Update error handling

CHANGELOG.md

@@ -1,2 +1,6 @@
+## v1.1.0
+- Use [`node.error`](https://github.com/postcss/postcss/blob/master/docs/guidelines/plugin.md#31-use-nodeerror-on-css-relevant-errors) for errors.
+- Correct readme for installing.
+
 ## v1.0.0
 - Initial release.

README.md

@@ -1,4 +1,4 @@
-# postcss-vertical-ryhthm [![Build Status][ci-img]][ci]
+# postcss-vertical-rhythm [![Build Status][ci-img]][ci]
 [PostCSS]: https://github.com/postcss/postcss
 [ci-img]:  https://travis-ci.org/markgoodyear/postcss-vertical-rhythm.svg?branch=master
 [ci]:      https://travis-ci.org/markgoodyear/postcss-vertical-rhythm
@@ -46,16 +46,15 @@ Default:
 ## Usage
 Install:
 ```
-npm install postcss-vertical-ryhthm --save-dev
+npm install postcss-vertical-rhythm --save-dev
 ```
 
 Then include the plugin:
 ```js
-postcss([ require('vertical-ryhthm')({ options }) ])
+postcss([ require('postcss-vertical-rhythm')(options) ])
 ```
 
 See [PostCSS] docs for examples for your environment.
 
-
 ## Licence
 Released under the MIT license.

index.js

@@ -1,5 +1,4 @@
 var postcss = require('postcss');
-var spacingValue;
 
 /**
  * Convert unit to unitless px value.
@@ -34,55 +33,56 @@ var calcLineHeight = function (fontProps) {
 
 /**
  * Gets the font declaration properties.
- * @param  {String} declValue
+ * @param  {Object} decl
  * @return {Array}
  */
-var getProps = function (declValue) {
+var getProps = function (decl) {
 
   // Matches {$1:font-size}{$2:unit}/{$3:line-height}.
-  var fontProps = declValue.match(/(\d+|\d+?\.\d+)(r?em|px|%)(?:\s*\/\s*)(\d+|\d+?\.\d+)\s+/);
+  var fontProps = decl.value.match(/(\d+|\d+?\.\d+)(r?em|px|%)(?:\s*\/\s*)(\d+|\d+?\.\d+)\s+/);
 
   // Make sure the line-height value is declared.
   if (!fontProps) {
-    throw new Error('Font declaration is invalid. Make sure line-height is set.');
+    throw decl.error('Font declaration is invalid. Make sure line-height is set.');
   }
 
   return fontProps;
 };
 
 /**
- * Gets the spacing value.
- * @param  {String} declValue
+ * Gets the rhythm value.
+ * @param  {Object} decl
  * @return {Number}
  */
-var getSpacingValue = function (declValue) {
-  var val = parseFloat(declValue) || 1;
+var getRhythmValue = function (decl, rhythmValue) {
+  var val = parseFloat(decl.value) || 1;
 
-  return spacingValue * val;
+  return rhythmValue * val;
 };
 
 module.exports = postcss.plugin('postcss-vertical-rhythm', function (opts) {
   opts = opts || {};
   var rootSelector = opts.rootSelector || 'body';
   var rhythmUnit = 'vr';
+  var rhythmValue;
 
   return function (css) {
     css.eachDecl(function transformDecl (decl) {
 
       // Check for root font-size.
       if (decl.parent.selector === rootSelector) {
         if (decl.prop === 'font') {
-          var props = getProps(decl.value);
+          var props = getProps(decl);
 
-          spacingValue = calcLineHeight(props);
+          rhythmValue = calcLineHeight(props);
         } else {
-          throw new Error('font declaration not found in ' + rootSelector);
+          throw decl.error('Font declaration not found in ' + rootSelector);
         }
       }
 
-      // Calculate spacing value.
+      // Calculate ryhthm value.
       if (decl.value.indexOf(rhythmUnit) !== -1) {
-        decl.value = getSpacingValue(decl.value) + 'px';
+        decl.value = getRhythmValue(decl, rhythmValue) + 'px';
       }
     });
   };

package.json

@@ -1,6 +1,6 @@
 {
   "name": "postcss-vertical-rhythm",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "description": "A PostCSS plugin to create a custom vertical rhythm unit from the base font-size and line-height.",
   "keywords": [
     "postcss",