diff --git a/crates/nu-cli/src/completions/command_completions.rs b/crates/nu-cli/src/completions/command_completions.rs
index 2fa7b1fa4..b9427e8e8 100644
--- a/crates/nu-cli/src/completions/command_completions.rs
+++ b/crates/nu-cli/src/completions/command_completions.rs
@@ -315,9 +315,12 @@ mod command_completions_tests {
                 working_set.render()
             };
 
-            if let Err(err) = engine_state.merge_delta(delta) {
-                assert!(false, "Merge delta has failed: {}", err);
-            }
+            let result = engine_state.merge_delta(delta);
+            assert!(
+                result.is_ok(),
+                "Merge delta has failed: {}",
+                result.err().unwrap()
+            );
 
             let is_passthrough_command = is_passthrough_command(engine_state.get_file_contents());
             assert_eq!(
diff --git a/crates/nu-cli/src/completions/completer.rs b/crates/nu-cli/src/completions/completer.rs
index 524b23e02..d1cc7fd7f 100644
--- a/crates/nu-cli/src/completions/completer.rs
+++ b/crates/nu-cli/src/completions/completer.rs
@@ -596,9 +596,12 @@ mod completer_tests {
             working_set.render()
         };
 
-        if let Err(err) = engine_state.merge_delta(delta) {
-            assert!(false, "Error merging delta: {:?}", err);
-        }
+        let result = engine_state.merge_delta(delta);
+        assert!(
+            result.is_ok(),
+            "Error merging delta: {:?}",
+            result.err().unwrap()
+        );
 
         let mut completer = NuCompleter::new(engine_state.into(), Stack::new());
         let dataset = vec![
@@ -617,7 +620,7 @@ mod completer_tests {
         for (line, has_result, begins_with, expected_values) in dataset {
             let result = completer.completion_helper(line, line.len());
             // Test whether the result is empty or not
-            assert_eq!(result.len() > 0, has_result, "line: {}", line);
+            assert_eq!(!result.is_empty(), has_result, "line: {}", line);
 
             // Test whether the result begins with the expected value
             result
@@ -629,7 +632,7 @@ mod completer_tests {
                 result
                     .iter()
                     .map(|x| expected_values.contains(&x.value.as_str()))
-                    .filter(|x| *x == true)
+                    .filter(|x| *x)
                     .count(),
                 expected_values.len(),
                 "line: {}",
diff --git a/crates/nu-command/tests/commands/cp.rs b/crates/nu-command/tests/commands/cp.rs
index 4852a1f2e..87f6bbe14 100644
--- a/crates/nu-command/tests/commands/cp.rs
+++ b/crates/nu-command/tests/commands/cp.rs
@@ -23,7 +23,7 @@ fn copies_a_file_impl(progress: bool) {
         let progress_flag = if progress { "-p" } else { "" };
 
         // Get the hash of the file content to check integrity after copy.
-        let first_hash = get_file_hash(&test_file.display());
+        let first_hash = get_file_hash(test_file.display());
 
         nu!(
             cwd: dirs.root(),
@@ -175,15 +175,15 @@ fn deep_copies_with_recursive_flag_impl(progress: bool) {
         assert!(expected_dir.exists());
         assert!(files_exist_at(
             vec![Path::new("errors.txt"), Path::new("multishells.txt")],
-            &jonathans_expected_copied_dir
+            jonathans_expected_copied_dir
         ));
         assert!(files_exist_at(
             vec![Path::new("coverage.txt"), Path::new("commands.txt")],
-            &andres_expected_copied_dir
+            andres_expected_copied_dir
         ));
         assert!(files_exist_at(
             vec![Path::new("defer-evaluation.txt")],
-            &yehudas_expected_copied_dir
+            yehudas_expected_copied_dir
         ));
     })
 }
diff --git a/crates/nu-parser/tests/test_parser.rs b/crates/nu-parser/tests/test_parser.rs
index d9758b804..f4c153479 100644
--- a/crates/nu-parser/tests/test_parser.rs
+++ b/crates/nu-parser/tests/test_parser.rs
@@ -83,7 +83,7 @@ fn test_int(
             },
         ) = &expressions[0]
         {
-            compare_rhs_binaryOp(test_tag, &expected_val, &observed_val);
+            compare_rhs_binaryOp(test_tag, &expected_val, observed_val);
         }
     }
 }