Add mediaQueries option

Author: jamiebuilds

CHANGELOG.md

@@ -1,4 +1,4 @@
-- Added: support for `@media` queries
+- Added: "mediaQueries" option for `@media` support
 
 # 5.1.0 - 2016-01-07
 

README.md

@@ -118,6 +118,17 @@ var out = postcss()
   .css
 ```
 
+#### `mediaQueries` (default: `false`)
+
+Allows calc() usage as part of media query declarations.
+
+```js
+var out = postcss()
+  .use(calc({mediaQueries: true}))
+  .process(css)
+  .css
+```
+
 ---
 
 ## Contributing

index.js

@@ -15,6 +15,7 @@ module.exports = postcss.plugin("postcss-calc", function(options) {
   var precision = options.precision
   var preserve = options.preserve
   var warnWhenCannotResolve = options.warnWhenCannotResolve
+  var mediaQueries = options.mediaQueries
 
   return function(style, result) {
     function transformValue(node, property) {
@@ -46,7 +47,7 @@ module.exports = postcss.plugin("postcss-calc", function(options) {
     }
 
     style.walk(function(rule) {
-      if (rule.type === "atrule") {
+      if (mediaQueries && rule.type === "atrule") {
         return transformValue(rule, "params")
       }
       else if (rule.type === "decl") {

test/fixtures/calc.css

@@ -18,3 +18,7 @@ stuff {
   prefixed-unresolved: -webkit-calc(var(--gutter-y) - 1px);
   z-index: calc(var(--zIndexThing) + 1);
 }
+
+@media (min-width: calc(10px + 10px)) {
+  .mediaQueriesShouldBeDisabledByDefault {}
+}

test/fixtures/calc.expected.css

@@ -6,3 +6,7 @@ stuff {
   prefixed-unresolved: -webkit-calc(1.125rem - 1px);
   z-index: 111;
 }
+
+@media (min-width: calc(10px + 10px)) {
+  .mediaQueriesShouldBeDisabledByDefault {}
+}

test/index.js

@@ -45,7 +45,7 @@ test("calc", function(t) {
   compareFixtures(
     t,
     "media",
-    {},
+    {mediaQueries: true},
     "should resolve media queries"
   )
 
@@ -67,7 +67,7 @@ test("calc", function(t) {
   compareFixtures(
     t,
     "preserve-media",
-    {preserve: true},
+    {preserve: true, mediaQueries: true},
     "should have a preserve option that allow to keep original calc() usage" +
     "with media"
   )