fix export of JSX components inside module with regular functions

Author: tsnobip

compiler/syntax/src/jsx_common.ml

@@ -7,6 +7,12 @@ type jsx_config = {
   mutable nested_modules: string list;
   mutable has_component: bool;
   mutable hoisted_structure_items: structure_item list;
+  (* Nesting depth of [structure] calls while rewriting one implementation.
+     Used so we only clear/append hoisted items at the true file root — not for
+     nested [Pmod_structure] reached from expression traversal (e.g. via
+     [module_expr]), which would otherwise see [nested_modules = []] and wipe
+     hoisted bindings added for earlier structure items. *)
+  mutable structure_depth: int;
 }
 
 (* Helper method to look up the [@react.component] attribute *)

compiler/syntax/src/jsx_ppx.ml

@@ -117,7 +117,8 @@ let get_mapper ~config =
   in
   let structure mapper items =
     let old_config = save_config () in
-    let is_top_level = config.nested_modules = [] in
+    let is_top_level = config.structure_depth = 0 in
+    config.structure_depth <- config.structure_depth + 1;
     config.has_component <- false;
     if is_top_level then config.hoisted_structure_items <- [];
     let result =
@@ -136,6 +137,7 @@ let get_mapper ~config =
         result @ List.rev config.hoisted_structure_items
       else result
     in
+    config.structure_depth <- config.structure_depth - 1;
     restore_config old_config;
     result
   in
@@ -151,6 +153,7 @@ let rewrite_implementation ~jsx_version ~jsx_module (code : Parsetree.structure)
       nested_modules = [];
       has_component = false;
       hoisted_structure_items = [];
+      structure_depth = 0;
     }
   in
   let mapper = get_mapper ~config in
@@ -165,6 +168,7 @@ let rewrite_signature ~jsx_version ~jsx_module (code : Parsetree.signature) :
       nested_modules = [];
       has_component = false;
       hoisted_structure_items = [];
+      structure_depth = 0;
     }
   in
   let mapper = get_mapper ~config in

tests/build_tests/react_ppx/src/gpr_3695_test.res.js

@@ -31,6 +31,27 @@ assert.match(
 );
 
 const brandIcons = await import("./src/BrandIcons.res.js");
-assert.match(Object.keys(brandIcons).join(", "), /ReScript, BrandIcons\$ReScript, BrandIcons\$ReScript\$jsx, getIconForLanguageExtension/);
+assert.deepStrictEqual(
+  new Set(Object.keys(brandIcons)),
+  new Set([
+    "ReScript",
+    "BrandIcons$ReScript",
+    "BrandIcons$ReScript$jsx",
+    "getIconForLanguageExtension",
+  ]),
+);
+
+const multipleNested = await import("./src/MultipleNested.res.js");
+assert.deepStrictEqual(
+  new Set(Object.keys(multipleNested)),
+  new Set([
+    "Group",
+    "MultipleNested$Group",
+    "MultipleNested$Group$jsx",
+    "Other",
+    "MultipleNested$Other",
+    "MultipleNested$Other$jsx",
+  ]),
+);
 
 await execClean();

tests/build_tests/react_ppx/src/gpr_3987_test.res.js

@@ -3,10 +3,9 @@ module ReScript = {
   let make = () => React.null
 }
 
-
 let getIconForLanguageExtension = (language: string) => {
   switch language {
-  | "res" | "rescript" => <ReScript  />
+  | "res" | "rescript" => <ReScript />
   | _ => React.null
   }
 }

tests/build_tests/react_ppx/src/issue_7917_test.res.js

@@ -0,0 +1,13 @@
+module Group = {
+  @react.component
+  let make = (~children) => {
+    children
+  }
+}
+
+module Other = {
+  @react.component
+  let make = (~children) => {
+    children
+  }
+}

tests/build_tests/rsc_nested_jsx_deep/input.js

@@ -99,4 +99,8 @@ module Uncurried = {
     \"Newtype$Uncurried"
   }
 }
+let \"Newtype$V4A" = V4A.make and \"Newtype$V4A$jsx" = true
+let \"Newtype$V4A1" = V4A1.make and \"Newtype$V4A1$jsx" = true
+let \"Newtype$V4A2" = V4A2.make and \"Newtype$V4A2$jsx" = true
+let \"Newtype$V4A3" = V4A3.make and \"Newtype$V4A3$jsx" = true
 let \"Newtype$Uncurried" = Uncurried.make and \"Newtype$Uncurried$jsx" = true

tests/build_tests/rsc_nested_jsx_deep/src/BrandIcons.res

@@ -116,6 +116,7 @@ module Rec2 = {
   }
   and mm = x => make(x)
 }
+let \"V4$Uncurried" = Uncurried.make and \"V4$Uncurried$jsx" = true
 let \"V4$E" = E.make and \"V4$E$jsx" = true
 let \"V4$EUncurried" = EUncurried.make and \"V4$EUncurried$jsx" = true
 let \"V4$Rec" = Rec.make and \"V4$Rec$jsx" = true