1 files changed, 55 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/vec.rs b/src/tools/clippy/tests/ui/vec.rs
new file mode 100644
index 00000000000..3eb960f53d7
--- /dev/null
+++ b/src/tools/clippy/tests/ui/vec.rs
@@ -0,0 +1,55 @@
+// run-rustfix
+
+#![warn(clippy::useless_vec)]
+
+#[derive(Debug)]
+struct NonCopy;
+
+fn on_slice(_: &[u8]) {}
+#[allow(clippy::ptr_arg)]
+fn on_vec(_: &Vec<u8>) {}
+
+struct Line {
+    length: usize,
+}
+
+impl Line {
+    fn length(&self) -> usize {
+        self.length
+    }
+}
+
+fn main() {
+    on_slice(&vec![]);
+    on_slice(&[]);
+
+    on_slice(&vec![1, 2]);
+    on_slice(&[1, 2]);
+
+    on_slice(&vec![1, 2]);
+    on_slice(&[1, 2]);
+    #[rustfmt::skip]
+    on_slice(&vec!(1, 2));
+    on_slice(&[1, 2]);
+
+    on_slice(&vec![1; 2]);
+    on_slice(&[1; 2]);
+
+    on_vec(&vec![]);
+    on_vec(&vec![1, 2]);
+    on_vec(&vec![1; 2]);
+
+    // Now with non-constant expressions
+    let line = Line { length: 2 };
+
+    on_slice(&vec![2; line.length]);
+    on_slice(&vec![2; line.length()]);
+
+    for a in vec![1, 2, 3] {
+        println!("{:?}", a);
+    }
+
+    for a in vec![NonCopy, NonCopy] {
+        println!("{:?}", a);
+    }
+}