Typechecker support for throwing and catching throwables and errors

fredemmott · fredemmott · commit 9235b1f388d7 · 2018-03-22T14:01:38.000-07:00
Summary: PHP7 mode is default now, so these are thrown. fixes #8153 Reviewed By: vassilmladenov Differential Revision: D7304627 fbshipit-source-id: 390e5a8bb35a5bdd2282b9d520fd105ace26a58a
diff --git a/hphp/hack/src/naming/naming_special_names.ml b/hphp/hack/src/naming/naming_special_names.ml
@@ -28,7 +28,7 @@ module Classes = struct
 
   let cHH_BuiltinEnum = "\\HH\\BuiltinEnum"
 
-  let cException = "\\Exception"
+  let cThrowable= "\\Throwable"
   let cStdClass = "\\stdClass"
   let cDateTime = "\\DateTime"
 
diff --git a/hphp/hack/src/typing/typing.ml b/hphp/hack/src/typing/typing.ml
@@ -2816,7 +2816,7 @@ and uninstantiable_error reason_pos cid c_tc_pos c_name c_usage_pos c_ty =
   Errors.uninstantiable_class c_usage_pos c_tc_pos c_name reason_msgl
 
 and exception_ty pos env ty =
-  let exn_ty = Reason.Rthrow pos, Tclass ((pos, SN.Classes.cException), []) in
+  let exn_ty = Reason.Rthrow pos, Tclass ((pos, SN.Classes.cThrowable), []) in
   Type.sub_type pos (Reason.URthrow) env ty exn_ty
 
 and shape_field_pos = function
diff --git a/hphp/hack/test/typecheck/catch_non_exception.php.exp b/hphp/hack/test/typecheck/catch_non_exception.php.exp
@@ -1,6 +1,6 @@
 File "catch_non_exception.php", line 7, characters 12-23:
 Invalid exception (Typing[4110])
 File "catch_non_exception.php", line 7, characters 12-23:
-This is an object of type Exception because it is used as an exception
+This is an object of type Throwable because it is used as an exception
 File "catch_non_exception.php", line 7, characters 12-23:
 It is incompatible with an object of type NonException
diff --git a/hphp/hack/test/typecheck/php7_throwables.php b/hphp/hack/test/typecheck/php7_throwables.php
@@ -0,0 +1,51 @@
+<?hh // strict
+
+
+class Foo implements Throwable {
+  public function getMessage(): string {
+    return __FUNCTION__;
+  }
+  public function getCode(): int {
+    return __LINE__;
+  }
+  public function getLine(): int {
+    return __LINE__;
+  }
+  public function getFile(): string {
+    return __FILE__;
+  }
+  public function getTrace(): array<mixed> {
+    return [];
+  }
+  public function getTraceAsString(): string {
+    return 'nope';
+  }
+  public function getPrevious(): ?Throwable {
+    return null;
+  }
+  public function __toString(): string {
+    return __FUNCTION__;
+  }
+}
+
+function catches(): void {
+  try {
+  } catch (Exception $_) {
+  }
+  try {
+  } catch (Throwable $_) {
+  }
+  try {
+  } catch (Error $_) {
+  }
+  try {
+  } catch (Foo $_) {
+  }
+}
+
+function throws(): void {
+  throw new Exception();
+  throw new Error();
+  throw new TypeError();
+  throw new Foo();
+}
diff --git a/hphp/hack/test/typecheck/php7_throwables.php.exp b/hphp/hack/test/typecheck/php7_throwables.php.exp
@@ -0,0 +1 @@
+No errors
diff --git a/hphp/hack/test/typecheck/throw_non_exception.php.exp b/hphp/hack/test/typecheck/throw_non_exception.php.exp
@@ -1,6 +1,6 @@
 File "throw_non_exception.php", line 6, characters 9-26:
 Invalid exception (Typing[4110])
 File "throw_non_exception.php", line 6, characters 9-26:
-This is an object of type Exception because it is used as an exception
+This is an object of type Throwable because it is used as an exception
 File "throw_non_exception.php", line 6, characters 9-26:
 It is incompatible with an object of type NonException
