From 5a3732296f8ca1c6c46fc9f8f3de54f67221fa2d Mon Sep 17 00:00:00 2001
From: Brandon Smith <brandon93s@gmail.com>
Date: Mon, 29 Jan 2018 02:19:53 -0500
Subject: [PATCH] Inject HTML tag if missing (#654)

* Inject HTML tag if missing

* Update sibling bundle node insert logic
---
 src/packagers/HTMLPackager.js                 | 51 ++++++++++++++-----
 test/html.js                                  | 42 ++++++++++++++-
 .../html-css-optional-elements/index.css      |  3 ++
 .../html-css-optional-elements/index.html     |  3 ++
 .../html-css-optional-elements/index.js       |  2 +
 .../html-css-optional-elements/other.js       |  1 +
 6 files changed, 87 insertions(+), 15 deletions(-)
 create mode 100644 test/integration/html-css-optional-elements/index.css
 create mode 100644 test/integration/html-css-optional-elements/index.html
 create mode 100644 test/integration/html-css-optional-elements/index.js
 create mode 100644 test/integration/html-css-optional-elements/other.js

diff --git a/src/packagers/HTMLPackager.js b/src/packagers/HTMLPackager.js
index 2a6fb069adc..511385d02a3 100644
--- a/src/packagers/HTMLPackager.js
+++ b/src/packagers/HTMLPackager.js
@@ -3,6 +3,18 @@ const posthtml = require('posthtml');
 const path = require('path');
 const urlJoin = require('../utils/urlJoin');
 
+// https://www.w3.org/TR/html5/dom.html#metadata-content-2
+const metadataContent = new Set([
+  'base',
+  'link',
+  'meta',
+  'noscript',
+  'script',
+  'style',
+  'template',
+  'title'
+]);
+
 class HTMLPackager extends Packager {
   async addAsset(asset) {
     let html = asset.generated.html || '';
@@ -22,27 +34,27 @@ class HTMLPackager extends Packager {
     await this.dest.write(html);
   }
 
-  getHeadContent(tree) {
-    let head = find(tree, 'head');
-    if (!head) {
-      let html = find(tree, 'html');
-      head = {tag: 'head'};
-      html.content.unshift(head);
+  addBundlesToTree(bundles, tree) {
+    const head = find(tree, 'head');
+    if (head) {
+      const content = head.content || (head.content = []);
+      content.push(...bundles);
+      return;
     }
 
-    if (!head.content) {
-      head.content = [];
-    }
+    const html = find(tree, 'html');
+    const content = html ? html.content || (html.content = []) : tree;
+    const index = findBundleInsertIndex(content);
 
-    return head;
+    content.splice(index, 0, ...bundles);
   }
 
   insertSiblingBundles(siblingBundles, tree) {
-    let head = this.getHeadContent(tree);
+    const bundles = [];
 
     for (let bundle of siblingBundles) {
       if (bundle.type === 'css') {
-        head.content.push({
+        bundles.push({
           tag: 'link',
           attrs: {
             rel: 'stylesheet',
@@ -50,7 +62,7 @@ class HTMLPackager extends Packager {
           }
         });
       } else if (bundle.type === 'js') {
-        head.content.push({
+        bundles.push({
           tag: 'script',
           attrs: {
             src: urlJoin(this.options.publicURL, path.basename(bundle.name))
@@ -58,6 +70,8 @@ class HTMLPackager extends Packager {
         });
       }
     }
+
+    this.addBundlesToTree(bundles, tree);
   }
 }
 
@@ -71,4 +85,15 @@ function find(tree, tag) {
   return res;
 }
 
+function findBundleInsertIndex(content) {
+  for (let index = 0; index < content.length; index++) {
+    const node = content[index];
+    if (node && node.tag && !metadataContent.has(node.tag)) {
+      return index;
+    }
+  }
+
+  return 0;
+}
+
 module.exports = HTMLPackager;
diff --git a/test/html.js b/test/html.js
index af313a1e94c..eec972ad4a2 100644
--- a/test/html.js
+++ b/test/html.js
@@ -143,7 +143,7 @@ describe('html', function() {
     );
   });
 
-  it('should insert a HEAD element if needed when adding CSS bundles', async function() {
+  it('should insert sibling bundles before body element if no HEAD', async function() {
     let b = await bundle(__dirname + '/integration/html-css-head/index.html');
 
     assertBundleTree(b, {
@@ -169,7 +169,7 @@ describe('html', function() {
 
     let html = fs.readFileSync(__dirname + '/dist/index.html');
     assert(
-      /<head><link rel="stylesheet" href="[/\\]{1}dist[/\\]{1}[a-f0-9]+\.css"><\/head>/.test(
+      /<html>\s*<link rel="stylesheet" href="[/\\]{1}dist[/\\]{1}[a-f0-9]+\.css">\s*<body>/.test(
         html
       )
     );
@@ -210,6 +210,44 @@ describe('html', function() {
     assert(/<script src="[/\\]{1}dist[/\\]{1}[a-f0-9]+\.js">/.test(html));
   });
 
+  it('should insert sibling bundles at correct location in tree when optional elements are absent', async function() {
+    let b = await bundle(
+      __dirname + '/integration/html-css-optional-elements/index.html'
+    );
+
+    assertBundleTree(b, {
+      name: 'index.html',
+      assets: ['index.html'],
+      childBundles: [
+        {
+          type: 'js',
+          assets: ['index.js', 'index.css'],
+          childBundles: [
+            {
+              type: 'css',
+              assets: ['index.css'],
+              childBundles: []
+            },
+            {
+              type: 'map'
+            }
+          ]
+        },
+        {
+          type: 'js',
+          assets: ['other.js']
+        }
+      ]
+    });
+
+    let html = fs.readFileSync(__dirname + '/dist/index.html');
+    assert(
+      /<\/script>\s*<link rel="stylesheet" href="[/\\]{1}dist[/\\]{1}[a-f0-9]+\.css"><h1>Hello/.test(
+        html
+      )
+    );
+  });
+
   it('should minify HTML in production mode', async function() {
     await bundle(__dirname + '/integration/htmlnano/index.html', {
       production: true
diff --git a/test/integration/html-css-optional-elements/index.css b/test/integration/html-css-optional-elements/index.css
new file mode 100644
index 00000000000..67ce83e4d09
--- /dev/null
+++ b/test/integration/html-css-optional-elements/index.css
@@ -0,0 +1,3 @@
+body {
+  background: red;
+}
diff --git a/test/integration/html-css-optional-elements/index.html b/test/integration/html-css-optional-elements/index.html
new file mode 100644
index 00000000000..5872bd0c236
--- /dev/null
+++ b/test/integration/html-css-optional-elements/index.html
@@ -0,0 +1,3 @@
+<script src="other.js"></script>
+<h1>Hello world</h1>
+<script src="index.js"></script>
diff --git a/test/integration/html-css-optional-elements/index.js b/test/integration/html-css-optional-elements/index.js
new file mode 100644
index 00000000000..8a604206cf5
--- /dev/null
+++ b/test/integration/html-css-optional-elements/index.js
@@ -0,0 +1,2 @@
+require('./index.css');
+alert('Hi');
diff --git a/test/integration/html-css-optional-elements/other.js b/test/integration/html-css-optional-elements/other.js
new file mode 100644
index 00000000000..69aa795cedd
--- /dev/null
+++ b/test/integration/html-css-optional-elements/other.js
@@ -0,0 +1 @@
+alert('Other');