diff --git a/build_system/src/clean.rs b/build_system/src/clean.rs
index 56cc19d255f..929a878113d 100644
--- a/build_system/src/clean.rs
+++ b/build_system/src/clean.rs
@@ -1,40 +1,43 @@
-use crate::utils::remove_file;
+use crate::utils::{remove_file, run_command};
 
 use std::fs::remove_dir_all;
 
 #[derive(Default)]
-struct CleanArg {
-    all: bool,
+enum CleanArg {
+    /// `clean all`
+    All,
+    /// `clean ui-tests`
+    UiTests,
+    /// `clean --help`
+    #[default]
+    Help,
 }
 
 impl CleanArg {
-    fn new() -> Result<Option<Self>, String> {
-        let mut args = CleanArg::default();
-
+    fn new() -> Result<Self, String> {
         // We skip the binary and the "clean" option.
         for arg in std::env::args().skip(2) {
-            match arg.as_str() {
-                "all" => args.all = true,
-                "--help" => {
-                    Self::usage();
-                    return Ok(None);
-                }
-                a => return Err(format!("Unknown argument `{}`", a)),
-            }
+            return match arg.as_str() {
+                "all" => Ok(Self::All),
+                "ui-tests" => Ok(Self::UiTests),
+                "--help" => Ok(Self::Help),
+                a => Err(format!("Unknown argument `{}`", a)),
+            };
         }
-        Ok(Some(args))
+        Ok(Self::default())
     }
+}
 
-    fn usage() {
-        println!(
-            r#"
-    `clean` command help:
+fn usage() {
+    println!(
+        r#"
+`clean` command help:
 
-        all                      : Clean all data
-        --help                   : Show this help
-    "#
-        )
-    }
+    all                      : Clean all data
+    ui-tests                 : Clean ui tests
+    --help                   : Show this help
+"#
+    )
 }
 
 fn clean_all() -> Result<(), String> {
@@ -60,14 +63,25 @@ fn clean_all() -> Result<(), String> {
     Ok(())
 }
 
-pub fn run() -> Result<(), String> {
-    let args = match CleanArg::new()? {
-        Some(a) => a,
-        None => return Ok(()),
-    };
+fn clean_ui_tests() -> Result<(), String> {
+    run_command(
+        &[
+            &"find",
+            &"rust/build/x86_64-unknown-linux-gnu/test/ui/",
+            &"-name",
+            &"stamp",
+            &"-delete",
+        ],
+        None,
+    )?;
+    Ok(())
+}
 
-    if args.all {
-        clean_all()?;
+pub fn run() -> Result<(), String> {
+    match CleanArg::new()? {
+        CleanArg::All => clean_all()?,
+        CleanArg::UiTests => clean_ui_tests()?,
+        CleanArg::Help => usage(),
     }
     Ok(())
 }
diff --git a/build_system/src/test.rs b/build_system/src/test.rs
index 1577cbf2b53..f3d0d38499c 100644
--- a/build_system/src/test.rs
+++ b/build_system/src/test.rs
@@ -32,7 +32,6 @@ fn get_runners() -> Runners {
         ("Run failing rustc tests", test_failing_rustc),
     );
     runners.insert("--test-libcore", ("Run libcore tests", test_libcore));
-    runners.insert("--clean-ui-tests", ("Clean ui tests", clean_ui_tests));
     runners.insert("--clean", ("Empty cargo target directory", clean));
     runners.insert("--build-sysroot", ("Build sysroot", build_sysroot));
     runners.insert("--std-tests", ("Run std tests", std_tests));
@@ -1086,20 +1085,6 @@ fn test_successful_rustc(env: &Env, args: &TestArg) -> Result<(), String> {
     })
 }
 
-fn clean_ui_tests(_env: &Env, _args: &TestArg) -> Result<(), String> {
-    run_command(
-        &[
-            &"find",
-            &"rust/build/x86_64-unknown-linux-gnu/test/ui/",
-            &"-name",
-            &"stamp",
-            &"-delete",
-        ],
-        None,
-    )?;
-    Ok(())
-}
-
 fn run_all(env: &Env, args: &TestArg) -> Result<(), String> {
     clean(env, args)?;
     mini_tests(env, args)?;