Support scalar type declarations

grammar/php7.y

@@ -330,7 +330,7 @@ parameter:
 ;
 
 type:
-      name                                                  { $$ = $1; }
+      name                                                  { $$ = $this->handleScalarTypes($1); }
     | T_ARRAY                                               { $$ = 'array'; }
     | T_CALLABLE                                            { $$ = 'callable'; }
 ;

lib/PhpParser/Parser/Php7.php

@@ -1623,7 +1623,7 @@ class Php7 extends \PhpParser\ParserAbstract
     }
 
     protected function reduceRule203() {
-         $this->semValue = $this->semStack[$this->stackPos-(1-1)];
+         $this->semValue = $this->handleScalarTypes($this->semStack[$this->stackPos-(1-1)]);
     }
 
     protected function reduceRule204() {

lib/PhpParser/ParserAbstract.php

@@ -6,6 +6,8 @@ namespace PhpParser;
  * This parser is based on a skeleton written by Moriyoshi Koizumi, which in
  * turn is based on work by Masato Bito.
  */
+use PhpParser\Node\Name;
+
 abstract class ParserAbstract implements ParserInterface
 {
     const SYMBOL_NONE = -1;
@@ -461,4 +463,20 @@ abstract class ParserAbstract implements ParserInterface
         }
         return $style;
     }
+
+    protected function handleScalarTypes(Name $name) {
+        $scalarTypes = [
+            'bool'   => true,
+            'int'    => true,
+            'float'  => true,
+            'string' => true,
+        ];
+
+        if (!$name->isUnqualified()) {
+            return $name;
+        }
+
+        $lowerName = strtolower($name->toString());
+        return isset($scalarTypes[$lowerName]) ? $lowerName : $name;
+    }
 }

test/code/parser/stmt/function/scalarTypeDeclarations.test

@@ -0,0 +1,45 @@
+Scalar type declarations
+-----
+<?php
+function test(bool $a, Int $b, FLOAT $c, StRiNg $d) {}
+-----
+!!php7
+array(
+    0: Stmt_Function(
+        byRef: false
+        name: test
+        params: array(
+            0: Param(
+                type: bool
+                byRef: false
+                variadic: false
+                name: a
+                default: null
+            )
+            1: Param(
+                type: int
+                byRef: false
+                variadic: false
+                name: b
+                default: null
+            )
+            2: Param(
+                type: float
+                byRef: false
+                variadic: false
+                name: c
+                default: null
+            )
+            3: Param(
+                type: string
+                byRef: false
+                variadic: false
+                name: d
+                default: null
+            )
+        )
+        returnType: null
+        stmts: array(
+        )
+    )
+)