Add TypeSpec\varray_or_darray<T> and tests

Author: fredemmott

src/TypeSpec.hack

@@ -170,3 +170,9 @@ function vec_like_array<Tv>(TypeSpec<Tv> $tsv): TypeSpec<array<Tv>> {
 function vector<Tv>(TypeSpec<Tv> $inner): TypeSpec<Vector<Tv>> {
   return new __Private\VectorSpec(Vector::class, $inner);
 }
+
+function varray_or_darray<Tv>(
+  TypeSpec<Tv> $inner,
+): TypeSpec<varray_or_darray<Tv>> {
+  return new __Private\VArrayOrDArraySpec($inner);
+}

src/TypeSpec/__Private/ArrayKeySpec.hack

@@ -15,9 +15,4 @@ final class ArrayKeySpec extends UnionSpec<arraykey> {
   public function __construct() {
     parent::__construct('arraykey', new StringSpec(), new IntSpec());
   }
-
-  <<__Override>>
-  public function toString(): string {
-    return 'arraykey';
-  }
 }

src/TypeSpec/__Private/NumSpec.hack

@@ -15,9 +15,4 @@ final class NumSpec extends UnionSpec<num> {
   public function __construct() {
     parent::__construct('num', new IntSpec(), new FloatSpec());
   }
-
-  <<__Override>>
-  public function toString(): string {
-    return 'num';
-  }
 }

src/TypeSpec/__Private/UnionSpec.hack

@@ -33,8 +33,11 @@ abstract class UnionSpec<+T> extends TypeSpec<T> {
         // try next
       }
     }
-    throw
-      TypeCoercionException::withValue($this->getTrace(), $this->name, $value);
+    throw TypeCoercionException::withValue(
+      $this->getTrace(),
+      $this->name,
+      $value,
+    );
   }
 
   <<__Override>>
@@ -46,7 +49,15 @@ abstract class UnionSpec<+T> extends TypeSpec<T> {
         // try next
       }
     }
-    throw
-      IncorrectTypeException::withValue($this->getTrace(), $this->name, $value);
+    throw IncorrectTypeException::withValue(
+      $this->getTrace(),
+      $this->name,
+      $value,
+    );
+  }
+
+  <<__Override>>
+  public function toString(): string {
+    return $this->name;
   }
 }

src/TypeSpec/__Private/VArrayOrDArraySpec.hack

@@ -0,0 +1,28 @@
+/*
+ *  Copyright (c) 2016, Fred Emmott
+ *  Copyright (c) 2017-present, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the MIT license found in the
+ *  LICENSE file in the root directory of this source tree.
+ *
+ */
+
+namespace Facebook\TypeSpec\__Private;
+
+use namespace Facebook\TypeSpec;
+
+final class VArrayOrDArraySpec<T> extends UnionSpec<varray_or_darray<T>> {
+  public function __construct(private TypeSpec\TypeSpec<T> $inner) {
+    parent::__construct(
+      'varray_or_darray',
+      TypeSpec\darray(TypeSpec\arraykey(), $inner),
+      TypeSpec\varray($inner),
+    );
+  }
+
+  <<__Override>>
+  public function toString(): string {
+    return 'varray_or_darray<'.$this->inner->toString().'>';
+  }
+}

tests/VArrayOrDArraySpecTest.hack

@@ -0,0 +1,77 @@
+/*
+ *  Copyright (c) 2016, Fred Emmott
+ *  Copyright (c) 2017-present, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the MIT license found in the
+ *  LICENSE file in the root directory of this source tree.
+ *
+ */
+
+namespace Facebook\TypeAssert;
+
+use namespace Facebook\TypeSpec;
+use type Facebook\TypeSpec\TypeSpec;
+use function Facebook\FBExpect\expect;
+
+final class VArrayOrDArraySpecTest
+  extends TypeSpecTest<varray_or_darray<mixed>> {
+  <<__Override>>
+  public function getTypeSpec(): TypeSpec<varray_or_darray<int>> {
+    return TypeSpec\varray_or_darray(TypeSpec\int());
+  }
+
+  <<__Override>>
+  public function getValidCoercions(): vec<(mixed, varray_or_darray<int>)> {
+    return vec[
+      tuple(vec[], varray[]),
+      tuple(vec['123'], varray[123]),
+      tuple(varray['123'], varray[123]),
+      tuple(varray[123], varray[123]),
+      tuple(dict['foo' => '456'], darray['foo' => 456]),
+      tuple(Vector {123}, varray[123]),
+      tuple(darray['foo' => 123], darray['foo' => 123]),
+      tuple(keyset['123'], darray['123' => 123]),
+    ];
+  }
+
+  <<__Override>>
+  public function getInvalidCoercions(): vec<(mixed)> {
+    return vec[
+      tuple(false),
+      tuple(123),
+      tuple(varray['foo']),
+      tuple(vec['foo']),
+      tuple(keyset['foo']),
+      tuple(darray[123 => 'foo']),
+    ];
+  }
+
+  <<__Override>>
+  public function getToStringExamples(
+  ): vec<(TypeSpec<varray_or_darray<mixed>>, string)> {
+    return vec[
+      tuple(
+        TypeSpec\varray_or_darray(TypeSpec\string()),
+        'varray_or_darray<string>',
+      ),
+      tuple(TypeSpec\varray_or_darray(TypeSpec\int()), 'varray_or_darray<int>'),
+    ];
+  }
+
+  public function testSubtyping(): void {
+    $varray = (
+      (): varray<int> ==>
+        TypeSpec\varray(TypeSpec\int())->assertType(varray[123])
+    )();
+    $darray = (
+      (): darray<arraykey, int> ==>
+        TypeSpec\darray(TypeSpec\arraykey(), TypeSpec\int())
+          ->assertType(darray['foo' => 123])
+    )();
+    $widened_varray = ((): varray_or_darray<int> ==> $varray)();
+    $widened_darray = ((): varray_or_darray<int> ==> $darray)();
+    expect($widened_varray)->toEqual($varray);
+    expect($widened_darray)->toEqual($darray);
+  }
+}