Handle white spaces before and after h1 tags when html to markdown.

__tests__/ExpensiMark-Markdown-test.js

@@ -470,13 +470,17 @@ test('Test heading1 markdown replacement', () => {
 test('Test html string to heading1 markdown', () => {
     const testString = '<h1>This is a heading1 because starts with # followed by a space</h1><br />'
     + '<h1>This is also a heading1 because starts with # followed by a space</h1><br />'
-    + 'this is not a heading1 because does not start with #<br />'
-    + '#This is not a heading1 either because starts with a # but has no space after it<br />'
-    + 'this line has no special therefore it cannot be a heading1';
-    const resultString = '# This is a heading1 because starts with # followed by a space\n'
-    + '# This is also a heading1 because starts with # followed by a space\n'
-        + 'this is not a heading1 because does not start with #\n'
-        + '#This is not a heading1 either because starts with a # but has no space after it\n'
-        + 'this line has no special therefore it cannot be a heading1';
+    + 'this is not a <strong>heading1</strong> because does not start with #<br />'
+    + '#This is not a <em>heading1</em> either because starts with a # but has no space after it<br />'
+    + 'this line has no special therefore it cannot be a heading1<br />'
+    + 'this line has a <h1>heading1</h1> in the middle of the line';
+    const resultString = '\n# This is a heading1 because starts with # followed by a space\n'
+    + '\n# This is also a heading1 because starts with # followed by a space\n'
+    + 'this is not a *heading1* because does not start with #\n'
+    + '#This is not a _heading1_ either because starts with a # but has no space after it\n'
+    + 'this line has no special therefore it cannot be a heading1\n'
+    + 'this line has a\n'
+    + '# heading1\n'
+    + 'in the middle of the line';
     expect(parser.htmlToMarkdown(testString)).toBe(resultString);
 });

lib/ExpensiMark.js

@@ -230,8 +230,8 @@ export default class ExpensiMark {
             },
             {
                 name: 'heading1',
-                regex: /<(h1)(?:"[^"]*"|'[^']*'|[^'">])*>(.*?)<\/\1>(?![^<]*(<\/pre>|<\/code>))/gi,
-                replacement: '# $2',
+                regex:/\s*<(h1)(?:"[^"]*"|'[^']*'|[^'">])*>(.*?)<\/\1>(?![^<]*(<\/pre>|<\/code>))\s*/gi,
+                replacement: '\n# $2\n',
             },
             {
                 name: 'italic',