[JS/TS] Don't generate the setter code if a property is decorated wit…

…h `[<Erase>]`

Fix #3948

c

src/Fable.Cli/CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [TS] Make discriminated union `.Is*` properties works (@MangelMaxime)
 * [JS/TS/Python] Fix `h` in `DateTime.ToString` (@MangelMaxime)
 * [JS/TS] Fix `hh` in `DateTime.ToString` (@MangelMaxime)
+* [JS/TS] Don't generate the setter code if a property is decorated with `[<Erase>]` (@MangelMaxime)
 
 ## 5.0.0-alpha.3 - 2024-12-18
 

src/Fable.Transforms/FSharp2Fable.fs

@@ -1921,7 +1921,14 @@ let private transformMemberDecl
     elif isCompilerGenerated memb args then
         []
     // Ignore members that are decorated with [<Erase>]
-    elif hasAttrib Atts.erase memb.Attributes then
+    elif
+        hasAttrib Atts.erase memb.Attributes
+        // Attributes are not universally propagated so for setter properties we need
+        // to check the declaring entity, https://github.com/fable-compiler/Fable/issues/3948
+        || (memb.IsPropertySetterMethod
+            && memb.DeclaringEntity.IsSome
+            && hasAttrib Atts.erase memb.DeclaringEntity.Value.Attributes)
+    then
         []
     elif memb.IsOverrideOrExplicitInterfaceImplementation then
         if not memb.IsCompilerGenerated then

tests/Integration/Integration/data/eraseAttribute/ErasedTypeWithProperty.fs

@@ -0,0 +1,12 @@
+module ErasedTypeWithProperty
+
+open Fable.Core
+
+[<Erase>]
+type internal LanguageInjectionAttribute() =
+
+    [<Erase>]
+    member val Prefix = "" with get, set
+
+// Force Fable to generate a file, otherwise because everything is erased, it will not generate anything
+let a = 0

tests/Integration/Integration/data/eraseAttribute/ErasedTypeWithProperty.js.expected

@@ -0,0 +1,3 @@
+
+export const a = 0;
+

tests/Integration/Integration/data/eraseAttribute/eraseAttribute.fsproj

@@ -8,6 +8,7 @@
 
   <ItemGroup>
     <Compile Include="Members.fs" />
+    <Compile Include="ErasedTypeWithProperty.fs" />
   </ItemGroup>
 
   <ItemGroup>