feat(h2x-core): add state support

Author: gregberge

packages/h2x-core/src/index.js

@@ -3,7 +3,6 @@ import parse from 'h2x-parse'
 import generate from 'h2x-generate'
 import traverse from 'h2x-traverse'
 
-
 const reduceVisitors = (visitors, opts) => {
   Object.keys(visitors).forEach(key => {
     const visitor = visitors[key]
@@ -31,9 +30,9 @@ const mergePlugins = plugins =>
 
 export { traverse, generate }
 
-export function transform(code, { plugins = [] } = {}) {
+export function transform(code, { plugins = [], state = {} } = {}) {
   const ast = parse(code)
   const { visitor, generator } = mergePlugins(plugins)
-  traverse(ast, visitor)
+  traverse(ast, visitor, state)
   return generate(ast, generator)
 }

packages/h2x-core/src/index.test.js

@@ -31,4 +31,37 @@ describe('transform', () => {
     const result = transform(code, { plugins: [simpleJsx] })
     expect(result).toBe(`<div />\n`)
   })
+
+  it('should support state', () => {
+    class JSXNode {
+      static [NODE_TYPE] = 'JSXElement'
+
+      constructor(name) {
+        this.name = name
+      }
+    }
+
+    const simpleJsx = () => ({
+      visitor: {
+        HTMLElement: {
+          enter(path, state) {
+            state.tags.push(path.node.tagName)
+            path.replace(new JSXNode('div'))
+          },
+        },
+      },
+      generator: {
+        JSXElement: {
+          enter(path, generator) {
+            generator.writeLine(`<${path.node.name} />`)
+          },
+        },
+      },
+    })
+    const state = { tags: [] }
+    const code = `<div></div>`
+    const result = transform(code, { plugins: [simpleJsx], state })
+    expect(result).toBe(`<div />\n`)
+    expect(state.tags).toEqual(['DIV'])
+  })
 })