ast-walkers: hide iterator in searchOpts

Now that searchOpts have one required property, we may remove all
`opts = opts || {}` checking.

Author: eush77

lib/ast-walkers.js

@@ -5,57 +5,59 @@ var TypeIndex = require('./type-index');
 var walkers = exports;
 
 
-walkers.topScan = function (node, nodeIndex, parent, iterator, opts) {
+walkers.topScan = function (node, nodeIndex, parent, opts) {
   if (parent) {
     // We would like to avoid spinning an extra loop through the starting
     // node's siblings just to count its typeIndex.
     throw Error('topScan is supposed to be called from the root node');
   }
 
-  iterator(node, nodeIndex, parent);
+  if (!opts.typeIndex) {
+    opts.iterator(node, nodeIndex, parent);
+  }
   walkers.descendant.apply(this, arguments);
 };
 
 
-walkers.descendant = function (node, nodeIndex, parent, iterator, opts) {
+walkers.descendant = function (node, nodeIndex, parent, opts) {
   if (!node.children || !node.children.length) {
     return;
   }
 
-  if ((opts = opts || {}).typeIndex) {
+  if (opts.typeIndex) {
     var typeIndex = TypeIndex();
   }
 
   node.children.forEach(function (child, childIndex) {
-    iterator(child, childIndex, node,
-             opts.typeIndex ? { typeIndex: typeIndex(child) } : undefined);
-    walkers.descendant(child, childIndex, node, iterator, opts);
+    opts.iterator(child, childIndex, node,
+                  opts.typeIndex ? { typeIndex: typeIndex(child) } : undefined);
+    walkers.descendant(child, childIndex, node, opts);
   });
 };
 
 
-walkers.child = function (node, nodeIndex, parent, iterator, opts) {
+walkers.child = function (node, nodeIndex, parent, opts) {
   if (!node.children || !node.children.length) {
     return;
   }
 
-  if ((opts = opts || {}).typeIndex) {
+  if (opts.typeIndex) {
     var typeIndex = TypeIndex();
   }
 
   node.children.forEach(function (child, childIndex) {
-    iterator(child, childIndex, node,
-             opts.typeIndex ? { typeIndex: typeIndex(child) } : undefined);
+    opts.iterator(child, childIndex, node,
+                  opts.typeIndex ? { typeIndex: typeIndex(child) } : undefined);
   });
 };
 
 
-walkers.adjacentSibling = function (node, nodeIndex, parent, iterator, opts) {
+walkers.adjacentSibling = function (node, nodeIndex, parent, opts) {
   if (!parent) {
     return;
   }
 
-  if ((opts = opts || {}).typeIndex) {
+  if (opts.typeIndex) {
     var typeIndex = TypeIndex();
 
     // Prefill type indexes with preceding nodes.
@@ -66,18 +68,18 @@ walkers.adjacentSibling = function (node, nodeIndex, parent, iterator, opts) {
 
   if (++nodeIndex < parent.children.length) {
     node = parent.children[nodeIndex];
-    iterator(node, nodeIndex, parent,
-             opts.typeIndex ? { typeIndex: typeIndex(node) } : undefined);
+    opts.iterator(node, nodeIndex, parent,
+                  opts.typeIndex ? { typeIndex: typeIndex(node) } : undefined);
   }
 };
 
 
-walkers.generalSibling = function (node, nodeIndex, parent, iterator, opts) {
+walkers.generalSibling = function (node, nodeIndex, parent, opts) {
   if (!parent) {
     return;
   }
 
-  if ((opts = opts || {}).typeIndex) {
+  if (opts.typeIndex) {
     var typeIndex = TypeIndex();
 
     // Prefill type indexes with preceding nodes.
@@ -88,7 +90,7 @@ walkers.generalSibling = function (node, nodeIndex, parent, iterator, opts) {
 
   while (++nodeIndex < parent.children.length) {
     node = parent.children[nodeIndex];
-    iterator(node, nodeIndex, parent,
-             opts.typeIndex ? { typeIndex: typeIndex(node) } : undefined);
+    opts.iterator(node, nodeIndex, parent,
+                  opts.typeIndex ? { typeIndex: typeIndex(node) } : undefined);
   }
 };

lib/select.js

@@ -36,12 +36,15 @@ select.rule = function (rule, ast) {
       '+': walkers.adjacentSibling,
       '~': walkers.generalSibling
     })[rule.nestingOperator](
-      node, nodeIndex, parent, match.bind(null, rule), searchOpts(rule)
+      node,
+      nodeIndex,
+      parent,
+      searchOpts({ iterator: match.bind(null, rule) }, rule)
     );
   }
 
   function match (rule, node, nodeIndex, parent, props) {
-    if (matchNode(rule, node, nodeIndex, parent, props)) {
+    if (matchNode.apply(this, arguments)) {
       if (rule.rule) {
         search(rule.rule, node, nodeIndex, parent);
       }
@@ -53,15 +56,15 @@ select.rule = function (rule, ast) {
 };
 
 
-function searchOpts (rule) {
-  var needsTypeIndex = rule.pseudos && rule.pseudos.some(function (pseudo) {
-    return pseudo.name == 'nth-of-type' ||
-      pseudo.name == 'nth-last-of-type' ||
-      pseudo.name == 'first-of-type' ||
-      pseudo.name == 'last-of-type';
-  });
-
-  if (needsTypeIndex) {
-    return { typeIndex: true };
+function searchOpts (opts, rule) {
+  if (rule.pseudos && rule.pseudos.some(function (pseudo) {
+    return (pseudo.name == 'nth-of-type' ||
+            pseudo.name == 'nth-last-of-type' ||
+            pseudo.name == 'first-of-type' ||
+            pseudo.name == 'last-of-type');
+  })) {
+    opts.typeIndex = true;
   }
+
+  return opts;
 }