now has error fixed

src/lib/shell/variables.rs

@@ -82,10 +82,14 @@ impl Variables {
 
     /// Create a new scope. If namespace is true, variables won't be droppable across the scope
     /// boundary
-    pub fn new_scope(&mut self, namespace: bool) { self.0.new_scope(namespace) }
+    pub fn new_scope(&mut self, namespace: bool) {
+        self.0.new_scope(namespace)
+    }
 
     /// Exit the current scope
-    pub fn pop_scope(&mut self) { self.0.pop_scope() }
+    pub fn pop_scope(&mut self) {
+        self.0.pop_scope()
+    }
 
     pub(crate) fn pop_scopes<'b>(
         &'b mut self,
@@ -196,9 +200,10 @@ impl Variables {
                     .map_err(|cause| Error::InvalidHex(variable.into(), cause))?;
                 Ok((c as char).to_string().into())
             }
-            Some(("env", variable)) => {
-                env::var(variable).map(Into::into).map_err(|_| Error::UnknownEnv(variable.into()))
-            }
+            Some(("env", variable)) => match env::var(variable) {
+                Ok(v) => Ok(v.into()),
+                Err(_) => Ok("".into()),
+            },
             Some(("super", _)) | Some(("global", _)) | None => {
                 // Otherwise, it's just a simple variable name.
                 match self.get(name) {
@@ -293,7 +298,9 @@ pub(crate) mod tests {
     impl Expander for VariableExpander {
         type Error = IonError;
 
-        fn string(&self, var: &str) -> Result<types::Str, IonError> { self.0.get_str(var) }
+        fn string(&self, var: &str) -> Result<types::Str, IonError> {
+            self.0.get_str(var)
+        }
 
         fn array(
             &self,
@@ -311,7 +318,9 @@ pub(crate) mod tests {
             Ok(cmd.into())
         }
 
-        fn tilde(&self, input: &str) -> Result<types::Str, Self::Error> { Ok(input.into()) }
+        fn tilde(&self, input: &str) -> Result<types::Str, Self::Error> {
+            Ok(input.into())
+        }
 
         fn map_keys(&self, _name: &str) -> Result<types::Args, Self::Error> {
             Err(expansion::Error::VarNotFound)