feat(compiler)!: access modifiers for classes, structs, interfaces, e…

…nums (winglang#4591)

Wing now supports declaring classes, structs, interfaces, and enums as public using the `pub` access modifier. The default access of all types is now private.

This PR also fixes a bug where you could not `bring` modules under the same alias in different files.

Closes winglang#4294
Closes winglang#4415
Closes winglang#2763

BREAKING CHANGE: All types are private by default. To make a class, struct, or other declaration accessible to other files, prefix it with the `pub` access modifier.

## Checklist

- [x] Title matches [Winglang's style guide](https://www.winglang.io/contributing/start-here/pull_requests#how-are-pull-request-titles-formatted)
- [x] Description explains motivation and solution
- [x] Tests added (always)
- [x] Docs updated (only required for features)
- [ ] Added `pr/e2e-full` label if this feature requires end-to-end testing

*By submitting this pull request, I confirm that my contribution is made under the terms of the [Wing Cloud Contribution License](https://github.com/winglang/wing/blob/main/CONTRIBUTION_LICENSE.md)*.

docs/docs/03-language-reference.md

@@ -1146,7 +1146,6 @@ The following features are not yet implemented, but we are planning to add them
 
 ### 1.14 Roadmap
 
-* Module type visibility (exports/`pub` types) is not implemented yet - see https://github.com/winglang/wing/issues/130 to track.
 * `internal` access modifier is not yet implemented - see https://github.com/winglang/wing/issues/4156 to track.
 
 ## 2. Statements

examples/tests/invalid/access_private_apis.test.w

@@ -0,0 +1,18 @@
+bring "./subdir2" as subdir2;
+
+new subdir2.MyPrivateClass();
+// error: Class "MyPrivateClass" is private
+
+new subdir2.inner.MyOtherPrivateClass();
+// error: Class "MyOtherPrivateClass" is private
+// TODO: error: namespace "inner" is private
+// (because it has no public API elements)
+
+class A impl subdir2.MyPrivateInterface {}
+// error: Interface "MyPrivateInterface" is private
+
+let s = subdir2.MyPrivateStruct {};
+// error: Struct "MyPrivateStruct" is private
+
+let e = subdir2.MyPrivateEnum.A;
+// error: Enum "MyPrivateEnum" is private

examples/tests/invalid/file_with_variables.w

@@ -6,7 +6,7 @@ let x = 5;
 let y = ["hello", "world"];
 let z = new cloud.Bucket();
 
-class Bar {
+pub class Bar {
   x: num;
 }
 

examples/tests/invalid/protected_access_modifiers.test.w

@@ -0,0 +1,11 @@
+protected struct MyStruct {}
+// ^ Structs must be public or private
+
+protected class MyClass {}
+// ^ Classes must be public or private
+
+protected interface MyInterface {}
+// ^ Interfaces must be public or private
+
+protected enum MyEnum {}
+// ^ Enums must be public or private

examples/tests/invalid/subdir/inner/foo1.w

@@ -1 +1 @@
-class Foo {}
+pub class Foo {}

examples/tests/invalid/subdir/inner/foo2.w

@@ -1 +1 @@
-class Foo {}
+pub class Foo {}

examples/tests/invalid/subdir2/file.w

@@ -0,0 +1,7 @@
+class MyPrivateClass {}
+
+struct MyPrivateStruct {}
+
+enum MyPrivateEnum { A, B }
+
+interface MyPrivateInterface {}

examples/tests/invalid/subdir2/inner/blah.w

@@ -0,0 +1 @@
+class MyOtherPrivateClass {}

examples/tests/sdk_tests/state/my-service.w

@@ -2,7 +2,7 @@ bring sim;
 bring cloud;
 bring util;
 
-class MyService {
+pub class MyService {
   pub state: sim.State;
   startTimeKey: str;
   pub startTime: str;

examples/tests/valid/assertions.w

@@ -3,7 +3,7 @@
 // - api_cors_default.test.w
 // - website_with_api.test.w
 
-inflight class Assert {
+pub inflight class Assert {
   pub static equalStr(a: str, b: str): bool {
     try {
       assert(a == b);
@@ -29,4 +29,4 @@ inflight class Assert {
       throw("expected: ${b} got: ${a}");
     }
   }
-}
+}

examples/tests/valid/baz.w

@@ -1,7 +1,7 @@
 // used by:
 // - bring_local_normalization.test.w
 
-class Baz {
+pub class Baz {
   pub static baz(): str {
     return "baz";
   }

examples/tests/valid/store.w

@@ -5,9 +5,9 @@ bring "./subdir/empty.w" as file3;
 bring math;
 bring cloud;
 
-class Util {}
+pub class Util {}
 
-class Store {
+pub class Store {
   b: cloud.Bucket;
   init() {
     this.b = new cloud.Bucket();
@@ -21,17 +21,17 @@ class Store {
   }
 }
 
-enum Color {
+pub enum Color {
   RED,
   GREEN,
   BLUE,
 }
 
-struct Point {
+pub struct Point {
   x: num;
   y: num;
 }
 
-interface Shape {
+pub interface Shape {
   area(): num;
 }

examples/tests/valid/subdir/bar.w

@@ -1,6 +1,6 @@
 // used by bring_local_normalization.w
 
-class Bar {
+pub class Bar {
   pub static bar(): str {
     return "bar";
   }

examples/tests/valid/subdir/foo.w

@@ -3,7 +3,7 @@
 bring "./bar.w" as bar;
 bring "../baz.w" as baz;
 
-class Foo {
+pub class Foo {
   pub static foo(): str {
     return "foo";
   }

examples/tests/valid/subdir/structs.w

@@ -1,7 +1,7 @@
-struct MyStruct {
+pub struct MyStruct {
   val: num;
 }
 
-struct MyOtherStruct {
+pub struct MyOtherStruct {
   data: MyStruct;
-}
+}

examples/tests/valid/subdir/structs_2.w

@@ -1,15 +1,15 @@
-struct MyStruct {
+pub struct MyStruct {
   val: str;
 }
 
-struct SomeStruct {
+pub struct SomeStruct {
   foo: str;
 }
 
-class UsesStructInImportedFile {
+pub class UsesStructInImportedFile {
   someStruct: SomeStruct;
 
   init() {
     this.someStruct = SomeStruct.fromJson({foo: "123"});
   }
-}
+}

examples/tests/valid/subdir/subfile.w

@@ -1,5 +1,5 @@
 bring math;
 
-class Q {
+pub class Q {
   extern "./util.js" static inflight greet(name: str): str;
 }

examples/tests/valid/subdir2/file1.w

@@ -1,6 +1,7 @@
 bring "./inner" as blah; // an alias that is not "inner"
+bring util;
 
-class Foo {
+pub class Foo {
   pub foo(): str {
     return "foo";
   }

examples/tests/valid/subdir2/file2.w

@@ -1,5 +1,11 @@
-class Bar {
+bring util;
+
+pub class Bar {
   pub bar(): str {
     return "bar";
   }
 }
+
+// this file's sibling, file1.w, also has a class "Foo"
+// but this is okay since it's private
+class Foo {}

examples/tests/valid/subdir2/inner/widget.w

@@ -1,4 +1,4 @@
-class Widget {
+pub class Widget {
   pub compute(): num {
     return 42;
   }

examples/wing-fixture/enums.w

@@ -1,4 +1,4 @@
-enum FavoriteNumbers {
+pub enum FavoriteNumbers {
   SEVEN,
   FORTY_TWO,
 }

examples/wing-fixture/store.w

@@ -1,7 +1,7 @@
 bring cloud;
 bring "./subdir/util.w" as myutil;
 
-class Store {
+pub class Store {
   data: cloud.Bucket;
   init() {
     this.data = new cloud.Bucket();

examples/wing-fixture/subdir/util.w

@@ -1,4 +1,4 @@
-class Util {
+pub class Util {
   pub static inflight double(msg: str): str {
     return "${msg}${msg}";
   }

libs/tree-sitter-wing/grammar.js

@@ -105,7 +105,6 @@ module.exports = grammar({
         $.variable_assignment_statement,
         $.return_statement,
         $.class_definition,
-        $.resource_definition,
         $.interface_definition,
         $.for_in_loop,
         $.while_statement,
@@ -131,6 +130,7 @@ module.exports = grammar({
 
     struct_definition: ($) =>
       seq(
+        optional(field("access_modifier", $.access_modifier)),
         "struct",
         field("name", $.identifier),
         optional(seq("extends", commaSep(field("extends", $.custom_type)))),
@@ -141,6 +141,7 @@ module.exports = grammar({
 
     enum_definition: ($) =>
       seq(
+        optional(field("access_modifier", $.access_modifier)),
         "enum",
         field("enum_name", $.identifier),
         braced(commaSep(alias($.identifier, $.enum_field)))
@@ -185,7 +186,8 @@ module.exports = grammar({
     // Classes
     class_definition: ($) =>
       seq(
-        $.inflight_specifier,
+        optional(field("access_modifier", $.access_modifier)),
+        optional(field("phase_modifier", $.inflight_specifier)),
         "class",
         field("name", $.identifier),
         optional(seq("extends", field("parent", $.custom_type))),
@@ -217,28 +219,9 @@ module.exports = grammar({
         $._semicolon
       ),
 
-    resource_definition: ($) =>
-      seq(
-        "class",
-        field("name", $.identifier),
-        optional(seq("extends", field("parent", $.custom_type))),
-        optional(seq("impl", field("implements", commaSep1($.custom_type)))),
-        field("implementation", $.resource_implementation)
-      ),
-    resource_implementation: ($) =>
-      braced(
-        repeat(
-          choice(
-            $.initializer,
-            $.method_definition,
-            $.inflight_method_definition,
-            $.class_field
-          )
-        )
-      ),
-
     interface_definition: ($) =>
       seq(
+        optional(field("access_modifier", $.access_modifier)),
         "interface",
         field("name", $.identifier),
         optional(seq("extends", field("extends", commaSep1($.custom_type)))),

libs/tree-sitter-wing/test/corpus/statements/class_and_resource.txt

@@ -16,7 +16,7 @@ inflight class A {
 
 (source
   (class_definition
-    (inflight_specifier)
+    phase_modifier: (inflight_specifier)
     name: (identifier)
     implementation: (class_implementation
       (initializer
@@ -59,7 +59,7 @@ inflight class A extends B {}
 
 (source
   (class_definition
-    (inflight_specifier)
+    phase_modifier: (inflight_specifier)
     name: (identifier)
     parent: (custom_type
       object: (type_identifier))
@@ -90,9 +90,9 @@ class A {
 --------------------------------------------------------------------------------
 
 (source
-  (resource_definition
+  (class_definition
     name: (identifier)
-    implementation: (resource_implementation
+    implementation: (class_implementation
       (initializer
         parameter_list: (parameter_list)
         block: (block))
@@ -177,15 +177,15 @@ class A extends B impl C, D {}
 --------------------------------------------------------------------------------
 
 (source
-  (resource_definition
+  (class_definition
     name: (identifier)
     parent: (custom_type
       object: (type_identifier))
     implements: (custom_type
       object: (type_identifier))
     implements: (custom_type
       object: (type_identifier))
-    implementation: (resource_implementation)))
+    implementation: (class_implementation)))
 
 ================================================================================
 Interface definition

libs/wingc/src/ast.rs

@@ -298,7 +298,7 @@ pub struct FunctionDefinition {
 	/// Whether this function is static or not. In case of a closure, this is always true.
 	pub is_static: bool,
 	/// Function's access modifier. In case of a closure, this is always public.
-	pub access_modifier: AccessModifier,
+	pub access: AccessModifier,
 	pub span: WingSpan,
 }
 
@@ -361,6 +361,7 @@ pub struct Class {
 	pub parent: Option<UserDefinedType>, // base class (the expression is a reference to a user defined type)
 	pub implements: Vec<UserDefinedType>,
 	pub phase: Phase,
+	pub access: AccessModifier,
 }
 
 impl Class {
@@ -422,6 +423,7 @@ pub struct Interface {
 	pub name: Symbol,
 	pub methods: Vec<(Symbol, FunctionSignature)>,
 	pub extends: Vec<UserDefinedType>,
+	pub access: AccessModifier,
 }
 
 #[derive(Debug)]
@@ -501,10 +503,12 @@ pub enum StmtKind {
 		name: Symbol,
 		extends: Vec<UserDefinedType>,
 		fields: Vec<StructField>,
+		access: AccessModifier,
 	},
 	Enum {
 		name: Symbol,
 		values: IndexSet<Symbol>,
+		access: AccessModifier,
 	},
 	TryCatch {
 		try_statements: Scope,
@@ -527,7 +531,7 @@ pub struct ClassField {
 	pub reassignable: bool,
 	pub phase: Phase,
 	pub is_static: bool,
-	pub access_modifier: AccessModifier,
+	pub access: AccessModifier,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq)]