Desktop: Fixes #8530: Rich text editor: Use fewer  s in markdo…

…wn while still preserving initial paragraph indentation (#8529)

packages/app-cli/tests/html_to_md/bold_italic_with_spaces.md

@@ -1 +1 @@
-   **A test...** Test
+   **A test...** Test

packages/turndown/src/commonmark-rules.js

@@ -1,4 +1,4 @@
-import { repeat, isCodeBlockSpecialCase1, isCodeBlockSpecialCase2, isCodeBlock, getStyleProp } from './utilities'
+import { repeat, isCodeBlockSpecialCase1, isCodeBlockSpecialCase2, isCodeBlock, getStyleProp, htmlEscapeLeadingNonbreakingSpace } from './utilities'
 const Entities = require('html-entities').AllHtmlEntities;
 const htmlentities = (new Entities()).encode;
 
@@ -25,6 +25,13 @@ rules.paragraph = {
   filter: 'p',
 
   replacement: function (content) {
+    // If the line starts with a nonbreaking space, replace it. By default, the
+    // markdown renderer removes leading non-HTML-escaped nonbreaking spaces. However,
+    // because the space is nonbreaking, we want to keep it.
+    // \u00A0 is a nonbreaking space.
+    const leadingNonbreakingSpace = /^\u{00A0}/ug;
+    content = content.replace(leadingNonbreakingSpace, ' ');
+
     return '\n\n' + content + '\n\n'
   }
 }

packages/turndown/src/turndown.js

@@ -36,7 +36,6 @@ export default function TurndownService (options) {
     linkReferenceStyle: 'full',
     anchorNames: [],
     br: '  ',
-    nonbreakingSpace: ' ',
     disableEscapeContent: false,
     preformattedCode: false,
     blankReplacement: function (content, node) {
@@ -216,15 +215,10 @@ function replacementForNode (node) {
   var whitespace = node.flankingWhitespace
   if (whitespace.leading || whitespace.trailing) content = content.trim()
 
-  const replaceNonbreakingSpaces = space => {
-    // \u{00A0} is a nonbreaking space
-    return space.replace(/\u{00A0}/ug, this.options.nonbreakingSpace);
-  };
-
   return (
-    replaceNonbreakingSpaces(whitespace.leading) +
-    replaceNonbreakingSpaces(rule.replacement(content, node, this.options)) +
-    replaceNonbreakingSpaces(whitespace.trailing)
+    whitespace.leading +
+    rule.replacement(content, node, this.options) +
+    whitespace.trailing
   )
 }