From 4c258caba245fbd311b0e8f157a9d8a5fc1c54b7 Mon Sep 17 00:00:00 2001
From: Petrik <petrik@deheus.net>
Date: Sat, 11 Jul 2020 12:23:37 +0200
Subject: [PATCH] Add copy button for copying guide code examples [skip ci]

Instead of carefully selecting the code in examples, use a copy button
for copying the code. This uses https://clipboardjs.com/ for copying.

For the bash code examples only line starting with $ prompt are copied.
The $ prompt itself is not copied.
---
 guides/assets/javascripts/clipboard.js   |  7 +++++++
 guides/assets/javascripts/guides.js      | 11 +++++++++++
 guides/assets/stylesheets/main.css       | 21 +++++++++++++++++++++
 guides/assets/stylesheets/main.rtl.css   | 21 +++++++++++++++++++++
 guides/rails_guides/markdown/renderer.rb | 24 +++++++++++++++++++-----
 guides/source/layout.html.erb            |  1 +
 6 files changed, 80 insertions(+), 5 deletions(-)
 create mode 100644 guides/assets/javascripts/clipboard.js

diff --git a/guides/assets/javascripts/clipboard.js b/guides/assets/javascripts/clipboard.js
new file mode 100644
index 00000000000..b9ed143b3e1
--- /dev/null
+++ b/guides/assets/javascripts/clipboard.js
@@ -0,0 +1,7 @@
+/*!
+ * clipboard.js v2.0.6
+ * https://clipboardjs.com/
+ *
+ * Licensed MIT © Zeno Rocha
+ */
+!function(t,e){"object"==typeof exports&&"object"==typeof module?module.exports=e():"function"==typeof define&&define.amd?define([],e):"object"==typeof exports?exports.ClipboardJS=e():t.ClipboardJS=e()}(this,function(){return o={},r.m=n=[function(t,e){t.exports=function(t){var e;if("SELECT"===t.nodeName)t.focus(),e=t.value;else if("INPUT"===t.nodeName||"TEXTAREA"===t.nodeName){var n=t.hasAttribute("readonly");n||t.setAttribute("readonly",""),t.select(),t.setSelectionRange(0,t.value.length),n||t.removeAttribute("readonly"),e=t.value}else{t.hasAttribute("contenteditable")&&t.focus();var o=window.getSelection(),r=document.createRange();r.selectNodeContents(t),o.removeAllRanges(),o.addRange(r),e=o.toString()}return e}},function(t,e){function n(){}n.prototype={on:function(t,e,n){var o=this.e||(this.e={});return(o[t]||(o[t]=[])).push({fn:e,ctx:n}),this},once:function(t,e,n){var o=this;function r(){o.off(t,r),e.apply(n,arguments)}return r._=e,this.on(t,r,n)},emit:function(t){for(var e=[].slice.call(arguments,1),n=((this.e||(this.e={}))[t]||[]).slice(),o=0,r=n.length;o<r;o++)n[o].fn.apply(n[o].ctx,e);return this},off:function(t,e){var n=this.e||(this.e={}),o=n[t],r=[];if(o&&e)for(var i=0,a=o.length;i<a;i++)o[i].fn!==e&&o[i].fn._!==e&&r.push(o[i]);return r.length?n[t]=r:delete n[t],this}},t.exports=n,t.exports.TinyEmitter=n},function(t,e,n){var d=n(3),h=n(4);t.exports=function(t,e,n){if(!t&&!e&&!n)throw new Error("Missing required arguments");if(!d.string(e))throw new TypeError("Second argument must be a String");if(!d.fn(n))throw new TypeError("Third argument must be a Function");if(d.node(t))return s=e,f=n,(u=t).addEventListener(s,f),{destroy:function(){u.removeEventListener(s,f)}};if(d.nodeList(t))return a=t,c=e,l=n,Array.prototype.forEach.call(a,function(t){t.addEventListener(c,l)}),{destroy:function(){Array.prototype.forEach.call(a,function(t){t.removeEventListener(c,l)})}};if(d.string(t))return o=t,r=e,i=n,h(document.body,o,r,i);throw new TypeError("First argument must be a String, HTMLElement, HTMLCollection, or NodeList");var o,r,i,a,c,l,u,s,f}},function(t,n){n.node=function(t){return void 0!==t&&t instanceof HTMLElement&&1===t.nodeType},n.nodeList=function(t){var e=Object.prototype.toString.call(t);return void 0!==t&&("[object NodeList]"===e||"[object HTMLCollection]"===e)&&"length"in t&&(0===t.length||n.node(t[0]))},n.string=function(t){return"string"==typeof t||t instanceof String},n.fn=function(t){return"[object Function]"===Object.prototype.toString.call(t)}},function(t,e,n){var a=n(5);function i(t,e,n,o,r){var i=function(e,n,t,o){return function(t){t.delegateTarget=a(t.target,n),t.delegateTarget&&o.call(e,t)}}.apply(this,arguments);return t.addEventListener(n,i,r),{destroy:function(){t.removeEventListener(n,i,r)}}}t.exports=function(t,e,n,o,r){return"function"==typeof t.addEventListener?i.apply(null,arguments):"function"==typeof n?i.bind(null,document).apply(null,arguments):("string"==typeof t&&(t=document.querySelectorAll(t)),Array.prototype.map.call(t,function(t){return i(t,e,n,o,r)}))}},function(t,e){if("undefined"!=typeof Element&&!Element.prototype.matches){var n=Element.prototype;n.matches=n.matchesSelector||n.mozMatchesSelector||n.msMatchesSelector||n.oMatchesSelector||n.webkitMatchesSelector}t.exports=function(t,e){for(;t&&9!==t.nodeType;){if("function"==typeof t.matches&&t.matches(e))return t;t=t.parentNode}}},function(t,e,n){"use strict";n.r(e);var o=n(0),r=n.n(o),i="function"==typeof Symbol&&"symbol"==typeof Symbol.iterator?function(t){return typeof t}:function(t){return t&&"function"==typeof Symbol&&t.constructor===Symbol&&t!==Symbol.prototype?"symbol":typeof t};function a(t,e){for(var n=0;n<e.length;n++){var o=e[n];o.enumerable=o.enumerable||!1,o.configurable=!0,"value"in o&&(o.writable=!0),Object.defineProperty(t,o.key,o)}}function c(t){!function(t,e){if(!(t instanceof e))throw new TypeError("Cannot call a class as a function")}(this,c),this.resolveOptions(t),this.initSelection()}var l=(function(t,e,n){return e&&a(t.prototype,e),n&&a(t,n),t}(c,[{key:"resolveOptions",value:function(t){var e=0<arguments.length&&void 0!==t?t:{};this.action=e.action,this.container=e.container,this.emitter=e.emitter,this.target=e.target,this.text=e.text,this.trigger=e.trigger,this.selectedText=""}},{key:"initSelection",value:function(){this.text?this.selectFake():this.target&&this.selectTarget()}},{key:"selectFake",value:function(){var t=this,e="rtl"==document.documentElement.getAttribute("dir");this.removeFake(),this.fakeHandlerCallback=function(){return t.removeFake()},this.fakeHandler=this.container.addEventListener("click",this.fakeHandlerCallback)||!0,this.fakeElem=document.createElement("textarea"),this.fakeElem.style.fontSize="12pt",this.fakeElem.style.border="0",this.fakeElem.style.padding="0",this.fakeElem.style.margin="0",this.fakeElem.style.position="absolute",this.fakeElem.style[e?"right":"left"]="-9999px";var n=window.pageYOffset||document.documentElement.scrollTop;this.fakeElem.style.top=n+"px",this.fakeElem.setAttribute("readonly",""),this.fakeElem.value=this.text,this.container.appendChild(this.fakeElem),this.selectedText=r()(this.fakeElem),this.copyText()}},{key:"removeFake",value:function(){this.fakeHandler&&(this.container.removeEventListener("click",this.fakeHandlerCallback),this.fakeHandler=null,this.fakeHandlerCallback=null),this.fakeElem&&(this.container.removeChild(this.fakeElem),this.fakeElem=null)}},{key:"selectTarget",value:function(){this.selectedText=r()(this.target),this.copyText()}},{key:"copyText",value:function(){var e=void 0;try{e=document.execCommand(this.action)}catch(t){e=!1}this.handleResult(e)}},{key:"handleResult",value:function(t){this.emitter.emit(t?"success":"error",{action:this.action,text:this.selectedText,trigger:this.trigger,clearSelection:this.clearSelection.bind(this)})}},{key:"clearSelection",value:function(){this.trigger&&this.trigger.focus(),document.activeElement.blur(),window.getSelection().removeAllRanges()}},{key:"destroy",value:function(){this.removeFake()}},{key:"action",set:function(t){var e=0<arguments.length&&void 0!==t?t:"copy";if(this._action=e,"copy"!==this._action&&"cut"!==this._action)throw new Error('Invalid "action" value, use either "copy" or "cut"')},get:function(){return this._action}},{key:"target",set:function(t){if(void 0!==t){if(!t||"object"!==(void 0===t?"undefined":i(t))||1!==t.nodeType)throw new Error('Invalid "target" value, use a valid Element');if("copy"===this.action&&t.hasAttribute("disabled"))throw new Error('Invalid "target" attribute. Please use "readonly" instead of "disabled" attribute');if("cut"===this.action&&(t.hasAttribute("readonly")||t.hasAttribute("disabled")))throw new Error('Invalid "target" attribute. You can\'t cut text from elements with "readonly" or "disabled" attributes');this._target=t}},get:function(){return this._target}}]),c),u=n(1),s=n.n(u),f=n(2),d=n.n(f),h="function"==typeof Symbol&&"symbol"==typeof Symbol.iterator?function(t){return typeof t}:function(t){return t&&"function"==typeof Symbol&&t.constructor===Symbol&&t!==Symbol.prototype?"symbol":typeof t},p=function(t,e,n){return e&&y(t.prototype,e),n&&y(t,n),t};function y(t,e){for(var n=0;n<e.length;n++){var o=e[n];o.enumerable=o.enumerable||!1,o.configurable=!0,"value"in o&&(o.writable=!0),Object.defineProperty(t,o.key,o)}}var m=(function(t,e){if("function"!=typeof e&&null!==e)throw new TypeError("Super expression must either be null or a function, not "+typeof e);t.prototype=Object.create(e&&e.prototype,{constructor:{value:t,enumerable:!1,writable:!0,configurable:!0}}),e&&(Object.setPrototypeOf?Object.setPrototypeOf(t,e):t.__proto__=e)}(v,s.a),p(v,[{key:"resolveOptions",value:function(t){var e=0<arguments.length&&void 0!==t?t:{};this.action="function"==typeof e.action?e.action:this.defaultAction,this.target="function"==typeof e.target?e.target:this.defaultTarget,this.text="function"==typeof e.text?e.text:this.defaultText,this.container="object"===h(e.container)?e.container:document.body}},{key:"listenClick",value:function(t){var e=this;this.listener=d()(t,"click",function(t){return e.onClick(t)})}},{key:"onClick",value:function(t){var e=t.delegateTarget||t.currentTarget;this.clipboardAction&&(this.clipboardAction=null),this.clipboardAction=new l({action:this.action(e),target:this.target(e),text:this.text(e),container:this.container,trigger:e,emitter:this})}},{key:"defaultAction",value:function(t){return b("action",t)}},{key:"defaultTarget",value:function(t){var e=b("target",t);if(e)return document.querySelector(e)}},{key:"defaultText",value:function(t){return b("text",t)}},{key:"destroy",value:function(){this.listener.destroy(),this.clipboardAction&&(this.clipboardAction.destroy(),this.clipboardAction=null)}}],[{key:"isSupported",value:function(t){var e=0<arguments.length&&void 0!==t?t:["copy","cut"],n="string"==typeof e?[e]:e,o=!!document.queryCommandSupported;return n.forEach(function(t){o=o&&!!document.queryCommandSupported(t)}),o}}]),v);function v(t,e){!function(t,e){if(!(t instanceof e))throw new TypeError("Cannot call a class as a function")}(this,v);var n=function(t,e){if(!t)throw new ReferenceError("this hasn't been initialised - super() hasn't been called");return!e||"object"!=typeof e&&"function"!=typeof e?t:e}(this,(v.__proto__||Object.getPrototypeOf(v)).call(this));return n.resolveOptions(e),n.listenClick(t),n}function b(t,e){var n="data-clipboard-"+t;if(e.hasAttribute(n))return e.getAttribute(n)}e.default=m}],r.c=o,r.d=function(t,e,n){r.o(t,e)||Object.defineProperty(t,e,{enumerable:!0,get:n})},r.r=function(t){"undefined"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(t,Symbol.toStringTag,{value:"Module"}),Object.defineProperty(t,"__esModule",{value:!0})},r.t=function(e,t){if(1&t&&(e=r(e)),8&t)return e;if(4&t&&"object"==typeof e&&e&&e.__esModule)return e;var n=Object.create(null);if(r.r(n),Object.defineProperty(n,"default",{enumerable:!0,value:e}),2&t&&"string"!=typeof e)for(var o in e)r.d(n,o,function(t){return e[t]}.bind(null,o));return n},r.n=function(t){var e=t&&t.__esModule?function(){return t.default}:function(){return t};return r.d(e,"a",e),e},r.o=function(t,e){return Object.prototype.hasOwnProperty.call(t,e)},r.p="",r(r.s=6).default;function r(t){if(o[t])return o[t].exports;var e=o[t]={i:t,l:!1,exports:{}};return n[t].call(e.exports,e,e.exports,r),e.l=!0,e.exports}var n,o});
diff --git a/guides/assets/javascripts/guides.js b/guides/assets/javascripts/guides.js
index 87097c50c36..8191998485f 100644
--- a/guides/assets/javascripts/guides.js
+++ b/guides/assets/javascripts/guides.js
@@ -67,5 +67,16 @@
         unwrap(moreInfoLinks);
       }
     });
+
+    var clipboard = new ClipboardJS('.clipboard-button');
+    clipboard.on('success', function(e) {
+      var trigger = e.trigger;
+      var triggerLabel = trigger.innerHTML;
+      trigger.innerHTML = 'Copied!';
+      setTimeout(function(){
+        trigger.innerHTML = triggerLabel;
+      }, 3000);
+      e.clearSelection();
+    });
   });
 }).call(this);
diff --git a/guides/assets/stylesheets/main.css b/guides/assets/stylesheets/main.css
index 803049b75d0..aeb3dfcce8f 100644
--- a/guides/assets/stylesheets/main.css
+++ b/guides/assets/stylesheets/main.css
@@ -238,6 +238,26 @@ body {
   }
 }
 
+.clipboard-button {
+  background: #dbdbdb;
+  border: 0;
+  border-radius: 5px;
+  padding: 2px 10px;
+  position: absolute;
+  bottom: 2px;
+  right: 2px
+}
+
+.clipboard-button:active {
+  background: #ccc;
+}
+
+.clipboard-content {
+  opacity:0;
+  position:absolute;
+  z-index:-1;
+}
+
 #header {
   background: #c52f24 url(../images/header_tile.gif) repeat-x;
   color: #FFF;
@@ -670,6 +690,7 @@ only screen and (                min-resolution: 2dppx) {
 div.code_container {
   background: #EEE url(../images/tab_grey.gif) no-repeat left top;
   padding: 0.25em 1em 0.5em 48px;
+  position: relative;
 }
 
 .note {
diff --git a/guides/assets/stylesheets/main.rtl.css b/guides/assets/stylesheets/main.rtl.css
index 561f06d8398..4ec600e0b55 100644
--- a/guides/assets/stylesheets/main.rtl.css
+++ b/guides/assets/stylesheets/main.rtl.css
@@ -239,6 +239,26 @@ body {
   }
 }
 
+.clipboard-button {
+  background: #dbdbdb;
+  border: 0;
+  border-radius: 5px;
+  padding: 2px 10px;
+  position: absolute;
+  bottom: 2px;
+  right: 2px
+}
+
+.clipboard-button:active {
+  background: #ccc;
+}
+
+.clipboard-content {
+  opacity:0;
+  position:absolute;
+  z-index:-1;
+}
+
 #header {
   background: #c52f24 url(../images/header_tile.gif) repeat-x;
   color: #FFF;
@@ -671,6 +691,7 @@ only screen and (                min-resolution: 2dppx) {
 div.code_container {
   background: #EEE url(../images/tab_grey.gif) no-repeat right top;
   padding: 0.25em 48px 0.5em 1em;
+  position: relative;
 }
 
 .note {
diff --git a/guides/rails_guides/markdown/renderer.rb b/guides/rails_guides/markdown/renderer.rb
index 2600897c9a7..8e560da515f 100644
--- a/guides/rails_guides/markdown/renderer.rb
+++ b/guides/rails_guides/markdown/renderer.rb
@@ -13,11 +13,14 @@ module RailsGuides
       def block_code(code, language)
         formatter = Rouge::Formatters::HTML.new
         lexer = ::Rouge::Lexer.find_fancy(lexer_language(language))
-        code = formatter.format(lexer.lex(code))
-        <<-HTML
-<div class="code_container">
-<pre><code class="highlight #{lexer_language(language)}">#{code}</code></pre>
-</div>
+        formatted_code = formatter.format(lexer.lex(code))
+        clipboard_id = "clipboard-#{SecureRandom.hex(16)}"
+        <<~HTML
+          <div class="code_container">
+          <pre><code class="highlight #{lexer_language(language)}">#{formatted_code}</code></pre>
+          <textarea class="clipboard-content" id="#{clipboard_id}">#{clipboard_content(code, language)}</textarea>
+          <button class="clipboard-button" data-clipboard-target="##{clipboard_id}">Copy</button>
+          </div>
         HTML
       end
 
@@ -79,6 +82,17 @@ module RailsGuides
           end
         end
 
+        def clipboard_content(code, language)
+          if language == "bash"
+            prompt_regexp = /^\$ /
+            code = code.split("\n").
+              select { |line| line =~ prompt_regexp }.
+              map { |line| line.gsub(prompt_regexp, "") }.
+              join("\n")
+          end
+          ERB::Util.h(code)
+        end
+
         def convert_notes(body)
           # The following regexp detects special labels followed by a
           # paragraph, perhaps at the end of the document.
diff --git a/guides/source/layout.html.erb b/guides/source/layout.html.erb
index 1b854edccc3..72fe9125870 100644
--- a/guides/source/layout.html.erb
+++ b/guides/source/layout.html.erb
@@ -9,6 +9,7 @@
   <link rel="stylesheet" type="text/css" href="stylesheets/highlight.css" data-turbolinks-track="reload">
   <link href="images/favicon.ico" rel="shortcut icon" type="image/x-icon" />
   <script src="javascripts/turbolinks.js" data-turbolinks-track="reload"></script>
+  <script src="javascripts/clipboard.js" data-turbolinks-track="reload"></script>
   <script src="javascripts/guides.js" data-turbolinks-track="reload"></script>
   <meta property="og:title" content="<%= yield(:page_title) %>" />
   <meta name="description" content="<%= yield(:description) %>" />