Add simplification of nodes

1 files changed, 44 insertions, 0 deletions

diff --git a/lib/html/simplify.js b/lib/html/simplify.js
new file mode 100644
index 0000000..52a1b0a
--- /dev/null
+++ b/lib/html/simplify.js
@@ -0,0 +1,44 @@
+var _ = require("underscore");
+
+var ast = require("./ast");
+
+function simplify(node) {
+    return simplifiers[node.type](node);
+};
+
+var simplifiers = {
+    fragment: simplifyFragment,
+    element: simplifyElement,
+    text: simplifyText
+};
+
+function simplifyFragment(node) {
+    return ast.fragment(simplifyNodes(node.children));
+}
+
+function simplifyElement(node) {
+    return ast.elementWithTag(node.tag, simplifyNodes(node.children));
+}
+
+function simplifyText(node) {
+    return node;
+}
+
+function simplifyNodes(nodes) {
+    var children = [];
+    
+    nodes.map(simplify).forEach(function(child) {
+        var lastChild = children[children.length - 1];
+        if (child.type === "element" && !child.tag.fresh && lastChild && _.isEqual(lastChild.tag, child.tag)) {
+            child.children.forEach(function(grandChild) {
+                // Mutation is fine since simplifying elements create a copy of the children.
+                lastChild.children.push(grandChild);
+            });
+        } else {
+            children.push(child);
+        }
+    });
+    return children;
+}
+
+module.exports = simplify;