1 files changed, 104 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/expect_fun_call.rs b/src/tools/clippy/tests/ui/expect_fun_call.rs
new file mode 100644
index 000000000..22e530b80
--- /dev/null
+++ b/src/tools/clippy/tests/ui/expect_fun_call.rs
@@ -0,0 +1,104 @@
+// run-rustfix
+
+#![warn(clippy::expect_fun_call)]
+#![allow(clippy::to_string_in_format_args)]
+
+/// Checks implementation of the `EXPECT_FUN_CALL` lint
+
+macro_rules! one {
+    () => {
+        1
+    };
+}
+
+fn main() {
+    struct Foo;
+
+    impl Foo {
+        fn new() -> Self {
+            Foo
+        }
+
+        fn expect(&self, msg: &str) {
+            panic!("{}", msg)
+        }
+    }
+
+    let with_some = Some("value");
+    with_some.expect("error");
+
+    let with_none: Option<i32> = None;
+    with_none.expect("error");
+
+    let error_code = 123_i32;
+    let with_none_and_format: Option<i32> = None;
+    with_none_and_format.expect(&format!("Error {}: fake error", error_code));
+
+    let with_none_and_as_str: Option<i32> = None;
+    with_none_and_as_str.expect(format!("Error {}: fake error", error_code).as_str());
+
+    let with_none_and_format_with_macro: Option<i32> = None;
+    with_none_and_format_with_macro.expect(format!("Error {}: fake error", one!()).as_str());
+
+    let with_ok: Result<(), ()> = Ok(());
+    with_ok.expect("error");
+
+    let with_err: Result<(), ()> = Err(());
+    with_err.expect("error");
+
+    let error_code = 123_i32;
+    let with_err_and_format: Result<(), ()> = Err(());
+    with_err_and_format.expect(&format!("Error {}: fake error", error_code));
+
+    let with_err_and_as_str: Result<(), ()> = Err(());
+    with_err_and_as_str.expect(format!("Error {}: fake error", error_code).as_str());
+
+    let with_dummy_type = Foo::new();
+    with_dummy_type.expect("another test string");
+
+    let with_dummy_type_and_format = Foo::new();
+    with_dummy_type_and_format.expect(&format!("Error {}: fake error", error_code));
+
+    let with_dummy_type_and_as_str = Foo::new();
+    with_dummy_type_and_as_str.expect(format!("Error {}: fake error", error_code).as_str());
+
+    //Issue #2937
+    Some("foo").expect(format!("{} {}", 1, 2).as_ref());
+
+    //Issue #2979 - this should not lint
+    {
+        let msg = "bar";
+        Some("foo").expect(msg);
+    }
+
+    {
+        fn get_string() -> String {
+            "foo".to_string()
+        }
+
+        fn get_static_str() -> &'static str {
+            "foo"
+        }
+
+        fn get_non_static_str(_: &u32) -> &str {
+            "foo"
+        }
+
+        Some("foo").expect(&get_string());
+        Some("foo").expect(get_string().as_ref());
+        Some("foo").expect(get_string().as_str());
+
+        Some("foo").expect(get_static_str());
+        Some("foo").expect(get_non_static_str(&0));
+    }
+
+    //Issue #3839
+    Some(true).expect(&format!("key {}, {}", 1, 2));
+
+    //Issue #4912 - the receiver is a &Option
+    {
+        let opt = Some(1);
+        let opt_ref = &opt;
+        opt_ref.expect(&format!("{:?}", opt_ref));
+    }
+}