Replace most empty() calls

src/ExpressionParser.php

@@ -621,7 +621,7 @@ class ExpressionParser
 
         $stream->expect(Token::PUNCTUATION_TYPE, '(', 'A list of arguments must begin with an opening parenthesis');
         while (!$stream->test(Token::PUNCTUATION_TYPE, ')')) {
-            if (!empty($args)) {
+            if ($args) {
                 $stream->expect(Token::PUNCTUATION_TYPE, ',', 'Arguments must be separated by a comma');
 
                 // if the comma above was a trailing comma, early exit the argument parse loop

src/Extension/CoreExtension.php

@@ -545,7 +545,7 @@ final class CoreExtension extends AbstractExtension
         }
 
         $asString = (string) $date;
-        if (ctype_digit($asString) || (!empty($asString) && '-' === $asString[0] && ctype_digit(substr($asString, 1)))) {
+        if (ctype_digit($asString) || (isset($asString[0]) && '-' === $asString[0] && ctype_digit(substr($asString, 1)))) {
             $date = new \DateTime('@'.$date);
         } else {
             $date = new \DateTime($date, $this->getTimezone());
@@ -1616,7 +1616,7 @@ final class CoreExtension extends AbstractExtension
                 } elseif (\is_object($object)) {
                     $message = \sprintf('Impossible to access a key "%s" on an object of class "%s" that does not implement ArrayAccess interface.', $item, \get_class($object));
                 } elseif (\is_array($object)) {
-                    if (empty($object)) {
+                    if (!$object) {
                         $message = \sprintf('Key "%s" does not exist as the sequence/mapping is empty.', $arrayItem);
                     } else {
                         $message = \sprintf('Key "%s" for sequence/mapping with keys "%s" does not exist.', $arrayItem, implode(', ', array_keys($object)));

src/Lexer.php

@@ -217,7 +217,7 @@ class Lexer
 
         $this->pushToken(Token::EOF_TYPE);
 
-        if (!empty($this->brackets)) {
+        if ($this->brackets) {
             [$expect, $lineno] = array_pop($this->brackets);
             throw new SyntaxError(\sprintf('Unclosed "%s".', $expect), $lineno, $this->source);
         }
@@ -292,7 +292,7 @@ class Lexer
 
     private function lexBlock(): void
     {
-        if (empty($this->brackets) && preg_match($this->regexes['lex_block'], $this->code, $match, 0, $this->cursor)) {
+        if (!$this->brackets && preg_match($this->regexes['lex_block'], $this->code, $match, 0, $this->cursor)) {
             $this->pushToken(Token::BLOCK_END_TYPE);
             $this->moveCursor($match[0]);
             $this->popState();
@@ -303,7 +303,7 @@ class Lexer
 
     private function lexVar(): void
     {
-        if (empty($this->brackets) && preg_match($this->regexes['lex_var'], $this->code, $match, 0, $this->cursor)) {
+        if (!$this->brackets && preg_match($this->regexes['lex_var'], $this->code, $match, 0, $this->cursor)) {
             $this->pushToken(Token::VAR_END_TYPE);
             $this->moveCursor($match[0]);
             $this->popState();
@@ -360,7 +360,7 @@ class Lexer
             }
             // closing bracket
             elseif (str_contains(')]}', $this->code[$this->cursor])) {
-                if (empty($this->brackets)) {
+                if (!$this->brackets) {
                     throw new SyntaxError(\sprintf('Unexpected "%s".', $this->code[$this->cursor]), $this->lineno, $this->source);
                 }
 

src/Node/Expression/CallExpression.php

@@ -208,7 +208,7 @@ abstract class CallExpression extends AbstractExpression
             } elseif ($callableParameter->isDefaultValueAvailable()) {
                 $optionalArguments[] = new ConstantExpression($callableParameter->getDefaultValue(), -1);
             } elseif ($callableParameter->isOptional()) {
-                if (empty($parameters)) {
+                if (!$parameters) {
                     break;
                 } else {
                     $missingArguments[] = $name;
@@ -235,7 +235,7 @@ abstract class CallExpression extends AbstractExpression
             }
         }
 
-        if (!empty($parameters)) {
+        if ($parameters) {
             $unknownParameter = null;
             foreach ($parameters as $parameter) {
                 if ($parameter instanceof Node) {

src/Test/IntegrationTestCase.php

@@ -149,7 +149,7 @@ abstract class IntegrationTestCase extends TestCase
             $tests[] = [str_replace($fixturesDir.'/', '', $file), $message, $condition, $templates, $exception, $outputs, $deprecation];
         }
 
-        if ($legacyTests && empty($tests)) {
+        if ($legacyTests && !$tests) {
             // add a dummy test to avoid a PHPUnit message
             return [['not', '-', '', [], '', []]];
         }