feat: granular --unstable-* flags (#20968)

This commit adds granular `--unstable-*` flags:
- "--unstable-broadcast-channel"
- "--unstable-ffi"
- "--unstable-fs"
- "--unstable-http"
- "--unstable-kv"
- "--unstable-net"
- "--unstable-worker-options"
- "--unstable-cron"

These flags are meant to replace a "catch-all" flag - "--unstable", that
gives a binary control whether unstable features are enabled or not. The
downside of this flag that allowing eg. Deno KV API also enables the FFI
API (though the latter is still gated with a permission).

These flags can also be specified in `deno.json` file under `unstable`
key.

Currently, "--unstable" flag works the same way - I will open a follow
up PR that will print a warning when using "--unstable" and suggest to use
concrete "--unstable-*" flag instead. We plan to phase out "--unstable"
completely in Deno 2.

1 files changed, 35 insertions, 17 deletions

diff --git a/runtime/js/99_main.js b/runtime/js/99_main.js
index ac1f52e74..b06cef651 100644
--- a/runtime/js/99_main.js
+++ b/runtime/js/99_main.js
@@ -57,7 +57,11 @@ import * as performance from "ext:deno_web/15_performance.js";
 import * as url from "ext:deno_url/00_url.js";
 import * as fetch from "ext:deno_fetch/26_fetch.js";
 import * as messagePort from "ext:deno_web/13_message_port.js";
-import { denoNs, denoNsUnstable } from "ext:runtime/90_deno_ns.js";
+import {
+  denoNs,
+  denoNsUnstable,
+  denoNsUnstableById,
+} from "ext:runtime/90_deno_ns.js";
 import { errors } from "ext:runtime/01_errors.js";
 import * as webidl from "ext:deno_webidl/00_webidl.js";
 import DOMException from "ext:deno_web/01_dom_exception.js";
@@ -467,14 +471,15 @@ function bootstrapMainRuntime(runtimeOptions) {
     7: isTty,
     8: tsVersion,
     9: unstableFlag,
-    10: pid,
-    11: target,
-    12: v8Version,
-    13: userAgent,
-    14: inspectFlag,
-    // 15: enableTestingFeaturesFlag
-    16: hasNodeModulesDir,
-    17: maybeBinaryNpmCommandName,
+    10: unstableFeatures,
+    11: pid,
+    12: target,
+    13: v8Version,
+    14: userAgent,
+    15: inspectFlag,
+    // 16: enableTestingFeaturesFlag
+    17: hasNodeModulesDir,
+    18: maybeBinaryNpmCommandName,
   } = runtimeOptions;
 
   performance.setTimeOrigin(DateNow());
@@ -557,6 +562,7 @@ function bootstrapMainRuntime(runtimeOptions) {
     mainModule: util.getterOnly(opMainModule),
   });
 
+  // TODO(bartlomieju): deprecate --unstable
   if (unstableFlag) {
     ObjectAssign(finalDenoNs, denoNsUnstable);
     // TODO(bartlomieju): this is not ideal, but because we use `ObjectAssign`
@@ -576,6 +582,11 @@ function bootstrapMainRuntime(runtimeOptions) {
         jupyterNs = val;
       },
     });
+  } else {
+    for (let i = 0; i <= unstableFeatures.length; i++) {
+      const id = unstableFeatures[i];
+      ObjectAssign(finalDenoNs, denoNsUnstableById[id]);
+    }
   }
 
   // Setup `Deno` global - we're actually overriding already existing global
@@ -611,14 +622,15 @@ function bootstrapWorkerRuntime(
     7: isTty,
     8: tsVersion,
     9: unstableFlag,
-    10: pid,
-    11: target,
-    12: v8Version,
-    13: userAgent,
-    // 14: inspectFlag,
-    15: enableTestingFeaturesFlag,
-    16: hasNodeModulesDir,
-    17: maybeBinaryNpmCommandName,
+    10: unstableFeatures,
+    11: pid,
+    12: target,
+    13: v8Version,
+    14: userAgent,
+    // 15: inspectFlag,
+    16: enableTestingFeaturesFlag,
+    17: hasNodeModulesDir,
+    18: maybeBinaryNpmCommandName,
   } = runtimeOptions;
 
   performance.setTimeOrigin(DateNow());
@@ -688,8 +700,14 @@ function bootstrapWorkerRuntime(
 
   globalThis.pollForMessages = pollForMessages;
 
+  // TODO(bartlomieju): deprecate --unstable
   if (unstableFlag) {
     ObjectAssign(finalDenoNs, denoNsUnstable);
+  } else {
+    for (let i = 0; i <= unstableFeatures.length; i++) {
+      const id = unstableFeatures[i];
+      ObjectAssign(finalDenoNs, denoNsUnstableById[id]);
+    }
   }
   ObjectDefineProperties(finalDenoNs, {
     pid: util.readOnly(pid),