Fix the extra prompt and the dropped attributes in Command Line examples written in Markdown

src/plugins/command-line/README.md

@@ -164,8 +164,7 @@ d-r--        10/14/2015   5:06 PM            Videos
      data-continuation-str="\" >
 ```
 
-```bash { .command-line data-filter-output="(out)" data-continuation-str="\" }
-export MY_VAR=123
+<pre class="command-line" data-filter-output="(out)" data-continuation-str="\"><code class="language-bash">export MY_VAR=123
 echo "hello"
 (out)hello
 echo one \
@@ -174,8 +173,7 @@ three
 (out)one two three
 (out)
 echo "goodbye"
-(out)goodbye
-```
+(out)goodbye</code></pre>
 
 ## Line continuation with Output (PowerShell)
 

src/plugins/command-line/command-line.js

@@ -35,7 +35,10 @@ const Self = {
 					existingPrompt.remove();
 				}
 
-				const codeLines = env.code.split('\n');
+				// Browsers draw no line after a final line break, which every Markdown code fence ends with,
+				// so it gets no prompt
+				const finalLineBreak = env.code.endsWith('\n') ? '\n' : '';
+				const codeLines = env.code.replace(/\n$/, '').split('\n');
 
 				commandLine.numberOfLines = codeLines.length;
 				const outputLines = (commandLine.outputLines = []);
@@ -104,7 +107,7 @@ const Self = {
 					}
 				}
 
-				env.code = codeLines.join('\n');
+				env.code = codeLines.join('\n') + finalLineBreak;
 			},
 			'before-insert': env => {
 				const commandLine = (env.commandLine ??= {});

tests/plugins/command-line/basic-functionality.js

@@ -0,0 +1,50 @@
+import { assert } from 'chai';
+import { createTestSuite } from '../../helper/prism-dom-util.js';
+
+describe('Command Line', () => {
+	const { it } = createTestSuite({
+		languages: 'bash',
+		plugins: 'command-line',
+	});
+
+	/**
+	 * @param {import('../../types.d.ts').PrismDOM<{}>} dom
+	 * @param {number} expectedPrompts
+	 * @param {string} code
+	 */
+	function test ({ document, Prism }, expectedPrompts, code) {
+		document.body.innerHTML = `<pre class="command-line language-bash"><code>${code}</code></pre>`;
+		Prism.highlightAll();
+
+		assert.strictEqual(
+			document.querySelectorAll('.command-line-prompt > span').length,
+			expectedPrompts
+		);
+	}
+
+	it('should prompt every line', dom => {
+		test(dom, 2, 'cd ~/.vim\nvim vimrc');
+		test(dom, 3, 'cd ~/.vim\n\nvim vimrc');
+	});
+
+	// Markdown code fences end with one
+	it('should not prompt after a final line break', dom => {
+		test(dom, 2, 'cd ~/.vim\nvim vimrc\n');
+		test(dom, 3, 'cd ~/.vim\nvim vimrc\n\n');
+	});
+
+	// Copy to Clipboard copies the element's text
+	it('should keep the final line break in the code', ({ document, Prism }) => {
+		document.body.innerHTML = `<pre class="command-line language-bash"><code>ls\nfile.txt\n</code></pre>`;
+		Prism.highlightAll();
+
+		assert.strictEqual(document.querySelector('code')?.textContent, 'ls\nfile.txt\n');
+	});
+
+	it('should keep output on the last line', ({ document, Prism }) => {
+		document.body.innerHTML = `<pre class="command-line language-bash" data-output="2"><code>ls\nfile.txt\n</code></pre>`;
+		Prism.highlightAll();
+
+		assert.strictEqual(document.querySelector('.token.output')?.textContent, 'file.txt');
+	});
+});