Refactored rules

rules/util.js

@@ -0,0 +1,28 @@
+function isGoogCallExpression(node, name) {
+  const callee = node.callee;
+  return callee && callee.type === 'MemberExpression' &&
+      callee.object.type === 'Identifier' && callee.object.name === 'goog' &&
+      callee.property.type === 'Identifier' && !callee.property.computed &&
+      callee.property.name === name;
+}
+
+function isGoogStatement(node, name) {
+  return node.expression && node.expression.type === 'CallExpression' &&
+    isGoogCallExpression(node.expression, name);
+}
+
+exports.isProvideExpression = function(node) {
+  return isGoogCallExpression(node, 'provide');
+};
+
+exports.isProvideStatement = function(node) {
+  return isGoogStatement(node, 'provide');
+};
+
+exports.isRequireExpression = function(node) {
+  return isGoogCallExpression(node, 'require');
+};
+
+exports.isRequireStatement = function(node) {
+  return isGoogStatement(node, 'require');
+};