Fix AlwaysReturnSniff for missing return statement

Now properly catches filter callbacks that don't `return` _anywhere_ inside the function body

Author: nickdaugherty

WordPressVIPMinimum/Sniffs/Filters/AlwaysReturnSniff.php

@@ -228,7 +228,7 @@ private function processFunctionBody( $stackPtr ) {
 			);
 		}
 
-		if ( 0 < $insideIfConditionalReturn && 0 === $outsideConditionalReturn ) {
+		if ( 0 <= $insideIfConditionalReturn && 0 === $outsideConditionalReturn ) {
 			$this->phpcsFile->AddWarning( sprintf( 'Please, make sure that a callback to `%s` filter is always returning some value.', $filterName ), $functionBodyScopeStart, 'missingReturnStatement' );
 		}
 	}

WordPressVIPMinimum/Tests/Filters/AlwaysReturnUnitTest.inc

@@ -100,4 +100,10 @@ if ( 1 === 1 ) {
 	add_filter( 'another_good_example_closure', function () {
 		return 'hello';
 	} );
-}
+}
+
+add_filter( 'bad_example_closure_with_no_returns', function( $input ) {
+	$input = $input . ' hello!';
+
+	// But we never return _anywhere_
+}, 10, 2 );

WordPressVIPMinimum/Tests/Filters/AlwaysReturnUnitTest.php

@@ -35,6 +35,7 @@ public function getWarningList() {
 			49 => 1,
 			88 => 1,
 			95 => 1,
+			105 => 1,
 		);
 	}