Handle parse error in File::getMethodProperties()

While investigating the cause of a PHP Fatal error while processing some input
in the `PSR12.Functions.ReturnTypeDeclaration` sniff, I noticed that the
`File::getMethodProperties()` method did not return sensible values in for some
parse errors. The input file in question was
`src/Standards/Generic/Tests/Arrays/DisallowLongArraySyntaxUnitTest.2.inc`,
which contains an intentional parse error. The `File::getMethodProperties()`
method claimed that the return type of the `test` function was `<< HEAD`, which
is nonsense.

The change in this commit safeguards from such parse errors and resolves the
issue that was being encountered downstream in the sniff.

Author: fredden

src/Files/File.php

@@ -1781,6 +1781,8 @@ public function getMethodProperties(int $stackPtr)
                 T_TYPE_CLOSE_PARENTHESIS => T_TYPE_CLOSE_PARENTHESIS,
             ];
 
+            $hasColon = false;
+
             for ($i = $this->tokens[$stackPtr]['parenthesis_closer']; $i < $this->numTokens; $i++) {
                 if (($scopeOpener === null && $this->tokens[$i]['code'] === T_SEMICOLON)
                     || ($scopeOpener !== null && $i === $scopeOpener)
@@ -1800,11 +1802,17 @@ public function getMethodProperties(int $stackPtr)
                     continue;
                 }
 
+                if ($this->tokens[$i]['code'] === T_COLON) {
+                    $hasColon = true;
+                    continue;
+                }
+
                 if ($this->tokens[$i]['code'] === T_NULLABLE) {
                     $nullableReturnType = true;
+                    continue;
                 }
 
-                if (isset($valid[$this->tokens[$i]['code']]) === true) {
+                if ($hasColon === true && isset($valid[$this->tokens[$i]['code']]) === true) {
                     if ($returnTypeToken === false) {
                         $returnTypeToken = $i;
                     }

tests/Core/Files/File/GetMethodPropertiesTest.inc

@@ -221,6 +221,10 @@ $closure = function () use /*comment*/ ($a): Type {};
 /* testClosureWithUseMultiParamWithReturnType */
 $closure = function () use ($a, &$b, $c, $d, $e, $f, $g): ?array {};
 
+/* testMissingColonParseError */
+// Intentional parse error.
+$closure = function () null { return null; };
+
 /* testArrowFunctionLiveCoding */
 // Intentional parse error. This has to be the last test in the file.
 $fn = fn

tests/Core/Files/File/GetMethodPropertiesTest.php

@@ -1450,6 +1450,31 @@ public function testClosureWithUseWithReturnType()
     }
 
 
+    /**
+     * Test handling of a parse error where the colon is missing from the return type declaration.
+     *
+     * @return void
+     */
+    public function testMissingColonParseError()
+    {
+        // Offsets are relative to the T_CLOSURE token.
+        $expected = [
+            'scope'                 => 'public',
+            'scope_specified'       => false,
+            'return_type'           => '',
+            'return_type_token'     => false,
+            'return_type_end_token' => false,
+            'nullable_return_type'  => false,
+            'is_abstract'           => false,
+            'is_final'              => false,
+            'is_static'             => false,
+            'has_body'              => true,
+        ];
+
+        $this->getMethodPropertiesTestHelper('/* ' . __FUNCTION__ . ' */', $expected);
+    }
+
+
     /**
      * Test handling of closure declarations with a use variable import with a return type declaration.
      *