diff --git a/crates/nu-cli/tests/alias.rs b/crates/nu-cli/tests/alias.rs
index a112aae32c..78d1dd0199 100644
--- a/crates/nu-cli/tests/alias.rs
+++ b/crates/nu-cli/tests/alias.rs
@@ -10,7 +10,7 @@ fn alias_of_command_and_flags() {
 
     // Create an alias
     let alias = r#"alias ll = ls -l"#;
-    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir.clone()).is_ok());
+    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir).is_ok());
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
@@ -29,7 +29,7 @@ fn alias_of_basic_command() {
 
     // Create an alias
     let alias = r#"alias ll = ls "#;
-    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir.clone()).is_ok());
+    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir).is_ok());
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
@@ -51,7 +51,7 @@ fn alias_of_another_alias() {
     assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir.clone()).is_ok());
     // Create the second alias
     let alias = r#"alias lf = ll -f"#;
-    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir.clone()).is_ok());
+    assert!(support::merge_input(alias.as_bytes(), &mut engine, &mut stack, dir).is_ok());
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
diff --git a/crates/nu-cli/tests/file_completions.rs b/crates/nu-cli/tests/file_completions.rs
index ad8aa8e856..6e36063637 100644
--- a/crates/nu-cli/tests/file_completions.rs
+++ b/crates/nu-cli/tests/file_completions.rs
@@ -47,8 +47,8 @@ fn command_ls_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("ls ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "ls ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -79,8 +79,8 @@ fn command_open_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("open ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "open ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -112,8 +112,8 @@ fn command_rm_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("rm ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "rm ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -145,8 +145,8 @@ fn command_cp_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("cp ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "cp ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -178,8 +178,8 @@ fn command_save_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("save ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "save ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -211,8 +211,8 @@ fn command_touch_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("touch ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "touch ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
@@ -244,8 +244,8 @@ fn command_watch_completion() {
 
     let mut completer = NuCompleter::new(std::sync::Arc::new(engine), stack);
 
-    let target_dir = format!("watch ");
-    let suggestions = completer.complete(&target_dir, target_dir.len());
+    let target_dir = "watch ";
+    let suggestions = completer.complete(target_dir, target_dir.len());
 
     #[cfg(windows)]
     let expected_paths: Vec<String> = vec![
diff --git a/crates/nu-engine/src/eval.rs b/crates/nu-engine/src/eval.rs
index c7039e5200..a6f0852af3 100644
--- a/crates/nu-engine/src/eval.rs
+++ b/crates/nu-engine/src/eval.rs
@@ -1033,12 +1033,6 @@ pub fn create_scope(
                 span,
             });
 
-            cols.push("is_binary".to_string());
-            vals.push(Value::Bool {
-                val: decl.is_binary(),
-                span,
-            });
-
             cols.push("is_builtin".to_string());
             // we can only be a is_builtin or is_custom, not both
             vals.push(Value::Bool {
diff --git a/crates/nu-parser/tests/test_parser.rs b/crates/nu-parser/tests/test_parser.rs
index a09c11223b..c9bbcf94ae 100644
--- a/crates/nu-parser/tests/test_parser.rs
+++ b/crates/nu-parser/tests/test_parser.rs
@@ -986,7 +986,7 @@ mod input_types {
 
     fn add_declations(engine_state: &mut EngineState) {
         let delta = {
-            let mut working_set = StateWorkingSet::new(&engine_state);
+            let mut working_set = StateWorkingSet::new(engine_state);
             working_set.add_decl(Box::new(Let));
             working_set.add_decl(Box::new(AggCustom));
             working_set.add_decl(Box::new(GroupByCustom));
diff --git a/crates/nu-protocol/src/engine/command.rs b/crates/nu-protocol/src/engine/command.rs
index 53ca5acb85..6ccd669808 100644
--- a/crates/nu-protocol/src/engine/command.rs
+++ b/crates/nu-protocol/src/engine/command.rs
@@ -23,10 +23,6 @@ pub trait Command: Send + Sync + CommandClone {
         input: PipelineData,
     ) -> Result<PipelineData, ShellError>;
 
-    fn is_binary(&self) -> bool {
-        false
-    }
-
     fn examples(&self) -> Vec<Example> {
         Vec::new()
     }