Optimize compiled code for "set" tag

Author: fabpot

src/Node/SetNode.php

@@ -33,9 +33,15 @@ public function __construct(bool $capture, Node $names, Node $values, int $linen
         $safe = false;
         if ($capture) {
             $safe = true;
-            if ($values instanceof TextNode) {
+            if (Node::class === get_class($values) && !count($values)) {
+                $values = new ConstantExpression('', $values->getTemplateLine());
+                $capture = false;
+            } elseif ($values instanceof TextNode) {
                 $values = new ConstantExpression($values->getAttribute('data'), $values->getTemplateLine());
                 $capture = false;
+            } elseif ($values instanceof PrintNode && $values->getNode('expr') instanceof ConstantExpression) {
+                $values = new ConstantExpression($values->getNode('expr')->getAttribute('value'), $values->getTemplateLine());
+                $capture = false;
             } else {
                 $values = new CaptureNode($values, $values->getTemplateLine());
             }
@@ -78,11 +84,23 @@ public function compile(Compiler $compiler): void
                 $compiler->raw(']');
             } else {
                 if ($this->getAttribute('safe')) {
-                    $compiler
-                        ->raw("('' === \$tmp = ")
-                        ->subcompile($this->getNode('values'))
-                        ->raw(") ? '' : new Markup(\$tmp, \$this->env->getCharset())")
-                    ;
+                    if ($this->getNode('values') instanceof ConstantExpression) {
+                        if ('' === $this->getNode('values')->getAttribute('value')) {
+                            $compiler->raw('""');
+                        } else {
+                            $compiler
+                                ->raw('new Markup(')
+                                ->subcompile($this->getNode('values'))
+                                ->raw(', $this->env->getCharset())')
+                            ;
+                        }
+                    } else {
+                        $compiler
+                            ->raw("('' === \$tmp = ")
+                            ->subcompile($this->getNode('values'))
+                            ->raw(") ? '' : new Markup(\$tmp, \$this->env->getCharset())")
+                        ;
+                    }
                 } else {
                     $compiler->subcompile($this->getNode('values'));
                 }

tests/Node/SetTest.php

@@ -77,7 +77,25 @@ public static function provideTests(): iterable
         $node = new SetNode(true, $names, $values, 1);
         $tests[] = [$node, <<<EOF
 // line 1
-\$context["foo"] = ('' === \$tmp = "foo") ? '' : new Markup(\$tmp, \$this->env->getCharset());
+\$context["foo"] = new Markup("foo", \$this->env->getCharset());
+EOF
+        ];
+
+        $names = new Node([new AssignNameExpression('foo', 1)], [], 1);
+        $values = new TextNode('', 1);
+        $node = new SetNode(true, $names, $values, 1);
+        $tests[] = [$node, <<<EOF
+// line 1
+\$context["foo"] = "";
+EOF
+        ];
+
+        $names = new Node([new AssignNameExpression('foo', 1)], [], 1);
+        $values = new PrintNode(new ConstantExpression('foo', 1), 1);
+        $node = new SetNode(true, $names, $values, 1);
+        $tests[] = [$node, <<<EOF
+// line 1
+\$context["foo"] = new Markup("foo", \$this->env->getCharset());
 EOF
         ];