Merge pull request #17 from jsbin/refactor/babel-transform

Refactor/babel transform

.gitignore

@@ -1,2 +1,3 @@
 .DS_Store
 node_modules
+tmp

.travis.yml

@@ -2,8 +2,5 @@ sudo: false
 language: node_js
 notifications:
   email: false
-before_script:
-- npm install
 node_js:
-- "0.10"
-- 4
+- 8

lib/index.js

@@ -0,0 +1,49 @@
+const generateBefore = (t, id) =>
+  t.variableDeclaration('var', [
+    t.variableDeclarator(
+      id,
+      t.callExpression(
+        t.memberExpression(t.identifier('Date'), t.identifier('now')),
+        []
+      )
+    ),
+  ]);
+
+const generateInside = (t, id, line, timeout) =>
+  t.ifStatement(
+    t.binaryExpression(
+      '>',
+      t.binaryExpression(
+        '-',
+        t.callExpression(
+          t.memberExpression(t.identifier('Date'), t.identifier('now')),
+          []
+        ),
+        id
+      ),
+      t.numericLiteral(timeout)
+    ),
+    t.breakStatement()
+  );
+
+const protect = (t, timeout) => path => {
+  const id = path.scope.generateUidIdentifier('LP');
+  const before = generateBefore(t, id);
+  const inside = generateInside(t, id, path.node.loc.start.line, timeout);
+  const body = path.get('body');
+
+  // if we have an expression statement, convert it to a block
+  if (t.isExpressionStatement(body)) {
+    body.replaceWith(t.blockStatement([body.node]));
+  }
+  path.insertBefore(before);
+  body.unshiftContainer('body', inside);
+};
+
+module.exports = (timeout = 100) => ({ types: t }) => ({
+  visitor: {
+    WhileStatement: protect(t, timeout),
+    ForStatement: protect(t, timeout),
+    DoWhileStatement: protect(t, timeout),
+  },
+});