refactor: allow to provide polyfills for Node modules from the snapshot (#17706)

This commit does preparatory work to allow snapshotting Node.js
compatibility layer, that currently lives in `std/node`. The logic was 
changed to allow loading some modules from the snapshot and 
some from the remote URL.

Additionally "module_es_shim.js" that provides exports for "node:module"
is now snapshotted.

2 files changed, 17 insertions, 16 deletions

diff --git a/cli/module_loader.rs b/cli/module_loader.rs
index 112f29170..b61b4304e 100644
--- a/cli/module_loader.rs
+++ b/cli/module_loader.rs
@@ -77,13 +77,11 @@ impl CliModuleLoader {
     specifier: &ModuleSpecifier,
     maybe_referrer: Option<ModuleSpecifier>,
   ) -> Result<ModuleCodeSource, AnyError> {
-    if specifier.as_str() == "node:module" {
-      return Ok(ModuleCodeSource {
-        code: deno_runtime::deno_node::MODULE_ES_SHIM.to_string(),
-        found_url: specifier.to_owned(),
-        media_type: MediaType::JavaScript,
-      });
-    }
+    // TODO(bartlomieju): uncomment, when all `node:` module have been
+    // snapshotted
+    // if specifier.scheme() == "node" {
+    //   unreachable!("Node built-in modules should be handled internally.");
+    // }
     let graph = self.ps.graph();
     match graph.get(specifier) {
       Some(deno_graph::Module {
diff --git a/cli/node/mod.rs b/cli/node/mod.rs
index 9ab593304..dffcb7437 100644
--- a/cli/node/mod.rs
+++ b/cli/node/mod.rs
@@ -26,6 +26,7 @@ use deno_runtime::deno_node::package_resolve;
 use deno_runtime::deno_node::path_to_declaration_path;
 use deno_runtime::deno_node::NodeModuleKind;
 use deno_runtime::deno_node::NodeModulePolyfill;
+use deno_runtime::deno_node::NodeModulePolyfillSpecifier;
 use deno_runtime::deno_node::NodePermissions;
 use deno_runtime::deno_node::NodeResolutionMode;
 use deno_runtime::deno_node::PackageJson;
@@ -133,16 +134,18 @@ fn is_builtin_node_module(specifier: &str) -> bool {
 }
 
 pub fn resolve_builtin_node_module(specifier: &str) -> Result<Url, AnyError> {
-  // NOTE(bartlomieju): `module` is special, because we don't want to use
-  // `deno_std/node/module.ts`, but instead use a special shim that we
-  // provide in `ext/node`.
-  if specifier == "module" {
-    return Ok(Url::parse("node:module").unwrap());
-  }
-
   if let Some(module) = find_builtin_node_module(specifier) {
-    let module_url = NODE_COMPAT_URL.join(module.specifier).unwrap();
-    return Ok(module_url);
+    match module.specifier {
+      // We will load the source code from the `std/node` polyfill.
+      NodeModulePolyfillSpecifier::StdNode(specifier) => {
+        let module_url = NODE_COMPAT_URL.join(specifier).unwrap();
+        return Ok(module_url);
+      }
+      // The module has already been snapshotted and is present in the binary.
+      NodeModulePolyfillSpecifier::Embedded(specifier) => {
+        return Ok(ModuleSpecifier::parse(specifier).unwrap());
+      }
+    }
   }
 
   Err(generic_error(format!(