Fix elaboration of HH autoimport class names when HH syntax is disabled

Jake Bailey (Hacklang) · fredemmott · commit dd720bec27cd · 2018-05-24T11:36:02.000-07:00
Summary: In Hack files, class names which are autoimported from the HH namespace are elaborated into the HH namespace. For example, Container -> \HH\Container; Traversable -> \HH\Traversable. Other class names are elaborated into the current namespace. In PHP files, we do not autoimport any classes from the HH namespace, and should not elaborate any names into that namespace. However, we currently treat any name which would be autoimported from \HH (in a Hack file) as a name in the global namespace, instead of elaborating it into the current namespace as we do with any other name. After this change, we always elaborate names into the current namespace in PHP files (unless the EnableHipHopSyntax option is set), matching HHVM's behavior for the added test case. fixes #8204 Differential Revision: D8100689
diff --git a/hphp/hack/src/parser/full_fidelity_ast.ml b/hphp/hack/src/parser/full_fidelity_ast.ml
@@ -2784,7 +2784,10 @@ let scour_comments
  * Front-end matter
 )*****************************************************************************)
 
-let elaborate_toplevel_and_std_constants ast env source_text =
+let elaborate_toplevel_and_std_constants ast (env: env) source_text =
+  let autoimport =
+    env.is_hh_file || ParserOptions.enable_hh_syntax_for_hhvm env.parser_options
+  in
   match env.elaborate_namespaces, env.saw_std_constant_redefinition with
   | true, true ->
     let elaborate_std_constants nsenv def =
@@ -2808,9 +2811,10 @@ let elaborate_toplevel_and_std_constants ast env source_text =
       end in
       visitor#on_def nsenv def in
     let parser_options = env.parser_options in
-    NS.elaborate_map_toplevel_defs parser_options ast elaborate_std_constants
+    NS.elaborate_map_toplevel_defs
+      ~autoimport parser_options ast elaborate_std_constants
   | true, false ->
-    NS.elaborate_toplevel_defs env.parser_options ast
+    NS.elaborate_toplevel_defs ~autoimport env.parser_options ast
   | _ -> ast
 
 let elaborate_halt_compiler ast env source_text  =
diff --git a/hphp/hack/src/parser/namespaces.ml b/hphp/hack/src/parser/namespaces.ml
@@ -260,8 +260,8 @@ let elaborate_id_impl ~autoimport nsenv kind (p, id) =
       (ParserOptions.auto_namespace_map nsenv.ns_popt) fully_qualified in
   was_renamed, (p, translated)
 
-let elaborate_id nsenv kind id =
-  let _, newid = elaborate_id_impl ~autoimport:true nsenv kind id in
+let elaborate_id ?(autoimport=true) nsenv kind id =
+  let _, newid = elaborate_id_impl ~autoimport nsenv kind id in
   newid
 
 (* First pass of flattening namespaces, run super early in the pipeline, right
@@ -278,22 +278,22 @@ let elaborate_id nsenv kind id =
  * allow us to fix those up during a second pass during naming.
  *)
 module ElaborateDefs = struct
-  let hint nsenv = function
+  let hint ~autoimport nsenv = function
     | p, Happly (id, args) ->
-        p, Happly (elaborate_id nsenv ElaborateClass id, args)
+        p, Happly (elaborate_id ~autoimport nsenv ElaborateClass id, args)
     | other -> other
 
-  let class_def nsenv = function
-    | ClassUse h -> ClassUse (hint nsenv h)
-    | XhpAttrUse h -> XhpAttrUse (hint nsenv h)
+  let class_def ~autoimport nsenv = function
+    | ClassUse h -> ClassUse (hint ~autoimport nsenv h)
+    | XhpAttrUse h -> XhpAttrUse (hint ~autoimport nsenv h)
     | other -> other
 
   let finish nsenv updated_nsenv stmt =
     if updated_nsenv
     then nsenv, [stmt; SetNamespaceEnv nsenv]
     else nsenv, [stmt]
 
-  let rec def map_def nsenv = function
+  let rec def ~autoimport map_def nsenv = function
     (*
       The default namespace in php is the global namespace specified by
       the empty string. In the case of an empty string, we model it as
@@ -311,7 +311,7 @@ module ElaborateDefs = struct
           | "" -> None
           | _ -> Some (parent_nsname ^ nsname) in
         let new_nsenv = {nsenv with ns_name = nsname} in
-        nsenv, SetNamespaceEnv new_nsenv :: program map_def new_nsenv prog
+        nsenv, SetNamespaceEnv new_nsenv :: program ~autoimport map_def new_nsenv prog
       end
     | NamespaceUse l -> begin
         let nsenv =
@@ -346,9 +346,9 @@ module ElaborateDefs = struct
         elaborate_defined_id nsenv ElaborateClass c.c_name in
       finish nsenv updated_nsenv @@ map_def nsenv (Class {c with
         c_name = name;
-        c_extends = List.map c.c_extends (hint nsenv);
-        c_implements = List.map c.c_implements (hint nsenv);
-        c_body = List.map c.c_body (class_def nsenv);
+        c_extends = List.map c.c_extends (hint ~autoimport nsenv);
+        c_implements = List.map c.c_implements (hint ~autoimport nsenv);
+        c_body = List.map c.c_body (class_def ~autoimport nsenv);
         c_namespace = nsenv;
       })
     | Fun f ->
@@ -386,25 +386,25 @@ module ElaborateDefs = struct
       }]
     | other -> nsenv, [map_def nsenv other]
 
-  and program f nsenv p =
+  and program ~autoimport f nsenv p =
     let _, acc =
       List.fold_left p ~init:(nsenv, []) ~f:begin fun (nsenv, acc) item ->
-        let nsenv, item = def f nsenv item in
+        let nsenv, item = def ~autoimport f nsenv item in
         nsenv, item :: acc
       end in
     List.concat (List.rev acc)
 end
 
 let noop _ x = x
 
-let elaborate_toplevel_defs_ ?(map_def = noop) popt ast  =
-  ElaborateDefs.program map_def (Namespace_env.empty popt) ast
+let elaborate_toplevel_defs_ ~autoimport ?(map_def = noop) popt ast  =
+  ElaborateDefs.program ~autoimport map_def (Namespace_env.empty popt) ast
 
-let elaborate_toplevel_defs popt ast =
-  elaborate_toplevel_defs_ popt ast
+let elaborate_toplevel_defs ~autoimport popt ast =
+  elaborate_toplevel_defs_ ~autoimport popt ast
 
-let elaborate_map_toplevel_defs popt ast map_def =
-  elaborate_toplevel_defs_ ~map_def popt ast
+let elaborate_map_toplevel_defs ~autoimport popt ast map_def =
+  elaborate_toplevel_defs_ ~autoimport ~map_def popt ast
 
 let elaborate_def nsenv def =
-  ElaborateDefs.def noop nsenv def
+  ElaborateDefs.def ~autoimport:true noop nsenv def
diff --git a/hphp/hack/src/parser/namespaces.mli b/hphp/hack/src/parser/namespaces.mli
@@ -12,7 +12,7 @@ type elaborate_kind =
   | ElaborateClass
   | ElaborateConst
 
-val elaborate_id : Namespace_env.env ->
+val elaborate_id : ?autoimport:bool -> Namespace_env.env ->
                    elaborate_kind ->
                    Ast.id ->
                    Ast.id
@@ -26,8 +26,9 @@ val elaborate_id_impl : autoimport:bool -> Namespace_env.env ->
   incur a perf hit that everybody will have to pay. For codegen purposed
   namespaces are propagated to inline declarations
   during closure conversion process *)
-val elaborate_toplevel_defs : ParserOptions.t -> Ast.program -> Ast.program
+val elaborate_toplevel_defs : autoimport:bool -> ParserOptions.t -> Ast.program -> Ast.program
 val elaborate_map_toplevel_defs :
+  autoimport:bool ->
   ParserOptions.t ->
   Ast.program ->
   (Namespace_env.env -> Ast.def -> Ast.def) ->
diff --git a/hphp/hack/src/parser/parser_hack.ml b/hphp/hack/src/parser/parser_hack.ml
@@ -481,8 +481,10 @@ let rec program
     Fixmes.HH_FIXMES.add env.file fixmes;
     Option.iter (List.last !(env.errors)) Errors.parsing_error
   end;
+  let autoimport =
+    is_hh_file || ParserOptions.enable_hh_syntax_for_hhvm env.popt in
   let ast = if elaborate_namespaces
-    then Namespaces.elaborate_toplevel_defs env.popt ast
+    then Namespaces.elaborate_toplevel_defs ~autoimport env.popt ast
     else ast in
   {file_mode; is_hh_file; comments; ast; content}
 
diff --git a/hphp/test/slow/namespace/autoimport.php b/hphp/test/slow/namespace/autoimport.php
@@ -0,0 +1,20 @@
+<?php
+
+namespace AutoimportTest;
+
+include 'autoimport_defs.inc';
+
+class ContainerExt extends Container {}
+class TraversableExt extends Traversable {}
+
+$a = new Container;
+var_dump(get_class($a));
+
+$a = new ContainerExt;
+var_dump(get_class($a));
+
+$a = new Traversable;
+var_dump(get_class($a));
+
+$a = new TraversableExt;
+var_dump(get_class($a));
diff --git a/hphp/test/slow/namespace/autoimport.php.expectf b/hphp/test/slow/namespace/autoimport.php.expectf
@@ -0,0 +1,4 @@
+string(24) "AutoimportTest\Container"
+string(27) "AutoimportTest\ContainerExt"
+string(26) "AutoimportTest\Traversable"
+string(29) "AutoimportTest\TraversableExt"
diff --git a/hphp/test/slow/namespace/autoimport_defs.inc b/hphp/test/slow/namespace/autoimport_defs.inc
@@ -0,0 +1,6 @@
+<?php
+
+namespace AutoimportTest;
+
+class Container {}
+class Traversable {}
