[PHP 8.3] Support dynamic class const fetch

RFC: https://wiki.php.net/rfc/dynamic_class_constant_fetch
nikic · Jul 30, 2023 · cfc54e3 · cfc54e3
1 parent 05e84f7
commit cfc54e3
Show file tree

Hide file tree

Showing 8 changed files with 480 additions and 417 deletions.
diff --git a/grammar/php7.y b/grammar/php7.y
@@ -1046,6 +1046,8 @@ constant:
 class_constant:
       class_name_or_var T_PAAMAYIM_NEKUDOTAYIM identifier_maybe_reserved
           { $$ = Expr\ClassConstFetch[$1, $3]; }
+    | class_name_or_var T_PAAMAYIM_NEKUDOTAYIM '{' expr '}'
+          { $$ = Expr\ClassConstFetch[$1, $4]; }
     /* We interpret an isolated FOO:: as an unfinished class constant fetch. It could also be
        an unfinished static property fetch or unfinished scoped call. */
     | class_name_or_var T_PAAMAYIM_NEKUDOTAYIM error

diff --git a/lib/PhpParser/BuilderFactory.php b/lib/PhpParser/BuilderFactory.php
@@ -349,15 +349,15 @@ public function propertyFetch(Expr $var, $name) : Expr\PropertyFetch {
     /**
      * Creates a class constant fetch node.
      *
-     * @param string|Name|Expr  $class Class name
-     * @param string|Identifier $name  Constant name
+     * @param string|Name|Expr $class Class name
+     * @param string|Identifier|Expr $name  Constant name
      *
      * @return Expr\ClassConstFetch
      */
     public function classConstFetch($class, $name): Expr\ClassConstFetch {
         return new Expr\ClassConstFetch(
             BuilderHelpers::normalizeNameOrExpr($class),
-            BuilderHelpers::normalizeIdentifier($name)
+            BuilderHelpers::normalizeIdentifierOrExpr($name)
         );
     }
 

diff --git a/lib/PhpParser/Node/Expr/ClassConstFetch.php b/lib/PhpParser/Node/Expr/ClassConstFetch.php
@@ -10,15 +10,15 @@ class ClassConstFetch extends Expr
 {
     /** @var Name|Expr Class name */
     public $class;
-    /** @var Identifier|Error Constant name */
+    /** @var Identifier|Expr|Error Constant name */
     public $name;
 
     /**
      * Constructs a class const fetch node.
      *
-     * @param Name|Expr               $class      Class name
-     * @param string|Identifier|Error $name       Constant name
-     * @param array                   $attributes Additional attributes
+     * @param Name|Expr                    $class      Class name
+     * @param string|Identifier|Expr|Error $name       Constant name
+     * @param array                        $attributes Additional attributes
      */
     public function __construct($class, $name, array $attributes = []) {
         $this->attributes = $attributes;
@@ -29,7 +29,7 @@ public function __construct($class, $name, array $attributes = []) {
     public function getSubNodeNames() : array {
         return ['class', 'name'];
     }
-    
+
     public function getType() : string {
         return 'Expr_ClassConstFetch';
     }

diff --git a/lib/PhpParser/Parser/Php7.php b/lib/PhpParser/Parser/Php7.php
diff --git a/lib/PhpParser/PrettyPrinter/Standard.php b/lib/PhpParser/PrettyPrinter/Standard.php
@@ -606,7 +606,7 @@ protected function pExpr_ConstFetch(Expr\ConstFetch $node) {
     }
 
     protected function pExpr_ClassConstFetch(Expr\ClassConstFetch $node) {
-        return $this->pDereferenceLhs($node->class) . '::' . $this->p($node->name);
+        return $this->pDereferenceLhs($node->class) . '::' . $this->pObjectProperty($node->name);
     }
 
     protected function pExpr_PropertyFetch(Expr\PropertyFetch $node) {

diff --git a/test/PhpParser/BuilderFactoryTest.php b/test/PhpParser/BuilderFactoryTest.php
@@ -210,6 +210,10 @@ public function testConstFetches() {
             new Expr\ClassConstFetch(new Expr\Variable('foo'), new Identifier('BAR')),
             $factory->classConstFetch(new Expr\Variable('foo'), 'BAR')
         );
+        $this->assertEquals(
+            new Expr\ClassConstFetch(new Name('Foo'), new Expr\Variable('foo')),
+            $factory->classConstFetch('Foo', $factory->var('foo'))
+        );
     }
 
     public function testVar() {
@@ -243,7 +247,7 @@ public function testPropertyFetch() {
     public function testInvalidIdentifier() {
         $this->expectException(\LogicException::class);
         $this->expectExceptionMessage('Expected string or instance of Node\Identifier');
-        (new BuilderFactory())->classConstFetch('Foo', new Expr\Variable('foo'));
+        (new BuilderFactory())->classConstFetch('Foo', new Name('foo'));
     }
 
     public function testInvalidIdentifierOrExpr() {

diff --git a/test/code/parser/expr/dynamicClassConst.test b/test/code/parser/expr/dynamicClassConst.test
@@ -0,0 +1,43 @@
+Dynamic class constant fetch
+-----
+<?php
+Foo::{bar()};
+$foo::{bar()};
+-----
+!!php7
+array(
+    0: Stmt_Expression(
+        expr: Expr_ClassConstFetch(
+            class: Name(
+                parts: array(
+                    0: Foo
+                )
+            )
+            name: Expr_FuncCall(
+                name: Name(
+                    parts: array(
+                        0: bar
+                    )
+                )
+                args: array(
+                )
+            )
+        )
+    )
+    1: Stmt_Expression(
+        expr: Expr_ClassConstFetch(
+            class: Expr_Variable(
+                name: foo
+            )
+            name: Expr_FuncCall(
+                name: Name(
+                    parts: array(
+                        0: bar
+                    )
+                )
+                args: array(
+                )
+            )
+        )
+    )
+)
diff --git a/test/code/prettyPrinter/expr/dynamicClassConstFetch.test b/test/code/prettyPrinter/expr/dynamicClassConstFetch.test
@@ -0,0 +1,9 @@
+Dynamic class constant fetch
+-----
+<?php
+Foo::{bar()};
+$foo::{bar()};
+-----
+!!php7
+Foo::{bar()};
+$foo::{bar()};