Breaks improvements and code simplification

lib/markdown2.py

@@ -1362,15 +1362,20 @@ def _run_span_gamut(self, text):
             text = self._do_smart_punctuation(text)
 
         # Do hard breaks:
-        if 'breaks' in self.extras:
-            break_tag = "<br%s\n" % self.empty_element_suffix
-            # do backslashes first because on_newline inserts the break before the newline
-            if self.extras['breaks'].get('on_backslash', False):
-                text = re.sub(r' *\\\n', break_tag, text)
-            if self.extras['breaks'].get('on_newline', False):
-                text = re.sub(r" *\n(?!\<(?:\/?(ul|ol|li))\>)", break_tag, text)
+        on_backslash = self.extras.get('breaks', {}).get('on_backslash', False)
+        on_newline = self.extras.get('breaks', {}).get('on_newline', False)
+
+        if on_backslash and on_newline:
+            pattern = r' *\\?'
+        elif on_backslash:
+            pattern = r'(?: *\\| {2,})'
+        elif on_newline:
+            pattern = r' *'
         else:
-            text = re.sub(r" {2,}\n", " <br%s\n" % self.empty_element_suffix, text)
+            pattern = r' {2,}'
+
+        break_tag = "<br%s\n" % self.empty_element_suffix
+        text = re.sub(pattern + r"\n(?!\<(?:\/?(ul|ol|li))\>)", break_tag, text)
 
         return text
 

test/tm-cases/admonitions.html

@@ -26,7 +26,7 @@
 
 <aside class="admonition important">
     <strong>IMPORTANT</strong>
-    <p>You can also use 3 or more empty lines after an admonition <br />
+    <p>You can also use 3 or more empty lines after an admonition<br />
     to end it</p>
 </aside>
 

test/tm-cases/break_on_backslash.html

@@ -2,4 +2,5 @@
 you to insert a backslash with or
 without a space, which results in<br />
 a hard line break, unless it has \
-been escaped.</p>
+been escaped. It's still possible to<br />
+end the line with two spaces for a line break.</p>

test/tm-cases/break_on_backslash.text

@@ -2,4 +2,5 @@ Github flavoured markdown allows \
 you to insert a backslash with or
 without a space, which results in\
 a hard line break, unless it has \\
-been escaped.
+been escaped. It's still possible to  
+end the line with two spaces for a line break.

test/tm-cases/break_on_newline_and_backslash.html

@@ -1,3 +1,3 @@
 <p>The breaks extra allows you to insert a hard break on newlines.<br />
-You can also insert hard breaks after backslashes<br /><br />
-although this will result in a double break when both are enabled.</p>
+You can also insert hard breaks after backslashes<br />
+which will result in a single break when both are enabled.</p>

test/tm-cases/break_on_newline_and_backslash.text

@@ -1,3 +1,3 @@
 The breaks extra allows you to insert a hard break on newlines.
 You can also insert hard breaks after backslashes \
-although this will result in a double break when both are enabled.
+which will result in a single break when both are enabled.

test/tm-cases/smarty_pants.html

@@ -37,9 +37,9 @@ <h3>Edge case: contractions</h3>
 
 <p>For common contractions, a space single-prime non-space combination should produce an apostrophe (&amp;#8217;) instead of an opening scare quote (&amp;#8216;).</p>
 
-<p>Here is the full list: &#8217;tis, &#8217;twas, &#8217;twer, &#8217;neath, &#8217;o, &#8217;n, &#8217;round, &#8217;bout, &#8217;twixt, &#8217;nuff, &#8217;fraid, &#8217;sup <br />
-The full list, capitalized: &#8217;Tis, &#8217;Twas, &#8217;Twer, &#8217;Neath, &#8217;O, &#8217;N, &#8217;Round, &#8217;Bout, &#8217;Twixt, &#8217;Nuff, &#8217;Fraid, &#8217;Sup <br />
-And normal text: &#8216;random &#8216;stuff &#8216;that &#8216;shouldn&#8217;t &#8216;be &#8216;detected &#8216;as &#8216;contractions <br />
+<p>Here is the full list: &#8217;tis, &#8217;twas, &#8217;twer, &#8217;neath, &#8217;o, &#8217;n, &#8217;round, &#8217;bout, &#8217;twixt, &#8217;nuff, &#8217;fraid, &#8217;sup<br />
+The full list, capitalized: &#8217;Tis, &#8217;Twas, &#8217;Twer, &#8217;Neath, &#8217;O, &#8217;N, &#8217;Round, &#8217;Bout, &#8217;Twixt, &#8217;Nuff, &#8217;Fraid, &#8217;Sup<br />
+And normal text: &#8216;random &#8216;stuff &#8216;that &#8216;shouldn&#8217;t &#8216;be &#8216;detected &#8216;as &#8216;contractions<br />
 And years: &#8217;29 &#8217;91 &#8216;1942 &#8216;2001 &#8216;2010</p>
 
 <p>Like quotation marks, the year shorthand expects a year, e.g. '29, to be followed by whitespace or sentence-ending punctuation.  Numbers like '456.7 will throw it off, but those aren&#8217;t entered very often.</p>

test/tm-cases/spoiler.html

@@ -7,22 +7,22 @@
 <p>[Second]</p>
 
 <blockquote>
-  <p>! But this is <br />
+  <p>! But this is<br />
   not a spoiler</p>
 </blockquote>
 
 <p>[Third]</p>
 
 <blockquote class="spoiler">
-  <p>A multi-line spoiler <br />
+  <p>A multi-line spoiler<br />
   has ! multiple times</p>
 </blockquote>
 
 <p>[Fourth]</p>
 
 <blockquote class="spoiler">
-  <p>Alignment <br />
-  has no effect <br />
+  <p>Alignment<br />
+  has no effect<br />
   on spoilers</p>
 </blockquote>
 

test/tm-cases/wavedrom_no_embed.html

@@ -9,7 +9,7 @@
 <ul>
 <li>More complex diagram
 <ul>
-<li>Inside of nested list <br />
+<li>Inside of nested list<br />
 <script type="WaveDrom">
 { signal: [
     { name: "pclk", wave: 'p.......' },