add a top level analyze method for path marking sugar

packages/babel-core/src/api/node.js

@@ -32,6 +32,7 @@ import Pipeline from "../transformation/pipeline";
 export { Pipeline };
 
 let pipeline = new Pipeline;
+export let analyse = pipeline.analyse.bind(pipeline);
 export let transform = pipeline.transform.bind(pipeline);
 export let transformFromAst = pipeline.transformFromAst.bind(pipeline);
 

packages/babel-core/src/transformation/pipeline.js

@@ -1,6 +1,7 @@
 /* @noflow */
 
 import normalizeAst from "../helpers/normalize-ast";
+import Plugin from "./plugin";
 import File from "./file";
 
 export default class Pipeline {
@@ -28,6 +29,15 @@ export default class Pipeline {
     });
   }
 
+  analyse(code: string, opts: Object = {}, visitor?) {
+    opts.code = false;
+    if (visitor) {
+      opts.plugins = opts.plugins || [];
+      opts.plugins.push(new Plugin({ visitor }));
+    }
+    return this.transform(code, opts).metadata;
+  }
+
   transformFromAst(ast, code: string, opts: Object) {
     ast = normalizeAst(ast);
 

packages/babel-core/test/api.js

@@ -24,6 +24,26 @@ function transformAsync(code, opts) {
 }
 
 suite("api", function () {
+  test("analyze", function () {
+    assert.equal(babel.analyse("foobar;").marked.length, 0);
+
+    assert.equal(babel.analyse("foobar;", {
+      plugins: [new Plugin({
+        visitor: {
+          Program: function (path) {
+            path.mark("category", "foobar");
+          }
+        }
+      })]
+    }).marked[0].message, "foobar");
+
+    assert.equal(babel.analyse("foobar;", {}, {
+      Program: function (path) {
+        path.mark("category", "foobar");
+      }
+    }).marked[0].message, "foobar");
+  });
+
   test("transformFile", function (done) {
     babel.transformFile(__dirname + "/fixtures/api/file.js", {}, function (err, res) {
       if (err) return done(err);