Merge pull request #67 from slackhq/ih_improve_UntypedBuilder_type_inference

Generate "Union" Types for anyOf Constraint

Author: ianhoffman

Makefile

@@ -19,7 +19,7 @@ lint:
 	docker run -v `pwd`:/app -it slack/hack-json-schema ./vendor/bin/hhast-lint
 
 format:
-	docker run -v `pwd`:/app -it slack/hack-json-schema find {src,tests} -type f -name "*.hack" -o -name "*.php" -exec hackfmt -i {} \;
+	docker run -v `pwd`:/app -it slack/hack-json-schema find {src,tests} -type f \( -name "*.hack" -o -name "*.php" \)  -exec hackfmt -i {} \;
 
 typecheck:
 	docker run -v `pwd`:/app -it slack/hack-json-schema /bin/bash -c './vendor/bin/hh-autoload && hh_server --check .'

src/Codegen/Codegen.php

@@ -263,6 +263,7 @@ public function build(): this {
       $this->file->addBeforeType(
         $this->getHackCodegenFactory()->codegenType($this->getType())->setType($this->builder->getType()),
       );
+      Typing\TypeSystem::registerAlias($this->getType(), $this->builder->getTypeInfo());
     }
 
     $this->class = $this->class
@@ -329,6 +330,16 @@ public function isArrayKeyType(): bool {
     return $this->builder->isArrayKeyType();
   }
 
+  public function getTypeInfo(): Typing\Type {
+    // If we're referencing a different schema, always generate an alias.
+    // Otherwise, simply delegate to the builder, which may or may not
+    // build an alias itself (e.g., in the case of ObjectBuilder).
+    if ($this->builder->isUniqueRef()) {
+      return Typing\TypeSystem::alias($this->builder->getType());
+    }
+    return $this->builder->getTypeInfo();
+  }
+
   public function setSuffix(string $_suffix): void {
   }
 }

src/Codegen/Constraints/ArrayBuilder.php

@@ -268,4 +268,18 @@ private function determineHackArrayType(): void {
       $this->hackArrayType = HackArrayType::KEYSET;
     }
   }
+
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    if ($this->singleItemSchemaBuilder) {
+      $inner = $this->singleItemSchemaBuilder->getTypeInfo();
+    } else {
+      $inner = Typing\TypeSystem::mixed();
+    }
+    if ($this->hackArrayType === HackArrayType::KEYSET) {
+      return Typing\TypeSystem::keyset($inner);
+    } else {
+      return Typing\TypeSystem::vec($inner);
+    }
+  }
 }

src/Codegen/Constraints/BooleanBuilder.php

@@ -51,4 +51,8 @@ protected function getCheckMethod(): CodegenMethod {
       ->setReturnType($this->getType());
   }
 
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    return Typing\TypeSystem::bool();
+  }
 }

src/Codegen/Constraints/IBuilder.php

@@ -8,4 +8,5 @@ public function getType(): string;
   public function isArrayKeyType(): bool;
   public function build(): this;
   public function setSuffix(string $suffix): void;
+  public function getTypeInfo(): Typing\Type;
 }

src/Codegen/Constraints/NullBuilder.php

@@ -44,4 +44,8 @@ public function getType(): string {
     return 'null';
   }
 
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    return Typing\TypeSystem::null();
+  }
 }

src/Codegen/Constraints/NumberBuilder.php

@@ -120,4 +120,15 @@ public function getType(): string {
     return 'num';
   }
 
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    if ($this->getType() === 'int') {
+      return Typing\TypeSystem::int();
+    } else if ($this->getType() === 'num') {
+      return Typing\TypeSystem::num();
+    } else {
+      // TODO: Handle hackEnum
+      return Typing\TypeSystem::nonnull();
+    }
+  }
 }

src/Codegen/Constraints/ObjectBuilder.php

@@ -109,6 +109,8 @@ public function build(): this {
 
     // Generate a type based on the specified properties
     $type = $this->codegenType($property_classes, $pattern_properties_classes);
+    // TODO: Register objects as shapes or dicts
+    Typing\TypeSystem::registerAlias($this->getType(), Typing\TypeSystem::nonnull());
     $this->ctx->getFile()->addBeforeType($type);
     return $this;
   }
@@ -560,4 +562,8 @@ private function codegenType(
     }
   }
 
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    return Typing\TypeSystem::alias($this->getType());
+  }
 }

src/Codegen/Constraints/SchemaBuilder.php

@@ -172,6 +172,10 @@ public function getResolvedContext(): Context {
     return $this->resolvedContext;
   }
 
+  public function getTypeInfo(): Typing\Type {
+    return $this->builder->getTypeInfo();
+  }
+
   public function setSuffix(string $suffix): void {
     $this->builder->setSuffix($suffix);
   }

src/Codegen/Constraints/StringBuilder.php

@@ -151,4 +151,13 @@ public function getType(): string {
 
     return 'string';
   }
+
+  <<__Override>>
+  public function getTypeInfo(): Typing\Type {
+    if ($this->getType() === 'string') {
+      return Typing\TypeSystem::string();
+    }
+    // TODO: Type resolution for hackEnum
+    return Typing\TypeSystem::nonnull();
+  }
 }