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|
use insta::assert_snapshot;
use super::{infer_with_mismatches, type_at};
#[test]
fn infer_never1() {
let t = type_at(
r#"
//- /main.rs
fn test() {
let t = return;
t<|>;
}
"#,
);
assert_eq!(t, "!");
}
#[test]
fn infer_never2() {
let t = type_at(
r#"
//- /main.rs
fn gen<T>() -> T { loop {} }
fn test() {
let a = gen();
if false { a } else { loop {} };
a<|>;
}
"#,
);
assert_eq!(t, "!");
}
#[test]
fn infer_never3() {
let t = type_at(
r#"
//- /main.rs
fn gen<T>() -> T { loop {} }
fn test() {
let a = gen();
if false { loop {} } else { a };
a<|>;
}
"#,
);
assert_eq!(t, "!");
}
#[test]
fn never_type_in_generic_args() {
let t = type_at(
r#"
//- /main.rs
enum Option<T> { None, Some(T) }
fn test() {
let a = if true { Option::None } else { Option::Some(return) };
a<|>;
}
"#,
);
assert_eq!(t, "Option<!>");
}
#[test]
fn never_type_can_be_reinferred1() {
let t = type_at(
r#"
//- /main.rs
fn gen<T>() -> T { loop {} }
fn test() {
let a = gen();
if false { loop {} } else { a };
a<|>;
if false { a };
}
"#,
);
assert_eq!(t, "()");
}
#[test]
fn never_type_can_be_reinferred2() {
let t = type_at(
r#"
//- /main.rs
enum Option<T> { None, Some(T) }
fn test() {
let a = if true { Option::None } else { Option::Some(return) };
a<|>;
match 42 {
42 => a,
_ => Option::Some(42),
};
}
"#,
);
assert_eq!(t, "Option<i32>");
}
#[test]
fn never_type_can_be_reinferred3() {
let t = type_at(
r#"
//- /main.rs
enum Option<T> { None, Some(T) }
fn test() {
let a = if true { Option::None } else { Option::Some(return) };
a<|>;
match 42 {
42 => a,
_ => Option::Some("str"),
};
}
"#,
);
assert_eq!(t, "Option<&str>");
}
#[test]
fn match_no_arm() {
let t = type_at(
r#"
//- /main.rs
enum Void {}
fn test(a: Void) {
let t = match a {};
t<|>;
}
"#,
);
assert_eq!(t, "!");
}
#[test]
fn match_unknown_arm() {
let t = type_at(
r#"
//- /main.rs
fn test(a: Option) {
let t = match 0 {
_ => unknown,
};
t<|>;
}
"#,
);
assert_eq!(t, "{unknown}");
}
#[test]
fn if_never() {
let t = type_at(
r#"
//- /main.rs
fn test() {
let i = if true {
loop {}
} else {
3.0
};
i<|>;
}
"#,
);
assert_eq!(t, "f64");
}
#[test]
fn if_else_never() {
let t = type_at(
r#"
//- /main.rs
fn test(input: bool) {
let i = if input {
2.0
} else {
return
};
i<|>;
}
"#,
);
assert_eq!(t, "f64");
}
#[test]
fn match_first_arm_never() {
let t = type_at(
r#"
//- /main.rs
fn test(a: i32) {
let i = match a {
1 => return,
2 => 2.0,
3 => loop {},
_ => 3.0,
};
i<|>;
}
"#,
);
assert_eq!(t, "f64");
}
#[test]
fn match_second_arm_never() {
let t = type_at(
r#"
//- /main.rs
fn test(a: i32) {
let i = match a {
1 => 3.0,
2 => loop {},
3 => 3.0,
_ => return,
};
i<|>;
}
"#,
);
assert_eq!(t, "f64");
}
#[test]
fn match_all_arms_never() {
let t = type_at(
r#"
//- /main.rs
fn test(a: i32) {
let i = match a {
2 => return,
_ => loop {},
};
i<|>;
}
"#,
);
assert_eq!(t, "!");
}
#[test]
fn match_no_never_arms() {
let t = type_at(
r#"
//- /main.rs
fn test(a: i32) {
let i = match a {
2 => 2.0,
_ => 3.0,
};
i<|>;
}
"#,
);
assert_eq!(t, "f64");
}
#[test]
fn diverging_expression_1() {
let t = infer_with_mismatches(
r#"
//- /main.rs
fn test1() {
let x: u32 = return;
}
fn test2() {
let x: u32 = { return; };
}
fn test3() {
let x: u32 = loop {};
}
fn test4() {
let x: u32 = { loop {} };
}
fn test5() {
let x: u32 = { if true { loop {}; } else { loop {}; } };
}
fn test6() {
let x: u32 = { let y: u32 = { loop {}; }; };
}
"#,
true,
);
assert_snapshot!(t, @r###"
25..53 '{ ...urn; }': ()
35..36 'x': u32
44..50 'return': !
65..98 '{ ...; }; }': ()
75..76 'x': u32
84..95 '{ return; }': u32
86..92 'return': !
110..139 '{ ... {}; }': ()
120..121 'x': u32
129..136 'loop {}': !
134..136 '{}': ()
151..184 '{ ...} }; }': ()
161..162 'x': u32
170..181 '{ loop {} }': u32
172..179 'loop {}': !
177..179 '{}': ()
196..260 '{ ...} }; }': ()
206..207 'x': u32
215..257 '{ if t...}; } }': u32
217..255 'if tru... {}; }': u32
220..224 'true': bool
225..237 '{ loop {}; }': u32
227..234 'loop {}': !
232..234 '{}': ()
243..255 '{ loop {}; }': u32
245..252 'loop {}': !
250..252 '{}': ()
272..324 '{ ...; }; }': ()
282..283 'x': u32
291..321 '{ let ...; }; }': u32
297..298 'y': u32
306..318 '{ loop {}; }': u32
308..315 'loop {}': !
313..315 '{}': ()
"###);
}
#[test]
fn diverging_expression_2() {
let t = infer_with_mismatches(
r#"
//- /main.rs
fn test1() {
// should give type mismatch
let x: u32 = { loop {}; "foo" };
}
"#,
true,
);
assert_snapshot!(t, @r###"
25..98 '{ ..." }; }': ()
68..69 'x': u32
77..95 '{ loop...foo" }': &str
79..86 'loop {}': !
84..86 '{}': ()
88..93 '"foo"': &str
77..95: expected u32, got &str
88..93: expected u32, got &str
"###);
}
#[test]
fn diverging_expression_3_break() {
let t = infer_with_mismatches(
r#"
//- /main.rs
fn test1() {
// should give type mismatch
let x: u32 = { loop { break; } };
}
fn test2() {
// should give type mismatch
let x: u32 = { for a in b { break; }; };
// should give type mismatch as well
let x: u32 = { for a in b {}; };
// should give type mismatch as well
let x: u32 = { for a in b { return; }; };
}
fn test3() {
// should give type mismatch
let x: u32 = { while true { break; }; };
// should give type mismatch as well -- there's an implicit break, even if it's never hit
let x: u32 = { while true {}; };
// should give type mismatch as well
let x: u32 = { while true { return; }; };
}
"#,
true,
);
assert_snapshot!(t, @r###"
25..99 '{ ...} }; }': ()
68..69 'x': u32
77..96 '{ loop...k; } }': ()
79..94 'loop { break; }': ()
84..94 '{ break; }': ()
86..91 'break': !
77..96: expected u32, got ()
79..94: expected u32, got ()
111..357 '{ ...; }; }': ()
154..155 'x': u32
163..189 '{ for ...; }; }': ()
165..186 'for a ...eak; }': ()
169..170 'a': {unknown}
174..175 'b': {unknown}
176..186 '{ break; }': ()
178..183 'break': !
240..241 'x': u32
249..267 '{ for ... {}; }': ()
251..264 'for a in b {}': ()
255..256 'a': {unknown}
260..261 'b': {unknown}
262..264 '{}': ()
318..319 'x': u32
327..354 '{ for ...; }; }': ()
329..351 'for a ...urn; }': ()
333..334 'a': {unknown}
338..339 'b': {unknown}
340..351 '{ return; }': ()
342..348 'return': !
163..189: expected u32, got ()
249..267: expected u32, got ()
327..354: expected u32, got ()
369..668 '{ ...; }; }': ()
412..413 'x': u32
421..447 '{ whil...; }; }': ()
423..444 'while ...eak; }': ()
429..433 'true': bool
434..444 '{ break; }': ()
436..441 'break': !
551..552 'x': u32
560..578 '{ whil... {}; }': ()
562..575 'while true {}': ()
568..572 'true': bool
573..575 '{}': ()
629..630 'x': u32
638..665 '{ whil...; }; }': ()
640..662 'while ...urn; }': ()
646..650 'true': bool
651..662 '{ return; }': ()
653..659 'return': !
421..447: expected u32, got ()
560..578: expected u32, got ()
638..665: expected u32, got ()
"###);
}
|