diff --git a/tests/ui/src/imag.rs b/tests/ui/src/imag.rs
index 094a0dfe..3c517ce2 100644
--- a/tests/ui/src/imag.rs
+++ b/tests/ui/src/imag.rs
@@ -42,7 +42,7 @@ pub fn binary(tempdir: &TempDir, binary_name: &str) -> Command {
 /// Run the passed command and get the stdout of it.
 ///
 /// This function does _not_ ensure that stdin is inherited.
-pub fn stdout_of_command(command: Command) -> Vec<String> {
+pub fn stdout_of_command(mut command: Command) -> Vec<String> {
     let assert = command.assert();
     let lines = String::from_utf8(assert.get_output().stdout.clone())
         .unwrap()
diff --git a/tests/ui/src/imag_ids.rs b/tests/ui/src/imag_ids.rs
index 2c38906e..f6351eb6 100644
--- a/tests/ui/src/imag_ids.rs
+++ b/tests/ui/src/imag_ids.rs
@@ -29,15 +29,7 @@ pub fn call(tempdir: &TempDir) -> Vec<String> {
 
     // ensure that stdin is not used by the child process
     binary.stdin(std::process::Stdio::inherit());
-
-    let assert = binary.assert();
-    let lines = String::from_utf8(assert.get_output().stdout.clone())
-        .unwrap()
-        .lines()
-        .map(String::from)
-        .collect();
-    assert.success();
-    lines
+    crate::imag::stdout_of_command(binary)
 }
 
 pub fn binary(tempdir: &TempDir) -> Command {