      }
       return n.value;
     }
     case "value-colon": {

tests/css_color/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,20 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`hexcolor.css 1`] = `
+.foo {
+    color: #AAA;
+    -o-color: #fabcd3;
+    -webkit-color: #873;
+    -moz-color: #6bcdef;
+    -ms-color: #AAbbCC;
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.foo {
+  color: #aaa;
+  -o-color: #fabcd3;
+  -webkit-color: #873;
+  -moz-color: #6bcdef;
+  -ms-color: #aabbcc;
+}
+
+`;

tests/css_color/hexcolor.css

@@ -0,0 +1,7 @@
+.foo {
+    color: #AAA;
+    -o-color: #fabcd3;
+    -webkit-color: #873;
+    -moz-color: #6bcdef;
+    -ms-color: #AAbbCC;
+}

tests/css_color/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, { parser: "postcss" });

tests/stylefmt/color-hex-lowercase/__snapshots__/jsfmt.spec.js.snap

@@ -4,7 +4,7 @@ exports[`color-hex-lowercase.css 1`] = `
 .foo{color:#ABCDEF}
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 .foo {
-  color: #ABCDEF;
+  color: #abcdef;
 }
 
 `;