add regression tests for rust-lang#67144

Author: lcnr

src/test/ui/const-generics/type-dependent/issue-67144-1.rs

@@ -0,0 +1,28 @@
+// check-pass
+#![feature(const_generics)]
+#![allow(incomplete_features)]
+
+struct X;
+
+impl X {
+    pub fn getn<const N: usize>(&self) -> [u8; N] {
+        getn::<N>()
+    }
+}
+
+fn getn<const N: usize>() -> [u8; N] {
+    unsafe {
+        std::mem::zeroed()
+    }
+}
+
+fn main() {
+    // works
+    let [a,b,c] = getn::<3>();
+
+    // cannot pattern-match on an array without a fixed length
+    let [a,b,c] = X.getn::<3>();
+
+    // mismatched types, expected array `[u8; 3]` found array `[u8; _]`
+    let arr: [u8; 3] = X.getn::<3>();
+}

src/test/ui/const-generics/type-dependent/issue-67144-2.rs

@@ -0,0 +1,22 @@
+// check-pass
+#![feature(const_generics)]
+#![allow(incomplete_features)]
+
+struct A<const N: usize>;
+
+struct X;
+
+impl X {
+    fn inner<const N: usize>() -> A<N> {
+        outer::<N>()
+    }
+}
+
+fn outer<const N: usize>() -> A<N> {
+    A
+}
+
+fn main() {
+    let i: A<3usize> = outer::<3usize>();
+    let o: A<3usize> = X::inner::<3usize>();
+}