From 071b53136ad2c447b8c4f2350185c4fc2c70b274 Mon Sep 17 00:00:00 2001
From: Simon Krajewski <simon@haxe.org>
Date: Tue, 26 Nov 2024 13:28:36 +0100
Subject: [PATCH] disallow defining types into existing modules

---
 src/typing/macroContext.ml                    | 24 +++++----
 tests/misc/projects/Issue4160/compile.hxml    |  2 -
 .../projects/Issue4160/compile.hxml.stderr    |  1 -
 tests/misc/projects/Issue4160/test/Main.hx    | 51 -------------------
 tests/misc/projects/Issue6006/Macro.hx        |  2 +-
 5 files changed, 14 insertions(+), 66 deletions(-)
 delete mode 100644 tests/misc/projects/Issue4160/compile.hxml
 delete mode 100644 tests/misc/projects/Issue4160/compile.hxml.stderr
 delete mode 100644 tests/misc/projects/Issue4160/test/Main.hx

diff --git a/src/typing/macroContext.ml b/src/typing/macroContext.ml
index 7b0fde048c0..5583d26e4b3 100644
--- a/src/typing/macroContext.ml
+++ b/src/typing/macroContext.ml
@@ -492,6 +492,14 @@ let make_macro_api ctx mctx p =
 				()
 		);
 		MacroApi.define_module = (fun m types imports usings ->
+			let mpath = Ast.parse_path m in
+			if ctx.com.module_lut#mem mpath then begin
+				let m = ctx.com.module_lut#find mpath in
+				let pos = { pfile = (Path.UniqueKey.lazy_path m.m_extra.m_file); pmin = 0; pmax = 0 } in
+				raise_typing_error_ext (make_error ~sub:[
+					make_error ~depth:1 (Custom "Previously defined here") pos
+				] (Custom (Printf.sprintf "Cannot redefine module %s" (s_type_path mpath))) p);
+			end;
 			let types = List.map (fun v ->
 				let _, tdef, pos = (try Interp.decode_type_def v with MacroApi.Invalid_expr -> Interp.exc_string "Invalid type definition") in
 				tdef, pos
@@ -503,17 +511,11 @@ let make_macro_api ctx mctx p =
 				EUsing (List.map (fun s -> s,null_pos) sl),pos
 			) usings in
 			let types = imports @ usings @ types in
-			let mpath = Ast.parse_path m in
-			begin try
-				let m = ctx.com.module_lut#find mpath in
-				ignore(TypeloadModule.type_types_into_module ctx.com ctx.g m types pos)
-			with Not_found ->
-				let mnew = TypeloadModule.type_module ctx.com ctx.g mpath (ctx.com.file_keys#generate_virtual ctx.com.compilation_step) types pos in
-				mnew.m_extra.m_kind <- MFake;
-				add_dependency mnew ctx.m.curmod MDepFromMacro;
-				add_dependency ctx.m.curmod mnew MDepFromMacroDefine;
-				ctx.com.module_nonexistent_lut#clear;
-			end
+			let mnew = TypeloadModule.type_module ctx.com ctx.g mpath (ctx.com.file_keys#generate_virtual ctx.com.compilation_step) types pos in
+			mnew.m_extra.m_kind <- MFake;
+			add_dependency mnew ctx.m.curmod MDepFromMacro;
+			add_dependency ctx.m.curmod mnew MDepFromMacroDefine;
+			ctx.com.module_nonexistent_lut#clear;
 		);
 		MacroApi.module_dependency = (fun mpath file ->
 			let m = typing_timer ctx false (fun ctx ->
diff --git a/tests/misc/projects/Issue4160/compile.hxml b/tests/misc/projects/Issue4160/compile.hxml
deleted file mode 100644
index aae7872d734..00000000000
--- a/tests/misc/projects/Issue4160/compile.hxml
+++ /dev/null
@@ -1,2 +0,0 @@
---main test.Main
---interp
\ No newline at end of file
diff --git a/tests/misc/projects/Issue4160/compile.hxml.stderr b/tests/misc/projects/Issue4160/compile.hxml.stderr
deleted file mode 100644
index 19102815663..00000000000
--- a/tests/misc/projects/Issue4160/compile.hxml.stderr
+++ /dev/null
@@ -1 +0,0 @@
-foo
\ No newline at end of file
diff --git a/tests/misc/projects/Issue4160/test/Main.hx b/tests/misc/projects/Issue4160/test/Main.hx
deleted file mode 100644
index af6c0542e0b..00000000000
--- a/tests/misc/projects/Issue4160/test/Main.hx
+++ /dev/null
@@ -1,51 +0,0 @@
-package test;
-
-import haxe.macro.Context;
-import haxe.macro.Expr;
-
-private class Bar {
-	public function new() { }
-	public function getValue() {
-		return "foo";
-	}
-}
-
-class Main
-{
-    static function main()
-    {
-        defineFooExtendsBarInLocalModule();
-		#if !macro
-		var foo = new Foo();
-		Sys.stderr().writeString(foo.getValue());
-		#end
-    }
-
-    macro static function defineFooExtendsBarInLocalModule(?e)
-    {
-        var infos = Context.getPosInfos(Context.currentPos());
-        var position = Context.makePosition({min:0, max:0, file:infos.file});
-
-        var superTypePath:TypePath =
-        {
-            pack: [],
-            name: "Bar",
-            sub: null
-        }
-
-        var kind:TypeDefKind = TypeDefKind.TDClass(superTypePath);
-
-        var Foo:TypeDefinition =
-        {
-            name: "Foo",
-            pack: ["test"],
-            pos: position,
-            kind: kind,
-            fields: []
-        }
-
-        Context.defineModule(Context.getLocalModule(), [Foo]);
-
-        return e;
-    }
-}
\ No newline at end of file
diff --git a/tests/misc/projects/Issue6006/Macro.hx b/tests/misc/projects/Issue6006/Macro.hx
index 4429e6f839f..c9f6745a189 100644
--- a/tests/misc/projects/Issue6006/Macro.hx
+++ b/tests/misc/projects/Issue6006/Macro.hx
@@ -4,7 +4,7 @@ import haxe.macro.Expr;
 class Macro {
     static function build() {
         var pos = Context.currentPos();
-        Context.defineModule(Context.getLocalModule(), [{
+        Context.defineModule("A", [{
             pos: pos,
             pack: [],
             name: "A",