feat(runtime): add a Cargo feature flag to enable the ffi API

runtime/00_ffi.js

@@ -0,0 +1,3 @@
+// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+
+// mock FFI interface in case the `ffi` Cargo feature is not enabled

runtime/Cargo.toml

@@ -10,6 +10,7 @@ repository.workspace = true
 description = "Provides the deno runtime library"
 
 [features]
+default = ["ffi"]
 # "fake" feature that allows to generate docs on docs.rs
 docsrs = []
 # A feature that allows excluding `./js/99_main.js` from the exported extension.
@@ -29,6 +30,8 @@ hmr = ["include_js_files_for_snapshotting", "transpile"]
 only_snapshotted_js_sources = ["include_js_files_for_snapshotting"]
 snapshot = ["transpile"]
 transpile = ["deno_ast"]
+# enable the FFI API
+ffi = ["deno_ffi"]
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(tokio_unstable)'] }
@@ -53,7 +56,7 @@ deno_cron.workspace = true
 deno_crypto.workspace = true
 deno_error.workspace = true
 deno_fetch.workspace = true
-deno_ffi.workspace = true
+deno_ffi = { workspace = true, optional = true }
 deno_fs = { workspace = true, features = ["sync_fs"] }
 deno_http.workspace = true
 deno_io.workspace = true

runtime/lib.rs

@@ -8,6 +8,7 @@ pub use deno_core;
 pub use deno_cron;
 pub use deno_crypto;
 pub use deno_fetch;
+#[cfg(feature = "ffi")]
 pub use deno_ffi;
 pub use deno_fs;
 pub use deno_http;
@@ -75,6 +76,7 @@ pub static UNSTABLE_GRANULAR_FLAGS: &[UnstableGranularFlag] = &[
     show_in_help: true,
     id: 2,
   },
+  #[cfg(feature = "ffi")]
   UnstableGranularFlag {
     name: deno_ffi::UNSTABLE_FEATURE_NAME,
     help_text: "Enable unstable FFI APIs",

runtime/shared.rs

@@ -4,6 +4,9 @@
 use deno_core::extension;
 use deno_core::Extension;
 
+#[cfg(not(feature = "ffi"))]
+extension!(deno_ffi, esm = ["00_ffi.js"]);
+
 extension!(runtime,
   deps = [
     deno_webidl,

runtime/snapshot.rs

@@ -58,6 +58,7 @@ impl deno_fetch::FetchPermissions for Permissions {
   }
 }
 
+#[cfg(feature = "ffi")]
 impl deno_ffi::FfiPermissions for Permissions {
   fn check_partial_no_path(&mut self) -> Result<(), PermissionCheckError> {
     unreachable!("snapshotting!")
@@ -293,7 +294,10 @@ pub fn create_runtime_snapshot(
     deno_broadcast_channel::deno_broadcast_channel::init_ops_and_esm(
       deno_broadcast_channel::InMemoryBroadcastChannel::default(),
     ),
+    #[cfg(feature = "ffi")]
     deno_ffi::deno_ffi::init_ops_and_esm::<Permissions>(),
+    #[cfg(not(feature = "ffi"))]
+    crate::shared::deno_ffi::init_ops_and_esm(),
     deno_net::deno_net::init_ops_and_esm::<Permissions>(None, None),
     deno_tls::deno_tls::init_ops_and_esm(),
     deno_kv::deno_kv::init_ops_and_esm(

runtime/web_worker.rs

@@ -496,7 +496,10 @@ impl WebWorker {
       deno_broadcast_channel::deno_broadcast_channel::init_ops_and_esm(
         services.broadcast_channel,
       ),
+      #[cfg(feature = "ffi")]
       deno_ffi::deno_ffi::init_ops_and_esm::<PermissionsContainer>(),
+      #[cfg(not(feature = "ffi"))]
+      crate::shared::deno_ffi::init_ops_and_esm(),
       deno_net::deno_net::init_ops_and_esm::<PermissionsContainer>(
         services.root_cert_store_provider.clone(),
         options.unsafely_ignore_certificate_errors.clone(),

runtime/worker.rs

@@ -395,7 +395,10 @@ impl MainWorker {
       deno_broadcast_channel::deno_broadcast_channel::init_ops_and_esm(
         services.broadcast_channel.clone(),
       ),
+      #[cfg(feature = "ffi")]
       deno_ffi::deno_ffi::init_ops_and_esm::<PermissionsContainer>(),
+      #[cfg(not(feature = "ffi"))]
+      crate::shared::deno_ffi::init_ops_and_esm(),
       deno_net::deno_net::init_ops_and_esm::<PermissionsContainer>(
         services.root_cert_store_provider.clone(),
         options.unsafely_ignore_certificate_errors.clone(),