bug #859 [TwigComponent] Fixing bug where traditional blocks aren't handled correctly (weaverryan)

This PR was squashed before being merged into the 2.x branch.

Discussion
----------

[TwigComponent] Fixing bug where traditional blocks aren't handled correctly

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| Tickets       | Fixes part of #844 (comment)
| License       | MIT

Using `{% block traditional_block %}` inside of a `<twig:Component` syntax should now work. However, even though I tried to make the TwigPreLexer a bit more intelligent than just a regex parser, it's reaching its limits of complexity. Even this fix will break down if the user adds extra whitespace - e.g. `{%       block traditional_block %}`. It's likely that `TwigPreLexer` will need to be converted to an actual Lexer -> token stream -> parser type of a system. On the bright side, that would make it easier to integrate into Twig core if we ever chose to do that (the parser wouldn't convert over directly, but the lexer & tokens in theory would).

Cheers!

Commits
-------

2ca9430 [TwigComponent] Fixing bug where traditional blocks aren't handled correctly

Author: weaverryan

src/TwigComponent/src/Twig/TwigPreLexer.php

@@ -52,8 +52,10 @@ public function preLexComponents(string $input, bool $insideOfBlock = false): st
                 }
             }
 
-            if ($this->consume('<twig:')) {
-                $componentName = $this->consumeComponentName();
+            $isTwigHtmlOpening = $this->consume('<twig:');
+            $isTraditionalBlockOpening = false;
+            if ($isTwigHtmlOpening || (0 !== \count($this->currentComponents) && $isTraditionalBlockOpening = $this->consume('{% block'))) {
+                $componentName = $isTraditionalBlockOpening ? 'block' : $this->consumeComponentName();
 
                 if ('block' === $componentName) {
                     // if we're already inside the "default" block, let's close it
@@ -63,6 +65,15 @@ public function preLexComponents(string $input, bool $insideOfBlock = false): st
                         $this->currentComponents[\count($this->currentComponents) - 1]['hasDefaultBlock'] = false;
                     }
 
+                    if ($isTraditionalBlockOpening) {
+                        // add what we've consumed so far
+                        $output .= '{% block';
+                        $output .= $this->consumeUntil('%}');
+                        $output .= $this->consumeUntilEndBlock();
+
+                        continue;
+                    }
+
                     $output .= $this->consumeBlock($componentName);
 
                     continue;
@@ -119,7 +130,7 @@ public function preLexComponents(string $input, bool $insideOfBlock = false): st
                 continue;
             }
 
-            $char = $this->consumeChar();
+            $char = $this->input[$this->position];
             if ("\n" === $char) {
                 ++$this->line;
             }
@@ -128,11 +139,13 @@ public function preLexComponents(string $input, bool $insideOfBlock = false): st
             if (!empty($this->currentComponents)
                 && !$this->currentComponents[\count($this->currentComponents) - 1]['hasDefaultBlock']
                 && preg_match('/\S/', $char)
+                && !$this->check('{% block')
             ) {
                 $output .= $this->addDefaultBlock();
             }
 
             $output .= $char;
+            $this->consumeChar();
         }
 
         if (!empty($this->currentComponents)) {
@@ -374,10 +387,24 @@ private function consumeUntilEndBlock(): string
                 }
             }
 
+            if ('{% endblock %}' === substr($this->input, $this->position, 14)) {
+                if (1 === $depth) {
+                    // in this case, we want to advanced ALL the way beyond the endblock
+                    $this->position += 14;
+                    break;
+                } else {
+                    --$depth;
+                }
+            }
+
             if ('<twig:block' === substr($this->input, $this->position, 11)) {
                 ++$depth;
             }
 
+            if ('{% block' === substr($this->input, $this->position, 8)) {
+                ++$depth;
+            }
+
             if ("\n" === $this->input[$this->position]) {
                 ++$this->line;
             }

src/TwigComponent/tests/Unit/TwigPreLexerTest.php

@@ -52,6 +52,16 @@ public function getLexTests(): iterable
             '{% component \'foo\' %}{% block foo_block %}Foo{% endblock %}{% endcomponent %}',
         ];
 
+        yield 'component_with_traditional_block' => [
+            '<twig:foo>{% block foo_block %}Foo{% endblock %}</twig:foo>',
+            '{% component \'foo\' %}{% block foo_block %}Foo{% endblock %}{% endcomponent %}',
+        ];
+
+        yield 'traditional_blocks_around_component_do_not_confuse' => [
+            'Hello {% block foo_block %}Foo{% endblock %}<twig:foo />{% block bar_block %}Bar{% endblock %}',
+            'Hello {% block foo_block %}Foo{% endblock %}{{ component(\'foo\') }}{% block bar_block %}Bar{% endblock %}',
+        ];
+
         yield 'component_with_embedded_component_inside_block' => [
             '<twig:foo><twig:block name="foo_block"><twig:bar /></twig:block></twig:foo>',
             '{% component \'foo\' %}{% block foo_block %}{{ component(\'bar\') }}{% endblock %}{% endcomponent %}',