1 files changed, 168 insertions, 0 deletions
diff --git a/snapshots/build_runtime.rs b/snapshots/build_runtime.rs
new file mode 100644
index 000000000..ae1c67322
--- /dev/null
+++ b/snapshots/build_runtime.rs
@@ -0,0 +1,168 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+use std::convert::TryFrom;
+use std::path::Path;
+
+use deno_runtime::deno_broadcast_channel;
+use deno_runtime::deno_console;
+use deno_runtime::deno_core;
+use deno_runtime::deno_crypto;
+use deno_runtime::deno_fetch;
+use deno_runtime::deno_ffi;
+use deno_runtime::deno_http;
+use deno_runtime::deno_net;
+use deno_runtime::deno_tls;
+use deno_runtime::deno_url;
+use deno_runtime::deno_web;
+use deno_runtime::deno_webgpu;
+use deno_runtime::deno_webidl;
+use deno_runtime::deno_websocket;
+use deno_runtime::deno_webstorage;
+
+use deno_core::Extension;
+use deno_core::JsRuntime;
+use deno_core::RuntimeOptions;
+
+pub fn create_runtime_snapshot(snapshot_path: &Path) {
+  let extensions: Vec<Extension> = vec![
+    deno_webidl::init(),
+    deno_console::init(),
+    deno_url::init(),
+    deno_tls::init(),
+    deno_web::init::<Permissions>(
+      deno_web::BlobStore::default(),
+      Default::default(),
+    ),
+    deno_fetch::init::<Permissions>(Default::default()),
+    deno_websocket::init::<Permissions>("".to_owned(), None, None),
+    deno_webstorage::init(None),
+    deno_crypto::init(None),
+    deno_webgpu::init(false),
+    deno_broadcast_channel::init(
+      deno_broadcast_channel::InMemoryBroadcastChannel::default(),
+      false, // No --unstable.
+    ),
+    deno_ffi::init::<Permissions>(false),
+    deno_net::init::<Permissions>(
+      None, false, // No --unstable.
+      None,
+    ),
+    deno_http::init(),
+    // Runtime JS
+    deno_runtime::js::init(),
+  ];
+
+  let js_runtime = JsRuntime::new(RuntimeOptions {
+    will_snapshot: true,
+    extensions,
+    ..Default::default()
+  });
+  write_runtime_snapshot(js_runtime, snapshot_path);
+}
+
+// TODO(bartlomieju): this module contains a lot of duplicated
+// logic with `build_tsc.rs`
+fn write_runtime_snapshot(mut js_runtime: JsRuntime, snapshot_path: &Path) {
+  let snapshot = js_runtime.snapshot();
+  let snapshot_slice: &[u8] = &*snapshot;
+  println!("Snapshot size: {}", snapshot_slice.len());
+
+  let compressed_snapshot_with_size = {
+    let mut vec = vec![];
+
+    vec.extend_from_slice(
+      &u32::try_from(snapshot.len())
+        .expect("snapshot larger than 4gb")
+        .to_le_bytes(),
+    );
+
+    lzzzz::lz4_hc::compress_to_vec(
+      snapshot_slice,
+      &mut vec,
+      lzzzz::lz4_hc::CLEVEL_MAX,
+    )
+    .expect("snapshot compression failed");
+
+    vec
+  };
+
+  println!(
+    "Snapshot compressed size: {}",
+    compressed_snapshot_with_size.len()
+  );
+
+  std::fs::write(&snapshot_path, compressed_snapshot_with_size).unwrap();
+  println!("Snapshot written to: {} ", snapshot_path.display());
+}
+
+struct Permissions;
+
+impl deno_fetch::FetchPermissions for Permissions {
+  fn check_net_url(
+    &mut self,
+    _url: &deno_core::url::Url,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+
+  fn check_read(
+    &mut self,
+    _p: &Path,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+}
+
+impl deno_websocket::WebSocketPermissions for Permissions {
+  fn check_net_url(
+    &mut self,
+    _url: &deno_core::url::Url,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+}
+
+impl deno_web::TimersPermission for Permissions {
+  fn allow_hrtime(&mut self) -> bool {
+    unreachable!("snapshotting!")
+  }
+
+  fn check_unstable(
+    &self,
+    _state: &deno_core::OpState,
+    _api_name: &'static str,
+  ) {
+    unreachable!("snapshotting!")
+  }
+}
+
+impl deno_ffi::FfiPermissions for Permissions {
+  fn check(
+    &mut self,
+    _path: Option<&Path>,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+}
+
+impl deno_net::NetPermissions for Permissions {
+  fn check_net<T: AsRef<str>>(
+    &mut self,
+    _host: &(T, Option<u16>),
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+
+  fn check_read(
+    &mut self,
+    _p: &Path,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+
+  fn check_write(
+    &mut self,
+    _p: &Path,
+  ) -> Result<(), deno_core::error::AnyError> {
+    unreachable!("snapshotting!")
+  }
+}