Implement information byte in Server Reference ID and other optimizat…

…ions (#71463)

With this PR, we're adding one extra leading byte to Server Reference
IDs (both Server Actions and `"use cache"` functions), to include some
static information about the function itself.

The information byte has the following format:

```
0     000000    0
^type ^arg mask ^rest args
```

The type bit represents if the action is a cache function or not. For
cache functions, the type bit is set to `1`. Otherwise, it's `0`.

The arg mask bit is used to determine which arguments are used by the
function itself, up to 6 arguments. The bit is set to `1` if the
argument is used, or being spread or destructured (so it can be
indirectly or partially used). The bit is set to `0` otherwise.

The rest args bit is used to determine if there's a `...` rest argument
in the function signature. If there is, the bit is set to `1`.

For example:

```tsx
async function foo(a, foo, b, bar, ...baz) {
  'use cache';
  return a + b;
}
```

will have it encoded as `[1][101011][1]`. The first bit is set to `1`
because it's a cache function. The second part has `1010` because the
only arguments used are `a` and `b`. The subsequent `11` bits are set to
`1` because there's a `...baz` argument starting from the 5th. The last
bit is set to `1` as well for the same reason.

Note: Currently in this PR we don't track if an argument is actually
referenced in the function body or not. That will be implemented as a
follow-up optimization.

Also, the reference ID is currently hex-encoded so there will be exact 2
characters for easier decoding. This encoding might change though.

With this extra byte, the client can do some further optimizations. More
details can be found in the code comment.

crates/next-custom-transforms/tests/errors/server-actions/server-graph/1/output.js

@@ -1,8 +1,8 @@
-/* __next_internal_action_entry_do_not_use__ {"ab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00ab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export function foo() {}
 import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     foo
 ]);
-registerServerReference(foo, "ab21efdafbe611287bc25c0462b1e0510d13e48b", null);
+registerServerReference(foo, "00ab21efdafbe611287bc25c0462b1e0510d13e48b", null);

crates/next-custom-transforms/tests/errors/server-actions/server-graph/2/output.js

@@ -1,9 +1,9 @@
-/* __next_internal_action_entry_do_not_use__ {"ac840dcaf5e8197cb02b7f3a43c119b7a770b272":"bar"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00ac840dcaf5e8197cb02b7f3a43c119b7a770b272":"bar"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 'use strict';
 export function bar() {}
 import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     bar
 ]);
-registerServerReference(bar, "ac840dcaf5e8197cb02b7f3a43c119b7a770b272", null);
+registerServerReference(bar, "00ac840dcaf5e8197cb02b7f3a43c119b7a770b272", null);

crates/next-custom-transforms/tests/errors/server-actions/server-graph/6/output.js

@@ -1,4 +1,4 @@
-/* __next_internal_action_entry_do_not_use__ {"c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export default $$RSC_SERVER_ACTION_0 = ()=>{};
 var $$RSC_SERVER_ACTION_0;
@@ -10,4 +10,4 @@ import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     $$RSC_SERVER_ACTION_0
 ]);
-registerServerReference($$RSC_SERVER_ACTION_0, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference($$RSC_SERVER_ACTION_0, "00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);

crates/next-custom-transforms/tests/errors/server-actions/server-graph/8/output.js

@@ -1,9 +1,9 @@
-/* __next_internal_action_entry_do_not_use__ {"6a88810ecce4a4e8b59d53b8327d7e98bbf251d7":"$$RSC_SERVER_ACTION_0"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"006a88810ecce4a4e8b59d53b8327d7e98bbf251d7":"$$RSC_SERVER_ACTION_0"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export const $$RSC_SERVER_ACTION_0 = async function foo() {
     'use strict';
 };
-const foo = registerServerReference($$RSC_SERVER_ACTION_0, "6a88810ecce4a4e8b59d53b8327d7e98bbf251d7", null);
+const foo = registerServerReference($$RSC_SERVER_ACTION_0, "006a88810ecce4a4e8b59d53b8327d7e98bbf251d7", null);
 const bar = async ()=>{
     const x = 1;
     // prettier-ignore

crates/next-custom-transforms/tests/fixture/server-actions/client/2/output.js

@@ -1,3 +1,3 @@
 // app/send.ts
-/* __next_internal_action_entry_do_not_use__ {"ab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { createServerReference, callServer, findSourceMapURL } from "private-next-rsc-action-client-wrapper";
-export var foo = /*#__PURE__*/ createServerReference("ab21efdafbe611287bc25c0462b1e0510d13e48b", callServer, void 0, findSourceMapURL, "foo");
+/* __next_internal_action_entry_do_not_use__ {"7fab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { createServerReference, callServer, findSourceMapURL } from "private-next-rsc-action-client-wrapper";
+export var foo = /*#__PURE__*/ createServerReference("7fab21efdafbe611287bc25c0462b1e0510d13e48b", callServer, void 0, findSourceMapURL, "foo");

crates/next-custom-transforms/tests/fixture/server-actions/server/1/output.js

@@ -1,20 +1,20 @@
-/* __next_internal_action_entry_do_not_use__ {"6a88810ecce4a4e8b59d53b8327d7e98bbf251d7":"$$RSC_SERVER_ACTION_0","90b5db271335765a4b0eab01f044b381b5ebd5cd":"$$RSC_SERVER_ACTION_1"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"006a88810ecce4a4e8b59d53b8327d7e98bbf251d7":"$$RSC_SERVER_ACTION_0","0090b5db271335765a4b0eab01f044b381b5ebd5cd":"$$RSC_SERVER_ACTION_1"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 import deleteFromDb from 'db';
 export const $$RSC_SERVER_ACTION_0 = async function deleteItem($$ACTION_CLOSURE_BOUND) {
-    var [$$ACTION_ARG_0, $$ACTION_ARG_1] = await decryptActionBoundArgs("6a88810ecce4a4e8b59d53b8327d7e98bbf251d7", $$ACTION_CLOSURE_BOUND);
+    var [$$ACTION_ARG_0, $$ACTION_ARG_1] = await decryptActionBoundArgs("006a88810ecce4a4e8b59d53b8327d7e98bbf251d7", $$ACTION_CLOSURE_BOUND);
     await deleteFromDb($$ACTION_ARG_0);
     await deleteFromDb($$ACTION_ARG_1);
 };
 export function Item({ id1, id2 }) {
-    var deleteItem = registerServerReference($$RSC_SERVER_ACTION_0, "6a88810ecce4a4e8b59d53b8327d7e98bbf251d7", null).bind(null, encryptActionBoundArgs("6a88810ecce4a4e8b59d53b8327d7e98bbf251d7", [
+    var deleteItem = registerServerReference($$RSC_SERVER_ACTION_0, "006a88810ecce4a4e8b59d53b8327d7e98bbf251d7", null).bind(null, encryptActionBoundArgs("006a88810ecce4a4e8b59d53b8327d7e98bbf251d7", [
         id1,
         id2
     ]));
     return <Button action={deleteItem}>Delete</Button>;
 }
 export const $$RSC_SERVER_ACTION_1 = async function action($$ACTION_CLOSURE_BOUND) {
-    var [$$ACTION_ARG_0, $$ACTION_ARG_1] = await decryptActionBoundArgs("90b5db271335765a4b0eab01f044b381b5ebd5cd", $$ACTION_CLOSURE_BOUND);
+    var [$$ACTION_ARG_0, $$ACTION_ARG_1] = await decryptActionBoundArgs("0090b5db271335765a4b0eab01f044b381b5ebd5cd", $$ACTION_CLOSURE_BOUND);
     console.log($$ACTION_ARG_0);
     console.log($$ACTION_ARG_1);
 };
@@ -23,7 +23,7 @@ export default function Home() {
         name: 'John',
         test: 'test'
     };
-    const action = registerServerReference($$RSC_SERVER_ACTION_1, "90b5db271335765a4b0eab01f044b381b5ebd5cd", null).bind(null, encryptActionBoundArgs("90b5db271335765a4b0eab01f044b381b5ebd5cd", [
+    const action = registerServerReference($$RSC_SERVER_ACTION_1, "0090b5db271335765a4b0eab01f044b381b5ebd5cd", null).bind(null, encryptActionBoundArgs("0090b5db271335765a4b0eab01f044b381b5ebd5cd", [
         info.name,
         info.test
     ]));

crates/next-custom-transforms/tests/fixture/server-actions/server/10/output.js

@@ -1,8 +1,8 @@
-/* __next_internal_action_entry_do_not_use__ {"c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export default async function foo() {}
 import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     foo
 ]);
-registerServerReference(foo, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference(foo, "00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);

crates/next-custom-transforms/tests/fixture/server-actions/server/11/output.js

@@ -1,4 +1,4 @@
-/* __next_internal_action_entry_do_not_use__ {"c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export default async function $$RSC_SERVER_ACTION_0() {}
 Object.defineProperty($$RSC_SERVER_ACTION_0, "name", {
@@ -9,4 +9,4 @@ import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     $$RSC_SERVER_ACTION_0
 ]);
-registerServerReference($$RSC_SERVER_ACTION_0, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference($$RSC_SERVER_ACTION_0, "00c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);

crates/next-custom-transforms/tests/fixture/server-actions/server/12/output.js

@@ -1,9 +1,9 @@
-/* __next_internal_action_entry_do_not_use__ {"c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"7fc18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 async function foo() {}
 export default foo;
 import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     foo
 ]);
-registerServerReference(foo, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference(foo, "7fc18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);

crates/next-custom-transforms/tests/fixture/server-actions/server/13/output.js

@@ -1,4 +1,4 @@
-/* __next_internal_action_entry_do_not_use__ {"ac840dcaf5e8197cb02b7f3a43c119b7a770b272":"bar","c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"7fac840dcaf5e8197cb02b7f3a43c119b7a770b272":"bar","7fc18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 const foo = async function() {};
 export default foo;
@@ -9,5 +9,5 @@ ensureServerEntryExports([
     foo,
     bar
 ]);
-registerServerReference(foo, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
-registerServerReference(bar, "ac840dcaf5e8197cb02b7f3a43c119b7a770b272", null);
+registerServerReference(foo, "7fc18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference(bar, "7fac840dcaf5e8197cb02b7f3a43c119b7a770b272", null);

crates/next-custom-transforms/tests/fixture/server-actions/server/14/output.js

@@ -1,4 +1,4 @@
-/* __next_internal_action_entry_do_not_use__ {"ab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"00ab21efdafbe611287bc25c0462b1e0510d13e48b":"foo"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export async function foo() {
     async function bar() {}
@@ -7,4 +7,4 @@ import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     foo
 ]);
-registerServerReference(foo, "ab21efdafbe611287bc25c0462b1e0510d13e48b", null);
+registerServerReference(foo, "00ab21efdafbe611287bc25c0462b1e0510d13e48b", null);

crates/next-custom-transforms/tests/fixture/server-actions/server/15/output.js

@@ -1,4 +1,4 @@
-/* __next_internal_action_entry_do_not_use__ {"c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
+/* __next_internal_action_entry_do_not_use__ {"60c18c215a6b7cdc64bf709f3a714ffdef1bf9651d":"default"} */ import { registerServerReference } from "private-next-rsc-server-reference";
 import { encryptActionBoundArgs, decryptActionBoundArgs } from "private-next-rsc-action-encryption";
 export default $$RSC_SERVER_ACTION_0 = async (a, b)=>{
     console.log(a, b);
@@ -12,4 +12,4 @@ import { ensureServerEntryExports } from "private-next-rsc-action-validate";
 ensureServerEntryExports([
     $$RSC_SERVER_ACTION_0
 ]);
-registerServerReference($$RSC_SERVER_ACTION_0, "c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);
+registerServerReference($$RSC_SERVER_ACTION_0, "60c18c215a6b7cdc64bf709f3a714ffdef1bf9651d", null);