1 files changed, 160 insertions, 0 deletions
diff --git a/cli/module_loader.rs b/cli/module_loader.rs
new file mode 100644
index 000000000..3cbcade2a
--- /dev/null
+++ b/cli/module_loader.rs
@@ -0,0 +1,160 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+
+use crate::import_map::ImportMap;
+use crate::permissions::Permissions;
+use crate::program_state::ProgramState;
+use crate::tsc::TargetLib;
+use deno_core::error::AnyError;
+use deno_core::futures::future::FutureExt;
+use deno_core::futures::Future;
+use deno_core::ModuleLoadId;
+use deno_core::ModuleLoader;
+use deno_core::ModuleSpecifier;
+use deno_core::OpState;
+use std::cell::RefCell;
+use std::pin::Pin;
+use std::rc::Rc;
+use std::str;
+use std::sync::Arc;
+
+pub struct CliModuleLoader {
+  /// When flags contains a `.import_map_path` option, the content of the
+  /// import map file will be resolved and set.
+  pub import_map: Option<ImportMap>,
+  pub target_lib: TargetLib,
+  pub is_main: bool,
+}
+
+impl CliModuleLoader {
+  pub fn new(maybe_import_map: Option<ImportMap>) -> Rc<Self> {
+    Rc::new(CliModuleLoader {
+      import_map: maybe_import_map,
+      target_lib: TargetLib::Main,
+      is_main: true,
+    })
+  }
+
+  pub fn new_for_worker() -> Rc<Self> {
+    Rc::new(CliModuleLoader {
+      import_map: None,
+      target_lib: TargetLib::Worker,
+      is_main: false,
+    })
+  }
+}
+
+impl ModuleLoader for CliModuleLoader {
+  fn resolve(
+    &self,
+    op_state: Rc<RefCell<OpState>>,
+    specifier: &str,
+    referrer: &str,
+    is_main: bool,
+  ) -> Result<ModuleSpecifier, AnyError> {
+    let program_state = {
+      let state = op_state.borrow();
+      state.borrow::<Arc<ProgramState>>().clone()
+    };
+
+    // FIXME(bartlomieju): hacky way to provide compatibility with repl
+    let referrer = if referrer.is_empty() && program_state.flags.repl {
+      "<unknown>"
+    } else {
+      referrer
+    };
+
+    if !is_main {
+      if let Some(import_map) = &self.import_map {
+        let result = import_map.resolve(specifier, referrer)?;
+        if let Some(r) = result {
+          return Ok(r);
+        }
+      }
+    }
+
+    let module_specifier =
+      ModuleSpecifier::resolve_import(specifier, referrer)?;
+
+    Ok(module_specifier)
+  }
+
+  fn load(
+    &self,
+    op_state: Rc<RefCell<OpState>>,
+    module_specifier: &ModuleSpecifier,
+    maybe_referrer: Option<ModuleSpecifier>,
+    _is_dyn_import: bool,
+  ) -> Pin<Box<deno_core::ModuleSourceFuture>> {
+    let module_specifier = module_specifier.to_owned();
+    let module_url_specified = module_specifier.to_string();
+    let program_state = {
+      let state = op_state.borrow();
+      state.borrow::<Arc<ProgramState>>().clone()
+    };
+
+    // TODO(bartlomieju): `fetch_compiled_module` should take `load_id` param
+    let fut = async move {
+      let compiled_module = program_state
+        .fetch_compiled_module(module_specifier, maybe_referrer)
+        .await?;
+      Ok(deno_core::ModuleSource {
+        // Real module name, might be different from initial specifier
+        // due to redirections.
+        code: compiled_module.code,
+        module_url_specified,
+        module_url_found: compiled_module.name,
+      })
+    };
+
+    fut.boxed_local()
+  }
+
+  fn prepare_load(
+    &self,
+    op_state: Rc<RefCell<OpState>>,
+    _load_id: ModuleLoadId,
+    module_specifier: &ModuleSpecifier,
+    maybe_referrer: Option<String>,
+    is_dyn_import: bool,
+  ) -> Pin<Box<dyn Future<Output = Result<(), AnyError>>>> {
+    let module_specifier = module_specifier.clone();
+    let target_lib = self.target_lib.clone();
+    let maybe_import_map = self.import_map.clone();
+    let state = op_state.borrow();
+
+    // Only "main" module is loaded without permission check,
+    // ie. module that is associated with "is_main" state
+    // and is not a dynamic import.
+    let permissions = if self.is_main && !is_dyn_import {
+      Permissions::allow_all()
+    } else {
+      state.borrow::<Permissions>().clone()
+    };
+    let program_state = state.borrow::<Arc<ProgramState>>().clone();
+    drop(state);
+
+    // TODO(bartlomieju): I'm not sure if it's correct to ignore
+    // bad referrer - this is the case for `Deno.core.evalContext()` where
+    // `ref_str` is `<unknown>`.
+    let maybe_referrer = if let Some(ref_str) = maybe_referrer {
+      ModuleSpecifier::resolve_url(&ref_str).ok()
+    } else {
+      None
+    };
+
+    // TODO(bartlomieju): `prepare_module_load` should take `load_id` param
+    async move {
+      program_state
+        .prepare_module_load(
+          module_specifier,
+          maybe_referrer,
+          target_lib,
+          permissions,
+          is_dyn_import,
+          maybe_import_map,
+        )
+        .await
+    }
+    .boxed_local()
+  }
+}