From fa17df3f560e4e1bc618a72dd8fcb980fa6f196a Mon Sep 17 00:00:00 2001
From: Maxime Mangel <me@mangelmaxime.fr>
Date: Fri, 25 Oct 2024 22:12:12 +0200
Subject: [PATCH] [JS] Allow `[<Erase>]` to work on members (#3940)

---
 src/Fable.Cli/CHANGELOG.md                      |  1 +
 src/Fable.Transforms/FSharp2Fable.fs            |  3 +++
 .../Integration/Integration/CompilationTests.fs |  2 +-
 .../Integration/data/eraseAttribute/Members.fs  | 15 +++++++++++++++
 .../data/eraseAttribute/Members.js.expected     | 15 +++++++++++++++
 .../data/eraseAttribute/eraseAttribute.fsproj   | 17 +++++++++++++++++
 6 files changed, 52 insertions(+), 1 deletion(-)
 create mode 100644 tests/Integration/Integration/data/eraseAttribute/Members.fs
 create mode 100644 tests/Integration/Integration/data/eraseAttribute/Members.js.expected
 create mode 100644 tests/Integration/Integration/data/eraseAttribute/eraseAttribute.fsproj

diff --git a/src/Fable.Cli/CHANGELOG.md b/src/Fable.Cli/CHANGELOG.md
index f2d4e7acf2..22e32d7392 100644
--- a/src/Fable.Cli/CHANGELOG.md
+++ b/src/Fable.Cli/CHANGELOG.md
@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 * [Rust] Added decision tree multiple target references (by @ncave)
 * [Rust] Added Char surrogate tests for completeness (by @ncave)
 * [JS] Add `System.String.Normalize` support (by @DashieTM)
+* [JS] Allow `[<Erase>]` to work on members (by @MangelMaxime)
 
 ### Fixed
 
diff --git a/src/Fable.Transforms/FSharp2Fable.fs b/src/Fable.Transforms/FSharp2Fable.fs
index 68bba6663e..b4e46594c1 100644
--- a/src/Fable.Transforms/FSharp2Fable.fs
+++ b/src/Fable.Transforms/FSharp2Fable.fs
@@ -1920,6 +1920,9 @@ let private transformMemberDecl
     // Ignore members generated by the F# compiler (for comparison and equality)
     elif isCompilerGenerated memb args then
         []
+    // Ignore members that are decorated with [<Erase>]
+    elif hasAttrib Atts.erase memb.Attributes then
+        []
     elif memb.IsOverrideOrExplicitInterfaceImplementation then
         if not memb.IsCompilerGenerated then
             match memb.DeclaringEntity with
diff --git a/tests/Integration/Integration/CompilationTests.fs b/tests/Integration/Integration/CompilationTests.fs
index 1e1930856c..7591eb56de 100644
--- a/tests/Integration/Integration/CompilationTests.fs
+++ b/tests/Integration/Integration/CompilationTests.fs
@@ -10,7 +10,7 @@ let tests =
     Directory.EnumerateDirectories(data)
     |> Seq.map (fun testCaseDir -> //
         testCaseAsync
-            (Path.GetDirectoryName(testCaseDir))
+            testCaseDir
             (async {
                 let project =
                     Directory.GetFileSystemEntries(testCaseDir, "*.fsproj") |> Seq.exactlyOne
diff --git a/tests/Integration/Integration/data/eraseAttribute/Members.fs b/tests/Integration/Integration/data/eraseAttribute/Members.fs
new file mode 100644
index 0000000000..73b0961ef4
--- /dev/null
+++ b/tests/Integration/Integration/data/eraseAttribute/Members.fs
@@ -0,0 +1,15 @@
+module EraseAttributeMembers
+
+open Fable.Core
+
+type input() =
+
+    [<Erase>]
+    member this.onChange
+        with set (_: obj -> unit) = ()
+
+
+type input with
+
+    [<Erase>]
+    member this.onChange2 set (_: obj -> unit) = ()
diff --git a/tests/Integration/Integration/data/eraseAttribute/Members.js.expected b/tests/Integration/Integration/data/eraseAttribute/Members.js.expected
new file mode 100644
index 0000000000..756a8a1767
--- /dev/null
+++ b/tests/Integration/Integration/data/eraseAttribute/Members.js.expected
@@ -0,0 +1,15 @@
+import { class_type } from "./fable_modules/fable-library-js.4.22.0/Reflection.js";
+
+export class input {
+    constructor() {
+    }
+}
+
+export function input_$reflection() {
+    return class_type("EraseAttributeMembers.input", undefined, input);
+}
+
+export function input_$ctor() {
+    return new input();
+}
+
diff --git a/tests/Integration/Integration/data/eraseAttribute/eraseAttribute.fsproj b/tests/Integration/Integration/data/eraseAttribute/eraseAttribute.fsproj
new file mode 100644
index 0000000000..3fd6085760
--- /dev/null
+++ b/tests/Integration/Integration/data/eraseAttribute/eraseAttribute.fsproj
@@ -0,0 +1,17 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <RollForward>Major</RollForward>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Include="Members.fs" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Fable.Core" Version="4.2.0" />
+  </ItemGroup>
+
+</Project>