Add HackBuilderKeys::lambda() and HackBuilderValues::lambda()

More convenient than subclassing for one-offs.

fixes #31

Author: fredemmott

src/key-value-render/HackBuilderClassnameRenderer.php

@@ -11,7 +11,7 @@
 
 namespace Facebook\HackCodegen;
 
-final class HackBuilderClassnameRender
+final class HackBuilderClassnameRenderer
 implements IHackBuilderKeyRenderer<string>, IHackBuilderValueRenderer<string> {
   final public function render(
     IHackCodegenConfig $_,

src/key-value-render/HackBuilderKeyExportRenderer.php

@@ -11,7 +11,7 @@
 
 namespace Facebook\HackCodegen;
 
-final class HackBuilderKeyExportRender
+final class HackBuilderKeyExportRenderer
 implements IHackBuilderKeyRenderer<arraykey> {
   final public function render(
     IHackCodegenConfig $_,

src/key-value-render/HackBuilderKeyLambdaRenderer.php

@@ -0,0 +1,28 @@
+<?hh // strict
+/*
+ *  Copyright (c) 2015, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+namespace Facebook\HackCodegen;
+
+final class HackBuilderKeyLambdaRenderer<T as arraykey>
+implements IHackBuilderKeyRenderer<T> {
+  public function __construct(
+    private (function(IHackCodegenConfig, T):string) $callback,
+  ) {
+  }
+
+  final public function render(
+    IHackCodegenConfig $config,
+    T $value,
+  ): string {
+    $callback = $this->callback;
+    return $callback($config, $value);
+  }
+}

src/HackBuilderKeys.php renamed to src/key-value-render/HackBuilderKeys.php

@@ -15,18 +15,27 @@
    * passing a constant such as MyEnum::Value
    */
   public static function literal(): IHackBuilderKeyRenderer<string> {
-    return new HackBuilderLiteralRender();
+    return new HackBuilderLiteralRenderer();
   }
 
   /* The key will be exported to be rendered according the type.  E.g. an int
    * will be rendered without changes but a string will be rendered with quotes.
    */
   public static function export(): IHackBuilderKeyRenderer<arraykey> {
-    return new HackBuilderKeyExportRender();
+    return new HackBuilderKeyExportRenderer();
   }
 
-  /* The key will be renderered as a classname<T> */
+  /** The key will be renderered as a classname<T> */
   public static function classname(): IHackBuilderKeyRenderer<string> {
-    return new HackBuilderClassnameRender();
+    return new HackBuilderClassnameRenderer();
+  }
+
+  /**
+   * The key will be rendered with the specified lambda
+   */
+  public static function lambda<T as arraykey>(
+    (function(IHackCodegenConfig, T): string) $render,
+  ): IHackBuilderKeyRenderer<T> {
+    return new HackBuilderKeyLambdaRenderer($render);
   }
 }

src/key-value-render/HackBuilderLiteralRenderer.php

@@ -11,7 +11,7 @@
 
 namespace Facebook\HackCodegen;
 
-final class HackBuilderLiteralRender
+final class HackBuilderLiteralRenderer
 implements IHackBuilderKeyRenderer<string>, IHackBuilderValueRenderer<string> {
   final public function render(
     IHackCodegenConfig $_,

src/key-value-render/HackBuilderValueExportRenderer.php

@@ -11,7 +11,7 @@
 
 namespace Facebook\HackCodegen;
 
-final class HackBuilderValueExportRender
+final class HackBuilderValueExportRenderer
 implements IHackBuilderValueRenderer<mixed> {
   final public function render(
     IHackCodegenConfig $_,

src/key-value-render/HackBuilderValueLambdaRenderer.php

@@ -0,0 +1,28 @@
+<?hh // strict
+/*
+ *  Copyright (c) 2015, Facebook, Inc.
+ *  All rights reserved.
+ *
+ *  This source code is licensed under the BSD-style license found in the
+ *  LICENSE file in the root directory of this source tree. An additional grant
+ *  of patent rights can be found in the PATENTS file in the same directory.
+ *
+ */
+
+namespace Facebook\HackCodegen;
+
+final class HackBuilderValueLambdaRenderer<T>
+implements IHackBuilderValueRenderer<T> {
+  public function __construct(
+    private (function(IHackCodegenConfig, T):string) $callback,
+  ) {
+  }
+
+  final public function render(
+    IHackCodegenConfig $config,
+    T $value,
+  ): string {
+    $callback = $this->callback;
+    return $callback($config, $value);
+  }
+}

src/HackBuilderValues.php renamed to src/key-value-render/HackBuilderValues.php

@@ -14,13 +14,13 @@
   // The value will be used literally, which is useful for example when
   // passing a constant such as MyEnum::Value
   public static function literal(): IHackBuilderValueRenderer<string> {
-    return new HackBuilderLiteralRender();
+    return new HackBuilderLiteralRenderer();
   }
 
   // The value will be exported to be rendered according the type.  E.g. an int
   // will be rendered without changes but a string will be rendered with quotes.
   public static function export(): IHackBuilderValueRenderer<mixed> {
-    return new HackBuilderValueExportRender();
+    return new HackBuilderValueExportRenderer();
   }
 
   public static function valueArray<Tv>(
@@ -95,6 +95,15 @@ public static function shapeWithPerKeyRendering(
 
   /* The key will be renderered as a classname<T> */
   public static function classname(): IHackBuilderValueRenderer<string> {
-    return new HackBuilderClassnameRender();
+    return new HackBuilderClassnameRenderer();
+  }
+
+  /**
+   * The value will be rendered with the specified lambda
+   */
+  public static function lambda<T>(
+    (function(IHackCodegenConfig, T): string) $render,
+  ): IHackBuilderValueRenderer<T> {
+    return new HackBuilderValueLambdaRenderer($render);
   }
 }

test/HackBuilderTest.codegen

@@ -63,6 +63,10 @@ if ($value <= 0) {
   return 2;
 }
 
+!@#$%codegentest:testLambdaMap
+Map {
+  'key:foo' => 'value:bar',
+}
 !@#$%codegentest:testLiteralMap
 Map {
   MY_ENUM::A => ANOTHER_ENUM::A,

test/HackBuilderTest.php

@@ -377,6 +377,18 @@ public function testClassnameMap(): void {
       );
     $this->assertUnchanged($body->getCode());
   }
+
+  public function testLambdaMap(): void {
+    $body = $this->getHackBuilder()
+      ->addValue(
+        Map { 'foo' => 'bar' },
+        HackBuilderValues::map(
+          HackBuilderKeys::lambda(($_config, $v) ==> "'key:$v'"),
+          HackBuilderValues::lambda(($_config, $v) ==> "'value:$v'",)
+        ),
+      );
+    $this->assertUnchanged($body->getCode());
+  }
 }
 
 final class TestAnotherCodegenConfig implements IHackCodegenConfig {