Fix whitespace errors

src/Components/Blocks/BlockQuote.php

@@ -7,6 +7,7 @@ use Erusev\Parsedown\AST\StateRenderable;
 use Erusev\Parsedown\Components\Block;
 use Erusev\Parsedown\Components\ContinuableBlock;
 use Erusev\Parsedown\Html\Renderables\Element;
+use Erusev\Parsedown\Html\Renderables\Text;
 use Erusev\Parsedown\Parsedown;
 use Erusev\Parsedown\Parsing\Context;
 use Erusev\Parsedown\Parsing\Line;
@@ -106,6 +107,7 @@ final class BlockQuote implements ContinuableBlock
                 );
 
                 $Renderables = $State->applyTo($StateRenderables);
+                $Renderables[] = new Text("\n");
 
                 return new Element('blockquote', [], $Renderables);
             }

src/Components/Blocks/SetextHeader.php

@@ -49,7 +49,7 @@ final class SetextHeader implements Block
         if ($Context->line()->indent() < 4 && \chop(\chop($Context->line()->text(), " \t"), $Context->line()->text()[0]) === '') {
             $level = $Context->line()->text()[0] === '=' ? 1 : 2;
 
-            return new self($Block->text(), $level);
+            return new self(\trim($Block->text()), $level);
         }
 
         return null;

src/Components/Inlines/Code.php

@@ -40,11 +40,18 @@ final class Code implements Inline
         }
 
         if (\preg_match(
-            '/^(['.$marker.']++)[ ]*+(.*?)[ ]*+(?<!['.$marker.'])\1(?!'.$marker.')/s',
+            '/^(['.$marker.']++)(.*?)(?<!['.$marker.'])\1(?!'.$marker.')/s',
             $Excerpt->text(),
             $matches
         )) {
-            $text = \preg_replace('/[ ]*+\n/', ' ', $matches[2]);
+            $text = \str_replace("\n", ' ', $matches[2]);
+
+            $firstChar = \substr($text, 0, 1);
+            $lastChar = \substr($text, -1);
+
+            if ($firstChar === ' ' && $lastChar === ' ') {
+                $text = \substr(\substr($text, 1), 0, -1);
+            }
 
             return new self($text, \strlen($matches[0]));
         }

tests/commonmark/324-Code_spans.html

@@ -0,0 +1 @@
+<p><code>foo bar   baz</code></p>

tests/commonmark/324-Code_spans.md

@@ -0,0 +1,5 @@
+``
+foo
+bar  
+baz
+``

tests/commonmark/326-Code_spans.html

@@ -0,0 +1 @@
+<p><code>foo   bar  baz</code></p>

tests/commonmark/326-Code_spans.md

@@ -0,0 +1,2 @@
+`foo   bar 
+baz`

tests/commonmark/621-Hard_line_breaks.html

@@ -0,0 +1 @@
+<p><code>code  span</code></p>

tests/commonmark/621-Hard_line_breaks.md

@@ -0,0 +1,2 @@
+`code 
+span`