[Python] Add HashSet and NestedPattern tests, fix HashSet operations for native sets

pyrightconfig.ci.json

@@ -4,6 +4,8 @@
     "**/.venv/**",
     "**/node_modules/**",
     "temp/tests/Python/test_applicative.py",
+    "temp/tests/Python/test_hash_set.py",
+    "temp/tests/Python/test_nested_and_recursive_pattern.py",
     "temp/tests/Python/fable_modules/thoth_json_python/encode.py"
   ]
 }

src/Fable.Cli/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+* [Python] Fix HashSet operations (Count, Contains, Remove, UnionWith, IntersectWith, ExceptWith) to work with both native Python sets and custom MutableSet (by @dbrattli)
 * [Python] Fix `Array.length`, `.Length`, `Array.isEmpty`, and `ResizeArray.Count` to use `len()` instead of `.length` property for plain Python list interop (by @dbrattli)
 * [Python] Fix `Task<T>` pass-through returns not being awaited in if/else and try/with branches (by @dbrattli)
 * [Python] Fix `:? T as x` type test pattern in closures causing `UnboundLocalError` due to `cast()` shadowing outer variable (by @dbrattli)

src/Fable.Compiler/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+* [Python] Fix HashSet operations (Count, Contains, Remove, UnionWith, IntersectWith, ExceptWith) to work with both native Python sets and custom MutableSet (by @dbrattli)
 * [Python] Fix `Array.length`, `.Length`, `Array.isEmpty`, and `ResizeArray.Count` to use `len()` instead of `.length` property for plain Python list interop (by @dbrattli)
 * [Python] Fix `Task<T>` pass-through returns not being awaited in if/else and try/with branches (by @dbrattli)
 * [Python] Fix `:? T as x` type test pattern in closures causing `UnboundLocalError` due to `cast()` shadowing outer variable (by @dbrattli)

src/Fable.Transforms/Python/Fable2Python.Transforms.fs

@@ -3679,8 +3679,7 @@ let declareType
         let body, stmts = transformReflectionInfo com ctx None ent generics
         let expr, stmts' = makeFunctionExpression com ctx None (args, body, [], ta)
 
-        let name =
-            com.GetIdentifier(ctx, Naming.toPascalCase entName + Naming.reflectionSuffix)
+        let name = com.GetIdentifier(ctx, entName + Naming.reflectionSuffix)
 
         expr |> declareModuleMember com ctx ent.IsPublic name None, stmts @ stmts'
 
@@ -4065,8 +4064,7 @@ let transformUnion (com: IPythonCompiler) ctx (ent: Fable.Entity) (entName: stri
         let body, stmts = transformReflectionInfo com ctx None ent generics
         let expr, stmts' = makeFunctionExpression com ctx None (args, body, [], ta)
 
-        let name =
-            com.GetIdentifier(ctx, Naming.toPascalCase entName + Naming.reflectionSuffix)
+        let name = com.GetIdentifier(ctx, entName + Naming.reflectionSuffix)
 
         expr |> declareModuleMember com ctx ent.IsPublic name None, stmts @ stmts'
 

src/Fable.Transforms/Python/Replacements.fs

@@ -2630,17 +2630,25 @@ let hashSets (com: ICompiler) (ctx: Context) r t (i: CallInfo) (thisArg: Expr op
             |> makeHashSetWithComparer com r t (makeArray Any [])
             |> Some
         | _ -> None
-    | "get_Count", Some c, _ ->
-        Helper.LibCall(com, "mutable_set", "HashSet__get_Count", t, [ c ], ?loc = r)
-        |> Some
+    | "get_Count", Some c, _ -> Helper.GlobalCall("len", t, [ c ], ?loc = r) |> Some
     | "get_IsReadOnly", _, _ -> BoolConstant false |> makeValue r |> Some
-    | ReplaceName [ "Clear", "clear"; "Contains", "has"; "Remove", "delete" ] methName, Some c, args ->
-        Helper.InstanceCall(c, methName, t, args, i.SignatureArgTypes, ?loc = r) |> Some
+    | "Clear", Some c, _ -> Helper.InstanceCall(c, "clear", t, args, i.SignatureArgTypes, ?loc = r) |> Some
+    | "Contains", Some c, [ arg ] ->
+        Helper.LibCall(com, "map_util", "containsInSet", t, [ arg; c ], ?loc = r)
+        |> Some
+    | "Remove", Some c, [ arg ] ->
+        Helper.LibCall(com, "map_util", "removeFromSet", t, [ arg; c ], ?loc = r)
+        |> Some
     | "GetEnumerator", Some c, _ -> getEnumerator com r t c |> Some
     | "Add", Some c, [ arg ] -> Helper.LibCall(com, "map_util", "addToSet", t, [ arg; c ], ?loc = r) |> Some
-    | ("IsProperSubsetOf" | "IsProperSupersetOf" | "UnionWith" | "IntersectWith" | "ExceptWith" | "IsSubsetOf" | "IsSupersetOf" as meth),
-      Some c,
-      args ->
+    | "UnionWith", Some c, [ arg ] -> Helper.LibCall(com, "map_util", "unionWithSet", t, [ c; arg ], ?loc = r) |> Some
+    | "IntersectWith", Some c, [ arg ] ->
+        Helper.LibCall(com, "map_util", "intersectWithSet", t, [ c; arg ], ?loc = r)
+        |> Some
+    | "ExceptWith", Some c, [ arg ] ->
+        Helper.LibCall(com, "map_util", "exceptWithSet", t, [ c; arg ], ?loc = r)
+        |> Some
+    | ("IsProperSubsetOf" | "IsProperSupersetOf" | "IsSubsetOf" | "IsSupersetOf" as meth), Some c, args ->
         let meth = Naming.lowerFirst meth
         let args = injectArg com ctx r "Set" meth i.GenericArgs args
 

src/fable-library-py/fable_library/map_util.py

@@ -64,6 +64,40 @@ def add_to_set(v: object, st: MutableSet[object]) -> bool:
     return True
 
 
+def remove_from_set(v: object, st: MutableSet[object]) -> bool:
+    """Remove from set-like object - returns True if removed, False if not present."""
+    if v in st:
+        st.discard(v)
+        return True
+
+    return False
+
+
+def contains_in_set(v: object, st: MutableSet[object]) -> bool:
+    """Check if set-like object contains a value."""
+    return v in st
+
+
+def union_with_set(s1: MutableSet[object], s2: Iterable[object]) -> None:
+    """Add all elements from s2 to s1. Works with both native set and custom HashSet."""
+    for x in s2:
+        s1.add(x)
+
+
+def intersect_with_set(s1: MutableSet[object], s2: Iterable[object]) -> None:
+    """Remove elements from s1 that are not in s2. Works with both native set and custom HashSet."""
+    s2_items = set(s2)
+    to_remove = [x for x in s1 if x not in s2_items]
+    for x in to_remove:
+        s1.discard(x)
+
+
+def except_with_set(s1: MutableSet[object], s2: Iterable[object]) -> None:
+    """Remove all elements in s2 from s1. Works with both native set and custom HashSet."""
+    for x in s2:
+        s1.discard(x)
+
+
 def add_to_dict(di: dict[_K, _V], k: _K, v: _V) -> None:
     if k in di:
         raise Exception("An item with the same key has already been added. Key: " + str(k))

tests/Python/Fable.Tests.Python.fsproj

@@ -77,6 +77,8 @@
     <Compile Include="TestUri.fs" />
     <Compile Include="TestPyInterop.fs" />
     <Compile Include="TestPatternMatch.fs" />
+    <Compile Include="TestHashSet.fs" />
+    <Compile Include="TestNestedAndRecursivePattern.fs" />
 
     <Compile Include="TestNonRegression.fs" />
     <Compile Include="Main.fs" />