feat(cli/dts): stricter typings for Listener & Conn (#10012)

cli/dts/lib.deno.ns.d.ts

@@ -1740,26 +1740,28 @@ declare namespace Deno {
   export type Addr = NetAddr | UnixAddr;
 
   /** A generic network listener for stream-oriented protocols. */
-  export interface Listener extends AsyncIterable<Conn> {
+  export interface Listener<Address extends Addr = Addr>
+    extends AsyncIterable<Conn<Address>> {
     /** Waits for and resolves to the next connection to the `Listener`. */
-    accept(): Promise<Conn>;
+    accept(): Promise<Conn<Address>>;
     /** Close closes the listener. Any pending accept promises will be rejected
      * with errors. */
     close(): void;
     /** Return the address of the `Listener`. */
-    readonly addr: Addr;
+    readonly addr: Address;
 
     /** Return the rid of the `Listener`. */
     readonly rid: number;
 
-    [Symbol.asyncIterator](): AsyncIterableIterator<Conn>;
+    [Symbol.asyncIterator](): AsyncIterableIterator<Conn<Address>>;
   }
 
-  export interface Conn extends Reader, Writer, Closer {
+  export interface Conn<Address extends Addr = Addr>
+    extends Reader, Writer, Closer {
     /** The local address of the connection. */
-    readonly localAddr: Addr;
+    readonly localAddr: Address;
     /** The remote address of the connection. */
-    readonly remoteAddr: Addr;
+    readonly remoteAddr: Address;
     /** The resource ID of the connection. */
     readonly rid: number;
     /** Shuts down (`shutdown(2)`) the write side of the connection. Most
@@ -1787,7 +1789,7 @@ declare namespace Deno {
    * Requires `allow-net` permission. */
   export function listen(
     options: ListenOptions & { transport?: "tcp" },
-  ): Listener;
+  ): Listener<NetAddr>;
 
   export interface ListenTlsOptions extends ListenOptions {
     /** Server certificate file. */
@@ -1806,7 +1808,7 @@ declare namespace Deno {
    * ```
    *
    * Requires `allow-net` permission. */
-  export function listenTls(options: ListenTlsOptions): Listener;
+  export function listenTls(options: ListenTlsOptions): Listener<NetAddr>;
 
   export interface ConnectOptions {
     /** The port to connect to. */
@@ -1829,7 +1831,7 @@ declare namespace Deno {
    * ```
    *
    * Requires `allow-net` permission for "tcp". */
-  export function connect(options: ConnectOptions): Promise<Conn>;
+  export function connect(options: ConnectOptions): Promise<Conn<NetAddr>>;
 
   export interface ConnectTlsOptions {
     /** The port to connect to. */
@@ -1855,7 +1857,9 @@ declare namespace Deno {
    *
    * Requires `allow-net` permission.
    */
-  export function connectTls(options: ConnectTlsOptions): Promise<Conn>;
+  export function connectTls(
+    options: ConnectTlsOptions,
+  ): Promise<Conn<NetAddr>>;
 
   /** Shutdown socket send operations.
    *

cli/dts/lib.deno.unstable.d.ts

@@ -909,7 +909,7 @@ declare namespace Deno {
    * Requires `allow-read` and `allow-write` permission. */
   export function listen(
     options: UnixListenOptions & { transport: "unix" },
-  ): Listener;
+  ): Listener<UnixAddr>;
 
   /** **UNSTABLE**: new API, yet to be vetted
    *
@@ -969,8 +969,11 @@ declare namespace Deno {
    *
    * Requires `allow-net` permission for "tcp" and `allow-read` for "unix". */
   export function connect(
-    options: ConnectOptions | UnixConnectOptions,
-  ): Promise<Conn>;
+    options: ConnectOptions,
+  ): Promise<Conn<NetAddr>>;
+  export function connect(
+    options: UnixConnectOptions,
+  ): Promise<Conn<UnixAddr>>;
 
   export interface StartTlsOptions {
     /** A literal IP address or host name that can be resolved to an IP address.
@@ -997,9 +1000,9 @@ declare namespace Deno {
    * Requires `allow-net` permission.
    */
   export function startTls(
-    conn: Conn,
+    conn: Conn<NetAddr>,
     options?: StartTlsOptions,
-  ): Promise<Conn>;
+  ): Promise<Conn<NetAddr>>;
 
   export interface ListenTlsOptions {
     /** **UNSTABLE**: new API, yet to be vetted.

cli/tests/unit/net_test.ts

@@ -18,6 +18,12 @@ unitTest({ perms: { net: true } }, function netTcpListenClose(): void {
   listener.close();
 });
 
+unitTest({ perms: { net: true } }, function netListenPortType(): void {
+  const listener = Deno.listen({ port: 0, transport: "tcp" });
+  listener.addr.port;
+  listener.close();
+});
+
 unitTest(
   {
     perms: { net: true },