1 files changed, 185 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/trailing_empty_array.rs b/src/tools/clippy/tests/ui/trailing_empty_array.rs
new file mode 100644
index 000000000..c39b0bcaf
--- /dev/null
+++ b/src/tools/clippy/tests/ui/trailing_empty_array.rs
@@ -0,0 +1,185 @@
+#![warn(clippy::trailing_empty_array)]
+
+// Do lint:
+
+struct RarelyUseful {
+    field: i32,
+    last: [usize; 0],
+}
+
+struct OnlyField {
+    first_and_last: [usize; 0],
+}
+
+struct GenericArrayType<T> {
+    field: i32,
+    last: [T; 0],
+}
+
+#[must_use]
+struct OnlyAnotherAttribute {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[derive(Debug)]
+struct OnlyADeriveAttribute {
+    field: i32,
+    last: [usize; 0],
+}
+
+const ZERO: usize = 0;
+struct ZeroSizedWithConst {
+    field: i32,
+    last: [usize; ZERO],
+}
+
+#[allow(clippy::eq_op)]
+const fn compute_zero() -> usize {
+    (4 + 6) - (2 * 5)
+}
+struct ZeroSizedWithConstFunction {
+    field: i32,
+    last: [usize; compute_zero()],
+}
+
+const fn compute_zero_from_arg(x: usize) -> usize {
+    x - 1
+}
+struct ZeroSizedWithConstFunction2 {
+    field: i32,
+    last: [usize; compute_zero_from_arg(1)],
+}
+
+struct ZeroSizedArrayWrapper([usize; 0]);
+
+struct TupleStruct(i32, [usize; 0]);
+
+struct LotsOfFields {
+    f1: u32,
+    f2: u32,
+    f3: u32,
+    f4: u32,
+    f5: u32,
+    f6: u32,
+    f7: u32,
+    f8: u32,
+    f9: u32,
+    f10: u32,
+    f11: u32,
+    f12: u32,
+    f13: u32,
+    f14: u32,
+    f15: u32,
+    f16: u32,
+    last: [usize; 0],
+}
+
+// Don't lint
+
+#[repr(C)]
+struct GoodReason {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[repr(C)]
+struct OnlyFieldWithReprC {
+    first_and_last: [usize; 0],
+}
+
+struct NonZeroSizedArray {
+    field: i32,
+    last: [usize; 1],
+}
+
+struct NotLastField {
+    f1: u32,
+    zero_sized: [usize; 0],
+    last: i32,
+}
+
+const ONE: usize = 1;
+struct NonZeroSizedWithConst {
+    field: i32,
+    last: [usize; ONE],
+}
+
+#[derive(Debug)]
+#[repr(C)]
+struct AlsoADeriveAttribute {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[must_use]
+#[repr(C)]
+struct AlsoAnotherAttribute {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[repr(packed)]
+struct ReprPacked {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[repr(C, packed)]
+struct ReprCPacked {
+    field: i32,
+    last: [usize; 0],
+}
+
+#[repr(align(64))]
+struct ReprAlign {
+    field: i32,
+    last: [usize; 0],
+}
+#[repr(C, align(64))]
+struct ReprCAlign {
+    field: i32,
+    last: [usize; 0],
+}
+
+// NOTE: because of https://doc.rust-lang.org/stable/reference/type-layout.html#primitive-representation-of-enums-with-fields and I'm not sure when in the compilation pipeline that would happen
+#[repr(C)]
+enum DontLintAnonymousStructsFromDesuraging {
+    A(u32),
+    B(f32, [u64; 0]),
+    C { x: u32, y: [u64; 0] },
+}
+
+#[repr(C)]
+struct TupleStructReprC(i32, [usize; 0]);
+
+type NamedTuple = (i32, [usize; 0]);
+
+#[rustfmt::skip] // [rustfmt#4995](https://github.com/rust-lang/rustfmt/issues/4995)
+struct ConstParamZeroDefault<const N: usize = 0> {
+    field: i32,
+    last: [usize; N],
+}
+
+struct ConstParamNoDefault<const N: usize> {
+    field: i32,
+    last: [usize; N],
+}
+
+#[rustfmt::skip] 
+struct ConstParamNonZeroDefault<const N: usize = 1> {
+    field: i32,
+    last: [usize; N],
+}
+
+struct TwoGenericParams<T, const N: usize> {
+    field: i32,
+    last: [T; N],
+}
+
+type A = ConstParamZeroDefault;
+type B = ConstParamZeroDefault<0>;
+type C = ConstParamNoDefault<0>;
+type D = ConstParamNonZeroDefault<0>;
+
+fn main() {}