feat: stream rendering, closed #361 fixes #360

test/unit/render/render.ts

@@ -3,8 +3,10 @@ import { Context } from '../../../src/context/context'
 import { HTMLToken } from '../../../src/tokens/html-token'
 import { Render } from '../../../src/render/render'
 import { HTML } from '../../../src/template/html'
-import { Emitter } from '../../../src/render/emitter'
+import { SimpleEmitter } from '../../../src/emitters/simple-emitter'
 import { toThenable } from '../../../src/util/async'
+import { Tag } from '../../../src/template/tag/tag'
+import { TagToken } from '../../../src/types'
 
 describe('render', function () {
   let render: Render
@@ -16,8 +18,52 @@ describe('render', function () {
     it('should render html', async function () {
       const scope = new Context()
       const token = { getContent: () => '<p>' } as HTMLToken
-      const html = await toThenable(render.renderTemplates([new HTML(token)], scope, new Emitter(scope.opts.keepOutputType)))
+      const html = await toThenable(render.renderTemplates([new HTML(token)], scope, new SimpleEmitter()))
       return expect(html).to.equal('<p>')
     })
   })
+
+  describe('.renderTemplatesToNodeStream()', function () {
+    it('should render to html stream', function (done) {
+      const scope = new Context()
+      const tpls = [
+        new HTML({ getContent: () => '<p>' } as HTMLToken),
+        new HTML({ getContent: () => '</p>' } as HTMLToken)
+      ]
+      const stream = render.renderTemplatesToNodeStream(tpls, scope)
+      let result = ''
+      stream.on('data', (data) => {
+        result += data
+      })
+      stream.on('end', () => {
+        expect(result).to.equal('<p></p>')
+        done()
+      })
+    })
+    it('should render to html stream asyncly', function (done) {
+      const scope = new Context()
+      const tpls = [
+        new HTML({ getContent: () => '<p>' } as HTMLToken),
+        new Tag({ content: 'foo', args: '', name: 'foo' } as TagToken, [], {
+          tags: {
+            get: () => ({
+              render: () => new Promise(
+                resolve => setTimeout(() => resolve('async tag'), 10)
+              )
+            })
+          }
+        } as any),
+        new HTML({ getContent: () => '</p>' } as HTMLToken)
+      ]
+      const stream = render.renderTemplatesToNodeStream(tpls, scope)
+      let result = ''
+      stream.on('data', (data) => {
+        result += data
+      })
+      stream.on('end', () => {
+        expect(result).to.equal('<p>async tag</p>')
+        done()
+      })
+    })
+  })
 })