diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v index 3ec8b8a283..6e614cef61 100644 --- a/vlib/v/checker/checker.v +++ b/vlib/v/checker/checker.v @@ -3023,58 +3023,64 @@ fn (mut c Checker) resolve_generic_interface(typ ast.Type, interface_type ast.Ty utyp := c.unwrap_generic(typ) typ_sym := c.table.get_type_symbol(utyp) mut inter_sym := c.table.get_type_symbol(interface_type) + if mut inter_sym.info is ast.Interface { if inter_sym.info.is_generic { mut inferred_types := []ast.Type{} - for ifield in inter_sym.info.fields { - if ifield.typ.has_flag(.generic) { - if field := c.table.find_field_with_embeds(typ_sym, ifield.name) { - if field.typ !in inferred_types { - inferred_types << field.typ + generic_names := inter_sym.info.generic_types.map(c.table.get_type_name(it)) + // inferring interface generic types + for gt_name in generic_names { + mut inferred_type := ast.void_type + for ifield in inter_sym.info.fields { + if ifield.typ.has_flag(.generic) && c.table.get_type_name(ifield.typ) == gt_name { + if field := c.table.find_field_with_embeds(typ_sym, ifield.name) { + inferred_type = field.typ } } } + for imethod in inter_sym.info.methods { + method := typ_sym.find_method(imethod.name) or { + typ_sym.find_method_with_generic_parent(imethod.name) or { ast.Fn{} } + } + if imethod.return_type.has_flag(.generic) { + imret_sym := c.table.get_type_symbol(imethod.return_type) + mret_sym := c.table.get_type_symbol(method.return_type) + if imret_sym.info is ast.MultiReturn && mret_sym.info is ast.MultiReturn { + for i, mr_typ in imret_sym.info.types { + if mr_typ.has_flag(.generic) + && c.table.get_type_name(mr_typ) == gt_name { + inferred_type = mret_sym.info.types[i] + } + } + } else if c.table.get_type_name(imethod.return_type) == gt_name { + mut ret_typ := method.return_type + if imethod.return_type.has_flag(.optional) { + ret_typ = ret_typ.clear_flag(.optional) + } + inferred_type = ret_typ + } + } + for i, iparam in imethod.params { + param := method.params[i] or { ast.Param{} } + if iparam.typ.has_flag(.generic) + && c.table.get_type_name(iparam.typ) == gt_name { + inferred_type = param.typ + } + } + } + if inferred_type == ast.void_type { + c.error('could not infer generic type `$gt_name` in interface', pos) + return interface_type + } + inferred_types << inferred_type } + // add concrete types to method for imethod in inter_sym.info.methods { - method := typ_sym.find_method(imethod.name) or { - typ_sym.find_method_with_generic_parent(imethod.name) or { ast.Fn{} } - } - if imethod.return_type.has_flag(.generic) { - mut inferred_type := method.return_type - if imethod.return_type.has_flag(.optional) { - inferred_type = inferred_type.clear_flag(.optional) - } - if inferred_type !in inferred_types { - inferred_types << inferred_type - } - } - for i, iparam in imethod.params { - param := method.params[i] or { ast.Param{} } - if iparam.typ.has_flag(.generic) { - if param.typ !in inferred_types { - inferred_types << param.typ - } - } - } if inferred_types !in c.table.fn_generic_types[imethod.name] { c.table.fn_generic_types[imethod.name] << inferred_types } } - if inferred_types.len == 0 { - c.error('cannot infer generic types for ${c.table.type_to_str(interface_type)}', - pos) - return ast.void_type - } - if inferred_types.len > 1 { - c.error('cannot infer generic types for ${c.table.type_to_str(interface_type)}: got conflicting type information', - pos) - return ast.void_type - } - inferred_type := inferred_types[0] - if inferred_type !in inter_sym.info.concrete_types { - inter_sym.info.concrete_types << inferred_type - } - generic_names := inter_sym.info.generic_types.map(c.table.get_type_name(it)) + inter_sym.info.concrete_types = inferred_types return c.unwrap_generic_type(interface_type, generic_names, inter_sym.info.concrete_types) } } diff --git a/vlib/v/tests/generics_interface_with_multi_generic_types_test.v b/vlib/v/tests/generics_interface_with_multi_generic_types_test.v new file mode 100644 index 0000000000..7a88789c63 --- /dev/null +++ b/vlib/v/tests/generics_interface_with_multi_generic_types_test.v @@ -0,0 +1,37 @@ +interface Iter { + next() ?(T, U) +} + +struct ArrIter { + t []T + u []U +mut: + index int +} + +fn (mut it ArrIter) next() ?(T, U) { + if it.index >= it.t.len || it.index >= it.u.len { + return none + } + defer { + it.index++ + } + return it.t[it.index], it.u[it.index] +} + +fn iter(t []T, u []U) Iter { + return ArrIter{ + t: t + u: u + } +} + +fn test_generics_interface_with_multi_generic_types() { + mut x := iter([1, 2, 3], ['foo', 'bar', 'baz']) + ret := 0 + a, b := x.next() or { ret, '' } + println(a) + println(b) + assert a == 1 + assert b == 'foo' +}