Fix a socket connection problem

crates/els/inlay_hint.rs

@@ -252,10 +252,7 @@ impl<Checker: BuildRunnable> Server<Checker> {
                 // NG: f(proc:= i: T): U -> ...
                 // OK: f proc:= (i: T): U -> ...
                 let (name, col_begin) = if arg_is_lambda {
-                    (
-                        format!(" {name}"),
-                        col_begin.saturating_sub(1),
-                    )
+                    (format!(" {name}"), col_begin.saturating_sub(1))
                 } else {
                     (name.to_string(), col_begin)
                 };

crates/erg_compiler/context/register.rs

@@ -11,8 +11,8 @@ use erg_common::python_util::BUILTIN_PYTHON_MODS;
 use erg_common::set::Set;
 use erg_common::traits::{Locational, Stream};
 use erg_common::vis::Visibility;
-use erg_common::{enum_unwrap, get_hash, log, set};
 use erg_common::Str;
+use erg_common::{enum_unwrap, get_hash, log, set};
 
 use ast::{Decorator, DefId, Identifier, OperationKind, SimpleTypeSpec, VarName};
 use erg_parser::ast::{self, ConstIdentifier};

crates/erg_compiler/lib/pystd/os.d/__init__.d.er

@@ -1,6 +1,10 @@
 .path = pyimport "path"
 # .PathLike: ClassType
 
+'''
+The name of the operating system dependent module imported. The following names have currently been registered:
+    'posix', 'nt', 'java'.
+'''
 .name: Str
 
 .chdir!: (path: PathLike, ) => NoneType

crates/erg_compiler/lib/pystd/socket.d.er

@@ -1,2 +1,84 @@
+.AddressFamily: ClassType
+.AddressFamily <: Nat
+.AF_ALG: .AddressFamily # unix only
+.AF_APPLETALK: .AddressFamily
+.AF_ASH: .AddressFamily # unix only
+.AF_ATMPVC: .AddressFamily # unix only
+.AF_ATMSVC: .AddressFamily # unix only
+.AF_AX25: .AddressFamily
+.AF_BRIDGE: .AddressFamily # unix only
+.AF_BLUETOOTH: .AddressFamily
+.AF_CAN: .AddressFamily # unix only
+.AF_DECnet: .AddressFamily
+.AF_ECONET: .AddressFamily # unix only
+.AF_INET: .AddressFamily
+.AF_INET6: .AddressFamily
+.AF_IPX: .AddressFamily
+.AF_IRDA: .AddressFamily # unix only
+.AF_KEY: .AddressFamily # unix only
+.AF_LLC: .AddressFamily # unix only
+.AF_NETBEUI: .AddressFamily # unix only
+.AF_NETLINK: .AddressFamily # unix only
+.AF_NETROM: .AddressFamily
+.AF_PACKET: .AddressFamily # unix only
+.AF_PPPOX: .AddressFamily # unix only
+.AF_QIPCRTR: .AddressFamily # unix only
+.AF_RDS: .AddressFamily # unix only
+.AF_ROSE: .AddressFamily
+.AF_ROUTE: .AddressFamily # unix only
+.AF_SECURITY: .AddressFamily # unix only
+.AF_SNA: .AddressFamily
+.AF_TIPC: .AddressFamily # unix only
+.AF_UNIX: .AddressFamily # unix only
+.AF_UNSPEC: .AddressFamily
+.AF_VSOCK: .AddressFamily # unix only
+.AF_WANPIPE: .AddressFamily # unix only
+.AF_X25: .AddressFamily
+
+.SO_ACCEPTCONN: Nat
+.SO_BINDTODEVICE: Nat
+.SO_BROADCAST: Nat
+.SO_DEBUG: Nat
+.SO_DOMAIN: Nat
+.SO_DONTROUTE: Nat
+.SO_ERROR: Nat
+.SO_INCOMING_CPU: Nat
+.SO_J1939_ERRQUEUE: Nat
+.SO_J1939_FILTER: Nat
+.SO_J1939_PROMISC: Nat
+.SO_J1939_SEND_PRIO: Nat
+.SO_KEEPALIVE: Nat
+.SO_LINGER: Nat
+.SO_MARK: Nat
+.SO_OOBINLINE: Nat
+.SO_PASSCRED: Nat
+.SO_PASSSEC: Nat
+.SO_PEERCRED: Nat
+.SO_PEERSEC: Nat
+.SO_PRIORITY: Nat
+.SO_PROTOCOL: Nat
+.SO_RCVBUF: Nat
+.SO_RCVLOWAT: Nat
+.SO_RCVTIMEO: Nat
+.SO_REUSEADDR: Nat
+.SO_REUSEPORT: Nat
+.SO_SNDBUF: Nat
+.SO_SNDLOWAT: Nat
+.SO_SNDTIMEO: Nat
+.SO_TYPE: Nat
+.SO_VM_SOCKETS_BUFFER_MAX_SIZE: Nat
+.SO_VM_SOCKETS_BUFFER_MIN_SIZE: Nat
+.SO_VM_SOCKETS_BUFFER_SIZE: Nat
+
+.SOL_ALG: Nat
+.SOL_CAN_BASE: Nat
+.SOL_CAN_RAW: Nat
+.SOL_IP: Nat
+.SOL_RDS: Nat
+.SOL_SOCKET: Nat
+.SOL_TCP: Nat
+.SOL_TIPC: Nat
+.SOL_UDP: Nat
+
 .Socket!: ClassType
 .Socket!.new: (family := Int, type := Int, proto := Int, fileno: Int or NoneType := NoneType) -> .Socket!

crates/erg_compiler/lib/pystd/sys.d.er

@@ -6,6 +6,16 @@ io = pyimport "io"
 .copyright: Str
 .executable: Str
 .path: Array!(Str, _)
+'''
+* AIX -> 'aix'
+* FreeBSD -> 'freebsd'
+* Emscripten -> 'emscripten'
+* Linux -> 'linux'
+* WASI -> 'wasi'
+* Windows -> 'win32'
+* Windows/Cygwin -> 'cygwin'
+* macOS -> 'darwin'
+'''
 .platform: Str
 .prefix: Str
 .ps1: Str!

src/dummy.rs

@@ -213,6 +213,7 @@ fn find_available_port() -> u16 {
         .is_ok()
         .then_some(DEFAULT_PORT)
         .unwrap_or_else(|| {
+            // localhost:0 will bind to a free port
             let socket = SocketAddrV4::new(Ipv4Addr::LOCALHOST, 0);
             TcpListener::bind(socket)
                 .and_then(|listener| listener.local_addr())

src/scripts/repl_server.py

@@ -6,6 +6,8 @@ import importlib as __importlib
 import io as __io
 
 __server_socket = __socket.socket()
+if __sys.platform == 'linux':
+    __server_socket.setsockopt(__socket.SOL_SOCKET, __socket.SO_REUSEADDR, 1)
 # DummyVM will replace this __PORT__ with free port
 __server_socket.bind(('127.0.0.1', __PORT__))
 __server_socket.listen(1)