Merge pull request #53 from xp-framework/feature/generic-class-resolu…

…tion Add syntactic support for `T<string>::class`
xp-framework · Aug 4, 2024 · 9481a4e · 9481a4e
2 parents 8dbdcdd + 9467b87
commit 9481a4e
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Showing 3 changed files with 71 additions and 4 deletions.
diff --git a/src/main/php/lang/ast/syntax/PHP.class.php b/src/main/php/lang/ast/syntax/PHP.class.php
@@ -171,7 +171,7 @@ public function __construct() {
         $expr= new InvokeExpression($expr, $arguments, $token->line);
       }
 
-      return new ScopeExpression($scope, $expr, $left->line);
+      return new ScopeExpression($scope, $expr, $token->line);
     });
 
     $this->infix('(', 100, function($parse, $token, $left) {
@@ -264,7 +264,7 @@ public function __construct() {
         $parse->forward();
         $skipped[]= $parse->token;
       }
-      $parse->queue= $parse->queue ? array_merge($skipped, $parse->queue) : $skipped;
+      $parse->queue= $parse->queue ? [...$skipped, ...$parse->queue] : $skipped;
 
       if ($cast && ('operator' !== $parse->token->kind || '(' === $parse->token->value || '[' === $parse->token->value)) {
         $parse->forward();
@@ -482,6 +482,40 @@ public function __construct() {
     });
 
     $this->prefix('(name)', 0, function($parse, $token) {
+      static $types= ['(' => 1, ')' => 1, ',' => 1, '?' => 1, ':' => 1, '|' => 1, '&' => 1];
+
+      // Disambiguate `Class<T>` from `const < expr` by looking ahead
+      if ('<' === $parse->token->value) {
+        $generic= true;
+        $level= 1;
+        $skipped= [$parse->token];
+        while ($level > 0) {
+          $parse->forward();
+          $skipped[]= $parse->token;
+
+          if ('<' === $parse->token->symbol->id) {
+            $level++;
+          } else if ('<?' === $parse->token->symbol->id) {
+            $level++;
+          } else if ('>' === $parse->token->symbol->id) {
+            $level--;
+          } else if ('>>' === $parse->token->symbol->id) {
+            $level-= 2;
+          } else if ('name' !== $parse->token->kind && !isset($types[$parse->token->value])) {
+            $generic= false;
+            break;
+          }
+        }
+
+        $parse->queue= $parse->queue ? [...$skipped, ...$parse->queue] : $skipped;
+        if ($generic) {
+          $parse->token= $token;
+          return $this->type($parse, false);
+        }
+
+        $parse->forward();
+      }
+
       return new Literal($token->value, $token->line);
     });
 

diff --git a/src/test/php/lang/ast/unittest/parse/MembersTest.class.php b/src/test/php/lang/ast/unittest/parse/MembersTest.class.php
@@ -19,7 +19,7 @@
   Variable,
   Parameter
 };
-use lang\ast\types\{IsFunction, IsLiteral, IsNullable, IsUnion, IsValue};
+use lang\ast\types\{IsFunction, IsLiteral, IsNullable, IsUnion, IsValue, IsGeneric};
 use test\{Assert, Test, Values};
 
 class MembersTest extends ParseTest {
@@ -297,6 +297,14 @@ public function class_resolution() {
     );
   }
 
+  #[Test]
+  public function generic_class_resolution() {
+    $this->assertParsed(
+      [new ScopeExpression(new IsGeneric(new IsValue('\\A'), [new IsValue('\\T')]), new Literal('class', self::LINE), self::LINE)],
+      'A<T>::class;'
+    );
+  }
+
   #[Test]
   public function instance_method_invocation() {
     $this->assertParsed(

diff --git a/src/test/php/lang/ast/unittest/parse/OperatorTest.class.php b/src/test/php/lang/ast/unittest/parse/OperatorTest.class.php
@@ -18,7 +18,7 @@
   UnaryExpression,
   Variable
 };
-use lang\ast\types\{IsExpression, IsValue};
+use lang\ast\types\{IsExpression, IsGeneric, IsValue};
 use test\{Assert, Test, Values};
 
 class OperatorTest extends ParseTest {
@@ -283,6 +283,18 @@ public function precedence_of_not_and_instance_of() {
     );
   }
 
+  #[Test]
+  public function instanceof_generic() {
+    $this->assertParsed(
+      [new InstanceOfExpression(
+        new Variable('this', self::LINE),
+        new IsGeneric(new IsValue('self'), [new IsValue('T')]),
+        self::LINE
+      )],
+      '$this instanceof self<T>;'
+    );
+  }
+
   #[Test, Values(['+', '-', '~'])]
   public function precedence_of_prefix($operator) {
     $this->assertParsed(
@@ -332,4 +344,17 @@ public function multiple_semicolons() {
       ';; $a= 1 ;;; $b= 2;'
     );
   }
+
+  #[Test]
+  public function const_less_than_const() {
+    $this->assertParsed(
+      [new BinaryExpression(
+        new Literal('a', self::LINE),
+        '<',
+        new Literal('b', self::LINE),
+        self::LINE
+      )],
+      'a < b;'
+    );
+  }
 }