Fix JSX V4 build error when component props have the default value with same name

CHANGELOG.md

@@ -12,6 +12,10 @@
 
 # 11.0.0-rc.3 (Unreleased)
 
+#### :bug: Bug Fix
+
+- Fix issue with JSX V4 when component props have the default value with same name. https://github.com/rescript-lang/rescript-compiler/pull/6377
+
 # 11.0.0-rc.2
 
 #### :rocket: New Feature

jscomp/syntax/src/reactjs_jsx_v4.ml

@@ -634,7 +634,13 @@ let rec recursivelyTransformNamedArgsForMake expr args newtypes coreType =
     in
     let alias =
       match pattern with
-      | {ppat_desc = Ppat_alias (_, {txt}) | Ppat_var {txt}} -> txt
+      | {
+       ppat_desc =
+         ( Ppat_alias (_, {txt})
+         | Ppat_var {txt}
+         | Ppat_constraint ({ppat_desc = Ppat_var {txt}}, _) );
+      } ->
+        txt
       | {ppat_desc = Ppat_any} -> "_"
       | _ -> getLabel arg
     in
@@ -852,7 +858,7 @@ let vbMatch ~expr (name, default, _, alias, loc, _) =
       Vb.mk
         (Pat.var (Location.mkloc alias loc))
         (Exp.match_
-           (Exp.ident {txt = Lident alias; loc = Location.none})
+           (Exp.ident {txt = Lident ("__" ^ alias); loc = Location.none})
            [
              Exp.case
                (Pat.construct
@@ -978,6 +984,14 @@ let mapBinding ~config ~emptyLoc ~pstr_loc ~fileName ~recFlag binding =
         stripConstraintUnpack ~label pattern
       | _ -> pattern
     in
+    let safePatternLabel pattern =
+      match pattern with
+      | {ppat_desc = Ppat_var {txt; loc}} ->
+        {pattern with ppat_desc = Ppat_var {txt = "__" ^ txt; loc}}
+      | {ppat_desc = Ppat_alias (p, {txt; loc})} ->
+        {pattern with ppat_desc = Ppat_alias (p, {txt = "__" ^ txt; loc})}
+      | _ -> pattern
+    in
     let rec returnedExpression patternsWithLabel patternsWithNolabel
         ({pexp_desc} as expr) =
       match pexp_desc with
@@ -991,16 +1005,26 @@ let mapBinding ~config ~emptyLoc ~pstr_loc ~fileName ~recFlag binding =
             {ppat_desc = Ppat_construct ({txt = Lident "()"}, _)},
             expr ) ->
         (patternsWithLabel, patternsWithNolabel, expr)
-      | Pexp_fun (arg_label, _default, ({ppat_loc; ppat_desc} as pattern), expr)
+      | Pexp_fun (arg_label, default, ({ppat_loc; ppat_desc} as pattern), expr)
         -> (
         let patternWithoutConstraint =
           stripConstraintUnpack ~label:(getLabel arg_label) pattern
         in
+        (*
+           If prop has the default value as Ident, it will get a build error
+           when the referenced Ident value and the prop have the same name.
+           So we add a "__" to label to resolve the build error.
+        *)
+        let patternWithSafeLabel =
+          match default with
+          | Some _ -> safePatternLabel patternWithoutConstraint
+          | _ -> patternWithoutConstraint
+        in
         if isLabelled arg_label || isOptional arg_label then
           returnedExpression
             (( {loc = ppat_loc; txt = Lident (getLabel arg_label)},
                {
-                 patternWithoutConstraint with
+                 patternWithSafeLabel with
                  ppat_attributes =
                    (if isOptional arg_label then optionalAttrs else [])
                    @ pattern.ppat_attributes;

jscomp/syntax/tests/ppx/react/defaultValueProp.res

@@ -7,3 +7,16 @@ module C1 = {
   @react.component
   let make = (~a=2, ~b) => React.int(a + b)
 }
+
+module C2 = {
+  let a = "foo"
+  @react.component
+  let make = (~a=a) => React.string(a)
+}
+
+module C3 = {
+  @react.component
+  let make = (~disabled as everythingDisabled: bool=false) => {
+    React.string(everythingDisabled ? "true" : "false")
+  }
+}

jscomp/syntax/tests/ppx/react/expected/aliasProps.res.txt

@@ -3,8 +3,8 @@
 module C0 = {
   type props<'priority, 'text> = {priority: 'priority, text?: 'text}
 
-  let make = ({priority: _, ?text, _}: props<_, _>) => {
-    let text = switch text {
+  let make = ({priority: _, text: ?__text, _}: props<_, _>) => {
+    let text = switch __text {
     | Some(text) => text
     | None => "Test"
     }
@@ -21,8 +21,8 @@ module C0 = {
 module C1 = {
   type props<'priority, 'text> = {priority: 'priority, text?: 'text}
 
-  let make = ({priority: p, ?text, _}: props<_, _>) => {
-    let text = switch text {
+  let make = ({priority: p, text: ?__text, _}: props<_, _>) => {
+    let text = switch __text {
     | Some(text) => text
     | None => "Test"
     }
@@ -39,8 +39,8 @@ module C1 = {
 module C2 = {
   type props<'foo> = {foo?: 'foo}
 
-  let make = ({foo: ?bar, _}: props<_>) => {
-    let bar = switch bar {
+  let make = ({foo: ?__bar, _}: props<_>) => {
+    let bar = switch __bar {
     | Some(foo) => foo
     | None => ""
     }
@@ -57,12 +57,12 @@ module C2 = {
 module C3 = {
   type props<'foo, 'a, 'b> = {foo?: 'foo, a?: 'a, b: 'b}
 
-  let make = ({foo: ?bar, ?a, b, _}: props<_, _, _>) => {
-    let bar = switch bar {
+  let make = ({foo: ?__bar, a: ?__a, b, _}: props<_, _, _>) => {
+    let bar = switch __bar {
     | Some(foo) => foo
     | None => ""
     }
-    let a = switch a {
+    let a = switch __a {
     | Some(a) => a
     | None => bar
     }
@@ -81,8 +81,8 @@ module C3 = {
 module C4 = {
   type props<'a, 'x> = {a: 'a, x?: 'x}
 
-  let make = ({a: b, ?x, _}: props<_, _>) => {
-    let x = switch x {
+  let make = ({a: b, x: ?__x, _}: props<_, _>) => {
+    let x = switch __x {
     | Some(x) => x
     | None => true
     }
@@ -99,8 +99,8 @@ module C4 = {
 module C5 = {
   type props<'a, 'z> = {a: 'a, z?: 'z}
 
-  let make = ({a: (x, y), ?z, _}: props<_, _>) => {
-    let z = switch z {
+  let make = ({a: (x, y), z: ?__z, _}: props<_, _>) => {
+    let z = switch __z {
     | Some(z) => z
     | None => 3
     }

jscomp/syntax/tests/ppx/react/expected/defaultValueProp.res.txt

@@ -1,11 +1,11 @@
 module C0 = {
   type props<'a, 'b> = {a?: 'a, b?: 'b}
-  let make = ({?a, ?b, _}: props<_, _>) => {
-    let a = switch a {
+  let make = ({a: ?__a, b: ?__b, _}: props<_, _>) => {
+    let a = switch __a {
     | Some(a) => a
     | None => 2
     }
-    let b = switch b {
+    let b = switch __b {
     | Some(b) => b
     | None => a * 2
     }
@@ -21,8 +21,8 @@ module C0 = {
 module C1 = {
   type props<'a, 'b> = {a?: 'a, b: 'b}
 
-  let make = ({?a, b, _}: props<_, _>) => {
-    let a = switch a {
+  let make = ({a: ?__a, b, _}: props<_, _>) => {
+    let a = switch __a {
     | Some(a) => a
     | None => 2
     }
@@ -35,3 +35,42 @@ module C1 = {
     \"DefaultValueProp$C1"
   }
 }
+
+module C2 = {
+  let a = "foo"
+  type props<'a> = {a?: 'a}
+
+  let make = ({a: ?__a, _}: props<_>) => {
+    let a = switch __a {
+    | Some(a) => a
+    | None => a
+    }
+
+    React.string(a)
+  }
+  let make = {
+    let \"DefaultValueProp$C2" = (props: props<_>) => make(props)
+
+    \"DefaultValueProp$C2"
+  }
+}
+
+module C3 = {
+  type props<'disabled> = {disabled?: 'disabled}
+
+  let make = ({disabled: ?__everythingDisabled, _}: props<bool>) => {
+    let everythingDisabled = switch __everythingDisabled {
+    | Some(disabled) => disabled
+    | None => false
+    }
+
+    {
+      React.string(everythingDisabled ? "true" : "false")
+    }
+  }
+  let make = {
+    let \"DefaultValueProp$C3" = (props: props<_>) => make(props)
+
+    \"DefaultValueProp$C3"
+  }
+}

jscomp/syntax/tests/ppx/react/expected/uncurriedProps.res.txt

@@ -1,8 +1,8 @@
 @@jsxConfig({version: 4})
 type props<'a> = {a?: 'a}
 
-let make = ({?a, _}: props<(. unit) => unit>) => {
-  let a = switch a {
+let make = ({a: ?__a, _}: props<(. unit) => unit>) => {
+  let a = switch __a {
   | Some(a) => a
   | None => (. ()) => ()
   }
@@ -28,8 +28,8 @@ func(~callback=(. str, a, b) => {
 module Foo = {
   type props<'callback> = {callback?: 'callback}
 
-  let make = ({?callback, _}: props<(. string, bool, bool) => unit>) => {
-    let callback = switch callback {
+  let make = ({callback: ?__callback, _}: props<(. string, bool, bool) => unit>) => {
+    let callback = switch __callback {
     | Some(callback) => callback
     | None => (. _, _, _) => ()
     }