1 files changed, 93 insertions, 0 deletions
diff --git a/tests/ui/lint/invalid_from_utf8.rs b/tests/ui/lint/invalid_from_utf8.rs
new file mode 100644
index 000000000..9c8c63681
--- /dev/null
+++ b/tests/ui/lint/invalid_from_utf8.rs
@@ -0,0 +1,93 @@
+// check-pass
+
+#![feature(concat_bytes)]
+#![warn(invalid_from_utf8_unchecked)]
+#![warn(invalid_from_utf8)]
+
+pub fn from_utf8_unchecked_mut() {
+    // Valid
+    unsafe {
+        std::str::from_utf8_unchecked_mut(&mut [99, 108, 105, 112, 112, 121]);
+        std::str::from_utf8_unchecked_mut(&mut [b'c', b'l', b'i', b'p', b'p', b'y']);
+
+        let x = 0xA0;
+        std::str::from_utf8_unchecked_mut(&mut [0xC0, x]);
+    }
+
+    // Invalid
+    unsafe {
+        std::str::from_utf8_unchecked_mut(&mut [99, 108, 130, 105, 112, 112, 121]);
+        //~^ WARN calls to `std::str::from_utf8_unchecked_mut`
+        std::str::from_utf8_unchecked_mut(&mut [b'c', b'l', b'\x82', b'i', b'p', b'p', b'y']);
+        //~^ WARN calls to `std::str::from_utf8_unchecked_mut`
+    }
+}
+
+pub fn from_utf8_unchecked() {
+    // Valid
+    unsafe {
+        std::str::from_utf8_unchecked(&[99, 108, 105, 112, 112, 121]);
+        std::str::from_utf8_unchecked(&[b'c', b'l', b'i', b'p', b'p', b'y']);
+        std::str::from_utf8_unchecked(b"clippy");
+
+        let x = 0xA0;
+        std::str::from_utf8_unchecked(&[0xC0, x]);
+    }
+
+    // Invalid
+    unsafe {
+        std::str::from_utf8_unchecked(&[99, 108, 130, 105, 112, 112, 121]);
+        //~^ WARN calls to `std::str::from_utf8_unchecked`
+        std::str::from_utf8_unchecked(&[b'c', b'l', b'\x82', b'i', b'p', b'p', b'y']);
+        //~^ WARN calls to `std::str::from_utf8_unchecked`
+        std::str::from_utf8_unchecked(b"cl\x82ippy");
+        //~^ WARN calls to `std::str::from_utf8_unchecked`
+        std::str::from_utf8_unchecked(concat_bytes!(b"cl", b"\x82ippy"));
+        //~^ WARN calls to `std::str::from_utf8_unchecked`
+    }
+}
+
+pub fn from_utf8_mut() {
+    // Valid
+    {
+        std::str::from_utf8_mut(&mut [99, 108, 105, 112, 112, 121]);
+        std::str::from_utf8_mut(&mut [b'c', b'l', b'i', b'p', b'p', b'y']);
+
+        let x = 0xa0;
+        std::str::from_utf8_mut(&mut [0xc0, x]);
+    }
+
+    // Invalid
+    {
+        std::str::from_utf8_mut(&mut [99, 108, 130, 105, 112, 112, 121]);
+        //~^ WARN calls to `std::str::from_utf8_mut`
+        std::str::from_utf8_mut(&mut [b'c', b'l', b'\x82', b'i', b'p', b'p', b'y']);
+        //~^ WARN calls to `std::str::from_utf8_mut`
+    }
+}
+
+pub fn from_utf8() {
+    // Valid
+    {
+        std::str::from_utf8(&[99, 108, 105, 112, 112, 121]);
+        std::str::from_utf8(&[b'c', b'l', b'i', b'p', b'p', b'y']);
+        std::str::from_utf8(b"clippy");
+
+        let x = 0xA0;
+        std::str::from_utf8(&[0xC0, x]);
+    }
+
+    // Invalid
+    {
+        std::str::from_utf8(&[99, 108, 130, 105, 112, 112, 121]);
+        //~^ WARN calls to `std::str::from_utf8`
+        std::str::from_utf8(&[b'c', b'l', b'\x82', b'i', b'p', b'p', b'y']);
+        //~^ WARN calls to `std::str::from_utf8`
+        std::str::from_utf8(b"cl\x82ippy");
+        //~^ WARN calls to `std::str::from_utf8`
+        std::str::from_utf8(concat_bytes!(b"cl", b"\x82ippy"));
+        //~^ WARN calls to `std::str::from_utf8`
+    }
+}
+
+fn main() {}