refactor: Use ES modules for internal runtime code (#17648)

This PR refactors all internal js files (except core) to be written as
ES modules.
`__bootstrap`has been mostly replaced with static imports in form in
`internal:[path to file from repo root]`.
To specify if files are ESM, an `esm` method has been added to
`Extension`, similar to the `js` method.
A new ModuleLoader called `InternalModuleLoader` has been added to
enable the loading of internal specifiers, which is used in all
situations except when a snapshot is only loaded, and not a new one is
created from it.

---------

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 62 insertions, 67 deletions

diff --git a/runtime/js/40_signals.js b/runtime/js/40_signals.js
index ff1502a55..4ae310151 100644
--- a/runtime/js/40_signals.js
+++ b/runtime/js/40_signals.js
@@ -1,88 +1,83 @@
 // Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
-"use strict";
 
-((window) => {
-  const core = window.Deno.core;
-  const ops = core.ops;
-  const {
-    SafeSetIterator,
-    Set,
-    SetPrototypeDelete,
-    SymbolFor,
-    TypeError,
-  } = window.__bootstrap.primordials;
+const core = globalThis.Deno.core;
+const ops = core.ops;
+const primordials = globalThis.__bootstrap.primordials;
+const {
+  SafeSetIterator,
+  Set,
+  SetPrototypeDelete,
+  SymbolFor,
+  TypeError,
+} = primordials;
 
-  function bindSignal(signo) {
-    return ops.op_signal_bind(signo);
-  }
+function bindSignal(signo) {
+  return ops.op_signal_bind(signo);
+}
 
-  function pollSignal(rid) {
-    const promise = core.opAsync("op_signal_poll", rid);
-    core.unrefOp(promise[SymbolFor("Deno.core.internalPromiseId")]);
-    return promise;
-  }
+function pollSignal(rid) {
+  const promise = core.opAsync("op_signal_poll", rid);
+  core.unrefOp(promise[SymbolFor("Deno.core.internalPromiseId")]);
+  return promise;
+}
 
-  function unbindSignal(rid) {
-    ops.op_signal_unbind(rid);
-  }
+function unbindSignal(rid) {
+  ops.op_signal_unbind(rid);
+}
 
-  // Stores signal listeners and resource data. This has type of
-  // `Record<string, { rid: number | undefined, listeners: Set<() => void> }`
-  const signalData = {};
+// Stores signal listeners and resource data. This has type of
+// `Record<string, { rid: number | undefined, listeners: Set<() => void> }`
+const signalData = {};
 
-  /** Gets the signal handlers and resource data of the given signal */
-  function getSignalData(signo) {
-    return signalData[signo] ??
-      (signalData[signo] = { rid: undefined, listeners: new Set() });
-  }
+/** Gets the signal handlers and resource data of the given signal */
+function getSignalData(signo) {
+  return signalData[signo] ??
+    (signalData[signo] = { rid: undefined, listeners: new Set() });
+}
 
-  function checkSignalListenerType(listener) {
-    if (typeof listener !== "function") {
-      throw new TypeError(
-        `Signal listener must be a function. "${typeof listener}" is given.`,
-      );
-    }
+function checkSignalListenerType(listener) {
+  if (typeof listener !== "function") {
+    throw new TypeError(
+      `Signal listener must be a function. "${typeof listener}" is given.`,
+    );
   }
+}
 
-  function addSignalListener(signo, listener) {
-    checkSignalListenerType(listener);
+function addSignalListener(signo, listener) {
+  checkSignalListenerType(listener);
 
-    const sigData = getSignalData(signo);
-    sigData.listeners.add(listener);
+  const sigData = getSignalData(signo);
+  sigData.listeners.add(listener);
 
-    if (!sigData.rid) {
-      // If signal resource doesn't exist, create it.
-      // The program starts listening to the signal
-      sigData.rid = bindSignal(signo);
-      loop(sigData);
-    }
+  if (!sigData.rid) {
+    // If signal resource doesn't exist, create it.
+    // The program starts listening to the signal
+    sigData.rid = bindSignal(signo);
+    loop(sigData);
   }
+}
 
-  function removeSignalListener(signo, listener) {
-    checkSignalListenerType(listener);
+function removeSignalListener(signo, listener) {
+  checkSignalListenerType(listener);
 
-    const sigData = getSignalData(signo);
-    SetPrototypeDelete(sigData.listeners, listener);
+  const sigData = getSignalData(signo);
+  SetPrototypeDelete(sigData.listeners, listener);
 
-    if (sigData.listeners.size === 0 && sigData.rid) {
-      unbindSignal(sigData.rid);
-      sigData.rid = undefined;
-    }
+  if (sigData.listeners.size === 0 && sigData.rid) {
+    unbindSignal(sigData.rid);
+    sigData.rid = undefined;
   }
+}
 
-  async function loop(sigData) {
-    while (sigData.rid) {
-      if (await pollSignal(sigData.rid)) {
-        return;
-      }
-      for (const listener of new SafeSetIterator(sigData.listeners)) {
-        listener();
-      }
+async function loop(sigData) {
+  while (sigData.rid) {
+    if (await pollSignal(sigData.rid)) {
+      return;
+    }
+    for (const listener of new SafeSetIterator(sigData.listeners)) {
+      listener();
     }
   }
+}
 
-  window.__bootstrap.signals = {
-    addSignalListener,
-    removeSignalListener,
-  };
-})(this);
+export { addSignalListener, removeSignalListener };