Process source maps in Rust instead of JS (#1280)

- Improves speed and binary size significantly.
- Makes deno_last_exception() output a JSON structure.
- Isolate::execute and Isolate::event_loop now return
  structured, mapped JSError objects on errors.
- Removes libdeno functions:
  libdeno.setGlobalErrorHandler()
  libdeno.setPromiseRejectHandler()
  libdeno.setPromiseErrorExaminer()

In collaboration with Ryan Dahl.

1 files changed, 20 insertions, 0 deletions

diff --git a/src/deno_dir.rs b/src/deno_dir.rs
index 8f13fd843..a6a741ec1 100644
--- a/src/deno_dir.rs
+++ b/src/deno_dir.rs
@@ -5,7 +5,9 @@ use errors::DenoResult;
 use errors::ErrorKind;
 use fs as deno_fs;
 use http_util;
+use js_errors::SourceMapGetter;
 use msg;
+
 use ring;
 use std;
 use std::fmt::Write;
@@ -346,6 +348,24 @@ impl DenoDir {
   }
 }
 
+impl SourceMapGetter for DenoDir {
+  fn get_source_map(&self, script_name: &str) -> Option<String> {
+    match self.code_fetch(script_name, ".") {
+      Err(_e) => {
+        return None;
+      }
+      Ok(out) => match out.maybe_source_map {
+        None => {
+          return None;
+        }
+        Some(source_map) => {
+          return Some(source_map);
+        }
+      },
+    }
+  }
+}
+
 fn get_cache_filename(basedir: &Path, url: &Url) -> PathBuf {
   let host = url.host_str().unwrap();
   let host_port = match url.port() {