2 files changed, 99 insertions, 28 deletions

diff --git a/src/deno_dir.rs b/src/deno_dir.rs
index cb769fb86..1e369b40f 100644
--- a/src/deno_dir.rs
+++ b/src/deno_dir.rs
@@ -133,19 +133,41 @@ impl DenoDir {
     self: &DenoDir,
     module_name: &str,
     filename: &str,
-  ) -> DenoResult<String> {
-    if is_remote(module_name) {
-      self.fetch_remote_source(module_name, filename)
-    } else if module_name.starts_with(ASSET_PREFIX) {
+  ) -> DenoResult<CodeFetchOutput> {
+    if module_name.starts_with(ASSET_PREFIX) {
       panic!("Asset resolution should be done in JS, not Rust.");
-    } else {
-      assert_eq!(
-        module_name, filename,
-        "if a module isn't remote, it should have the same filename"
-      );
-      let src = fs::read_to_string(Path::new(filename))?;
-      Ok(src)
     }
+    let is_module_remote = is_remote(module_name);
+    let use_extension = |ext| {
+      let module_name = format!("{}{}", module_name, ext);
+      let filename = format!("{}{}", filename, ext);
+      let source_code = if is_module_remote {
+        self.fetch_remote_source(&module_name, &filename)?
+      } else {
+        assert_eq!(
+          module_name, filename,
+          "if a module isn't remote, it should have the same filename"
+        );
+        fs::read_to_string(Path::new(&filename))?
+      };
+      return Ok(CodeFetchOutput {
+        module_name: module_name.to_string(),
+        filename: filename.to_string(),
+        source_code,
+        maybe_output_code: None,
+      });
+    };
+    let default_attempt = use_extension("");
+    if default_attempt.is_ok() {
+      return default_attempt;
+    }
+    debug!("Trying {}.ts...", module_name);
+    let ts_attempt = use_extension(".ts");
+    if ts_attempt.is_ok() {
+      return ts_attempt;
+    }
+    debug!("Trying {}.js...", module_name);
+    use_extension(".js")
   }
 
   pub fn code_fetch(
@@ -161,16 +183,7 @@ impl DenoDir {
     let (module_name, filename) =
       self.resolve_module(module_specifier, containing_file)?;
 
-    let result = self
-      .get_source_code(module_name.as_str(), filename.as_str())
-      .and_then(|source_code| {
-        Ok(CodeFetchOutput {
-          module_name,
-          filename,
-          source_code,
-          maybe_output_code: None,
-        })
-      });
+    let result = self.get_source_code(module_name.as_str(), filename.as_str());
     let out = match result {
       Err(err) => {
         if err.kind() == ErrorKind::NotFound {
@@ -421,6 +434,48 @@ fn test_code_fetch() {
 }
 
 #[test]
+fn test_code_fetch_no_ext() {
+  let (_temp_dir, deno_dir) = test_setup();
+
+  let cwd = std::env::current_dir().unwrap();
+  let cwd_string = String::from(cwd.to_str().unwrap()) + "/";
+
+  // Assuming cwd is the deno repo root.
+  let module_specifier = "./js/main";
+  let containing_file = cwd_string.as_str();
+  let r = deno_dir.code_fetch(module_specifier, containing_file);
+  assert!(r.is_ok());
+
+  // Test .ts extension
+  // Assuming cwd is the deno repo root.
+  let module_specifier = "./js/main";
+  let containing_file = cwd_string.as_str();
+  let r = deno_dir.code_fetch(module_specifier, containing_file);
+  assert!(r.is_ok());
+  let code_fetch_output = r.unwrap();
+  // could only test .ends_with to avoid include local abs path
+  assert!(code_fetch_output.module_name.ends_with("/js/main.ts"));
+  assert!(code_fetch_output.filename.ends_with("/js/main.ts"));
+  assert!(code_fetch_output.source_code.len() > 10);
+
+  // Test .js extension
+  // Assuming cwd is the deno repo root.
+  let module_specifier = "./js/mock_builtin";
+  let containing_file = cwd_string.as_str();
+  let r = deno_dir.code_fetch(module_specifier, containing_file);
+  assert!(r.is_ok());
+  let code_fetch_output = r.unwrap();
+  // could only test .ends_with to avoid include local abs path
+  assert!(
+    code_fetch_output
+      .module_name
+      .ends_with("/js/mock_builtin.js")
+  );
+  assert!(code_fetch_output.filename.ends_with("/js/mock_builtin.js"));
+  assert!(code_fetch_output.source_code.len() > 10);
+}
+
+#[test]
 fn test_src_file_to_url_1() {
   let (_temp_dir, deno_dir) = test_setup();
   assert_eq!("hello", deno_dir.src_file_to_url("hello"));
diff --git a/src/http.rs b/src/http.rs
index 5f78cf232..9ef9adb8f 100644
--- a/src/http.rs
+++ b/src/http.rs
@@ -1,10 +1,12 @@
 // Copyright 2018 the Deno authors. All rights reserved. MIT license.
 
-use errors::DenoResult;
+use errors;
+use errors::{DenoError, DenoResult};
 use tokio_util;
 
-use futures::Future;
-use futures::Stream;
+use futures;
+use futures::future::Either;
+use futures::{Future, Stream};
 use hyper;
 use hyper::client::Client;
 use hyper::client::HttpConnector;
@@ -31,11 +33,25 @@ pub fn get_client() -> Client<Connector, hyper::Body> {
 pub fn fetch_sync_string(module_name: &str) -> DenoResult<String> {
   let url = module_name.parse::<Uri>().unwrap();
   let client = get_client();
-  let future = client
+  let fetch_future = client
     .get(url)
-    .and_then(|response| response.into_body().concat2());
-  let body = tokio_util::block_on(future)?;
-  Ok(String::from_utf8(body.to_vec()).unwrap())
+    .map_err(|err| DenoError::from(err))
+    .and_then(|response| {
+      if !response.status().is_success() {
+        return Either::A(futures::future::err(errors::new(
+          errors::ErrorKind::NotFound,
+          "module not found".to_string(),
+        )));
+      }
+      Either::B(
+        response
+          .into_body()
+          .concat2()
+          .map(|body| String::from_utf8(body.to_vec()).unwrap())
+          .map_err(|err| DenoError::from(err)),
+      )
+    });
+  tokio_util::block_on(fetch_future)
 }
 
 /* TODO(ry) Re-enabled this test. Disabling to work around bug in #782.