Refactor error to use dynamic dispatch and traits

This is in preperation for dynamic import (#1789), which is more easily
implemented when errors are dynamic.

1 files changed, 10 insertions, 0 deletions

diff --git a/cli/import_map.rs b/cli/import_map.rs
index 1f136a3e9..abe9835f8 100644
--- a/cli/import_map.rs
+++ b/cli/import_map.rs
@@ -3,6 +3,8 @@ use indexmap::IndexMap;
 use serde_json::Map;
 use serde_json::Value;
 use std::cmp::Ordering;
+use std::error::Error;
+use std::fmt;
 use std::fs;
 use url::Url;
 
@@ -19,6 +21,14 @@ impl ImportMapError {
   }
 }
 
+impl fmt::Display for ImportMapError {
+  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    f.pad(&self.msg)
+  }
+}
+
+impl Error for ImportMapError {}
+
 // NOTE: here is difference between deno and reference implementation - deno currently
 //  can't resolve URL with other schemes (eg. data:, about:, blob:)
 const SUPPORTED_FETCH_SCHEMES: [&str; 3] = ["http", "https", "file"];