ast, cgen: fix generic closures with different generic types (fix #17829) (#17834)

cmd/tools/vast/vast.v

@@ -581,7 +581,11 @@ fn (t Tree) anon_fn(node ast.AnonFn) &Node {
 	obj.add_terse('decl', t.fn_decl(node.decl))
 	obj.add('inherited_vars', t.array_node_arg(node.inherited_vars))
 	obj.add_terse('typ', t.type_node(node.typ))
-	obj.add('has_gen', t.bool_node(node.has_gen))
+	symbol_obj := new_object()
+	for key, val in node.has_gen {
+		symbol_obj.add_terse(key.str(), t.bool_node(val))
+	}
+	obj.add_terse('has_gen', symbol_obj)
 	return obj
 }
 

vlib/v/ast/ast.v

@@ -508,7 +508,7 @@ pub mut:
 	decl           FnDecl
 	inherited_vars []Param
 	typ            Type // the type of anonymous fn. Both .typ and .decl.name are auto generated
-	has_gen        bool // has been generated
+	has_gen        map[string]bool // has been generated
 }
 
 // function or method declaration

vlib/v/gen/c/fn.v

@@ -204,7 +204,7 @@ fn (mut g Gen) gen_fn_decl(node &ast.FnDecl, skip bool) {
 	is_closure := node.scope.has_inherited_vars()
 	mut cur_closure_ctx := ''
 	if is_closure {
-		cur_closure_ctx = closure_ctx(node)
+		cur_closure_ctx = g.closure_ctx(node)
 		// declare the struct before its implementation
 		g.definitions.write_string(cur_closure_ctx)
 		g.definitions.writeln(';')
@@ -461,8 +461,12 @@ fn (mut g Gen) c_fn_name(node &ast.FnDecl) !string {
 
 const closure_ctx = '_V_closure_ctx'
 
-fn closure_ctx(node ast.FnDecl) string {
-	return 'struct _V_${node.name}_Ctx'
+fn (mut g Gen) closure_ctx(node ast.FnDecl) string {
+	mut fn_name := node.name
+	if node.generic_names.len > 0 {
+		fn_name = g.generic_fn_name(g.cur_concrete_types, fn_name)
+	}
+	return 'struct _V_${fn_name}_Ctx'
 }
 
 fn (mut g Gen) gen_anon_fn(mut node ast.AnonFn) {
@@ -476,7 +480,7 @@ fn (mut g Gen) gen_anon_fn(mut node ast.AnonFn) {
 		g.write(fn_name)
 		return
 	}
-	ctx_struct := closure_ctx(node.decl)
+	ctx_struct := g.closure_ctx(node.decl)
 	// it may be possible to optimize `memdup` out if the closure never leaves current scope
 	// TODO in case of an assignment, this should only call "__closure_set_data" and "__closure_set_function" (and free the former data)
 	g.write('__closure_create(${fn_name}, (${ctx_struct}*) memdup_uncollectable(&(${ctx_struct}){')
@@ -520,14 +524,18 @@ fn (mut g Gen) gen_anon_fn(mut node ast.AnonFn) {
 }
 
 fn (mut g Gen) gen_anon_fn_decl(mut node ast.AnonFn) {
-	if node.has_gen {
+	mut fn_name := node.decl.name
+	if node.decl.generic_names.len > 0 {
+		fn_name = g.generic_fn_name(g.cur_concrete_types, fn_name)
+	}
+	if node.has_gen[fn_name] {
 		return
 	}
-	node.has_gen = true
+	node.has_gen[fn_name] = true
 	mut builder := strings.new_builder(256)
 	builder.writeln('/*F*/')
 	if node.inherited_vars.len > 0 {
-		ctx_struct := closure_ctx(node.decl)
+		ctx_struct := g.closure_ctx(node.decl)
 		builder.writeln('${ctx_struct} {')
 		for var in node.inherited_vars {
 			var_sym := g.table.sym(var.typ)

vlib/v/gen/js/fn.v

@@ -766,10 +766,14 @@ fn (mut g JsGen) fn_args(args []ast.Param, is_variadic bool) {
 }
 
 fn (mut g JsGen) gen_anon_fn(mut fun ast.AnonFn) {
-	if fun.has_gen {
+	mut fn_name := fun.decl.name
+	if fun.decl.generic_names.len > 0 {
+		fn_name = g.generic_fn_name(g.cur_concrete_types, fn_name)
+	}
+	if fun.has_gen[fn_name] {
 		return
 	}
-	fun.has_gen = true
+	fun.has_gen[fn_name] = true
 	it := fun.decl
 	cur_fn_decl := g.fn_decl
 	unsafe {

vlib/v/tests/generics_closures_with_different_generic_types_test.v

@@ -0,0 +1,17 @@
+fn abc[T](x T) fn (p T) T {
+	return fn [x] [T](p T) T {
+		return p * x
+	}
+}
+
+fn test_generic_closures_with_different_generic_types() {
+	f := abc[int](12345)
+	a := f(2)
+	dump(a)
+	assert a == 24690
+
+	g := abc[u8](5)
+	b := g(2)
+	dump(b)
+	assert b == 10
+}