fix: preserve whitespace-only code spans in Markdown export

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 #### Review fixes
 
+- Preserved code spans containing three or more spaces when exporting Todo files to Markdown.
 - Offered known tag-argument completions inside auto-closed parentheses without inserting a duplicate closing parenthesis.
 - Preserved punctuation immediately before a completion or elapsed-time tag when reopening a task.
 - Rejected invalid ISO calendar dates in time estimates instead of silently rolling them into another month.

src/utils/markdown-export.ts

@@ -15,7 +15,12 @@ const escapeMarkdownText = (text: string): string => text.replace(/[!-/:-@[-`{-~
 const renderCodeSpan = (content: string): string => {
   if (!content) return '<code></code>';
 
-  const needsPadding = (content.startsWith(' ') || content.endsWith(' ')) && !/^ +$/.test(content),
+  // Markdown trims a space from each end of runs longer than two spaces,
+  // even when the code span contains nothing but spaces.
+  const spacesOnly = /^ +$/.test(content),
+    needsPadding = spacesOnly
+      ? content.length > 2
+      : content.startsWith(' ') || content.endsWith(' '),
     padding = needsPadding ? ' ' : '';
 
   return `\`${padding}${content}${padding}\``;

test/markdown-export.spec.ts

@@ -95,6 +95,15 @@ describe('Todo Markdown export', () => {
     expect(html).to.include('<code></code> <code> </code> <code> code </code>');
   });
 
+  it('preserves code spans containing three or more spaces', () => {
+    const markdown = renderTodoMarkdown('Tasks', [
+        { kind: 'comment', level: 0, text: '`   ` `    `' },
+      ]),
+      html = new MarkdownIt({ html: true }).render(markdown);
+
+    expect(html).to.include('<code>   </code> <code>    </code>');
+  });
+
   it('preserves HTML-like text and entities in rendered Markdown', () => {
     const markdown = renderTodoMarkdown('Plan <T> &copy;', [
         { kind: 'project', level: 0, text: 'Project <T> &copy;' },