path: root/crates/ra_hir_ty/src/tests/patterns.rs

use insta::assert_snapshot;
use test_utils::mark;

use super::{infer, infer_with_mismatches};

#[test]
fn infer_pattern() {
    assert_snapshot!(
        infer(r#"
fn test(x: &i32) {
    let y = x;
    let &z = x;
    let a = z;
    let (c, d) = (1, "hello");

    for (e, f) in some_iter {
        let g = e;
    }

    if let [val] = opt {
        let h = val;
    }

    let lambda = |a: u64, b, c: i32| { a + b; c };

    let ref ref_to_x = x;
    let mut mut_x = x;
    let ref mut mut_ref_to_x = x;
    let k = mut_ref_to_x;
}
"#),
        @r###"
    8..9 'x': &i32
    17..368 '{     ...o_x; }': ()
    27..28 'y': &i32
    31..32 'x': &i32
    42..44 '&z': &i32
    43..44 'z': i32
    47..48 'x': &i32
    58..59 'a': i32
    62..63 'z': i32
    73..79 '(c, d)': (i32, &str)
    74..75 'c': i32
    77..78 'd': &str
    82..94 '(1, "hello")': (i32, &str)
    83..84 '1': i32
    86..93 '"hello"': &str
    101..151 'for (e...     }': ()
    105..111 '(e, f)': ({unknown}, {unknown})
    106..107 'e': {unknown}
    109..110 'f': {unknown}
    115..124 'some_iter': {unknown}
    125..151 '{     ...     }': ()
    139..140 'g': {unknown}
    143..144 'e': {unknown}
    157..204 'if let...     }': ()
    164..169 '[val]': [{unknown}]
    165..168 'val': {unknown}
    172..175 'opt': [{unknown}]
    176..204 '{     ...     }': ()
    190..191 'h': {unknown}
    194..197 'val': {unknown}
    214..220 'lambda': |u64, u64, i32| -> i32
    223..255 '|a: u6...b; c }': |u64, u64, i32| -> i32
    224..225 'a': u64
    232..233 'b': u64
    235..236 'c': i32
    243..255 '{ a + b; c }': i32
    245..246 'a': u64
    245..250 'a + b': u64
    249..250 'b': u64
    252..253 'c': i32
    266..278 'ref ref_to_x': &&i32
    281..282 'x': &i32
    292..301 'mut mut_x': &i32
    304..305 'x': &i32
    315..335 'ref mu...f_to_x': &mut &i32
    338..339 'x': &i32
    349..350 'k': &mut &i32
    353..365 'mut_ref_to_x': &mut &i32
    "###
    );
}

#[test]
fn infer_literal_pattern() {
    assert_snapshot!(
        infer_with_mismatches(r#"
fn any<T>() -> T { loop {} }
fn test(x: &i32) {
    if let "foo" = any() {}
    if let 1 = any() {}
    if let 1u32 = any() {}
    if let 1f32 = any() {}
    if let 1.0 = any() {}
    if let true = any() {}
}
"#, true),
        @r###"
    17..28 '{ loop {} }': T
    19..26 'loop {}': !
    24..26 '{}': ()
    37..38 'x': &i32
    46..208 '{     ...) {} }': ()
    52..75 'if let...y() {}': ()
    59..64 '"foo"': &str
    59..64 '"foo"': &str
    67..70 'any': fn any<&str>() -> &str
    67..72 'any()': &str
    73..75 '{}': ()
    80..99 'if let...y() {}': ()
    87..88 '1': i32
    87..88 '1': i32
    91..94 'any': fn any<i32>() -> i32
    91..96 'any()': i32
    97..99 '{}': ()
    104..126 'if let...y() {}': ()
    111..115 '1u32': u32
    111..115 '1u32': u32
    118..121 'any': fn any<u32>() -> u32
    118..123 'any()': u32
    124..126 '{}': ()
    131..153 'if let...y() {}': ()
    138..142 '1f32': f32
    138..142 '1f32': f32
    145..148 'any': fn any<f32>() -> f32
    145..150 'any()': f32
    151..153 '{}': ()
    158..179 'if let...y() {}': ()
    165..168 '1.0': f64
    165..168 '1.0': f64
    171..174 'any': fn any<f64>() -> f64
    171..176 'any()': f64
    177..179 '{}': ()
    184..206 'if let...y() {}': ()
    191..195 'true': bool
    191..195 'true': bool
    198..201 'any': fn any<bool>() -> bool
    198..203 'any()': bool
    204..206 '{}': ()
    "###
    );
}

#[test]
fn infer_range_pattern() {
    assert_snapshot!(
        infer_with_mismatches(r#"
fn test(x: &i32) {
    if let 1..76 = 2u32 {}
    if let 1..=76 = 2u32 {}
}
"#, true),
        @r###"
    8..9 'x': &i32
    17..75 '{     ...2 {} }': ()
    23..45 'if let...u32 {}': ()
    30..35 '1..76': u32
    38..42 '2u32': u32
    43..45 '{}': ()
    50..73 'if let...u32 {}': ()
    57..63 '1..=76': u32
    66..70 '2u32': u32
    71..73 '{}': ()
    "###
    );
}

#[test]
fn infer_pattern_match_ergonomics() {
    assert_snapshot!(
        infer(r#"
struct A<T>(T);

fn test() {
    let A(n) = &A(1);
    let A(n) = &mut A(1);
}
"#),
    @r###"
    27..78 '{     ...(1); }': ()
    37..41 'A(n)': A<i32>
    39..40 'n': &i32
    44..49 '&A(1)': &A<i32>
    45..46 'A': A<i32>(i32) -> A<i32>
    45..49 'A(1)': A<i32>
    47..48 '1': i32
    59..63 'A(n)': A<i32>
    61..62 'n': &mut i32
    66..75 '&mut A(1)': &mut A<i32>
    71..72 'A': A<i32>(i32) -> A<i32>
    71..75 'A(1)': A<i32>
    73..74 '1': i32
    "###
    );
}

#[test]
fn infer_pattern_match_ergonomics_ref() {
    mark::check!(match_ergonomics_ref);
    assert_snapshot!(
        infer(r#"
fn test() {
    let v = &(1, &2);
    let (_, &w) = v;
}
"#),
    @r###"
    10..56 '{     ...= v; }': ()
    20..21 'v': &(i32, &i32)
    24..32 '&(1, &2)': &(i32, &i32)
    25..32 '(1, &2)': (i32, &i32)
    26..27 '1': i32
    29..31 '&2': &i32
    30..31 '2': i32
    42..49 '(_, &w)': (i32, &i32)
    43..44 '_': i32
    46..48 '&w': &i32
    47..48 'w': i32
    52..53 'v': &(i32, &i32)
    "###
    );
}

#[test]
fn infer_pattern_match_slice() {
    assert_snapshot!(
        infer(r#"
fn test() {
    let slice: &[f64] = &[0.0];
    match slice {
        &[] => {},
        &[a] => {
            a;
        },
        &[b, c] => {
            b;
            c;
        }
        _ => {}
    }
}
"#),
    @r###"
    10..209 '{     ...   } }': ()
    20..25 'slice': &[f64]
    36..42 '&[0.0]': &[f64; _]
    37..42 '[0.0]': [f64; _]
    38..41 '0.0': f64
    48..207 'match ...     }': ()
    54..59 'slice': &[f64]
    70..73 '&[]': &[f64]
    71..73 '[]': [f64]
    77..79 '{}': ()
    89..93 '&[a]': &[f64]
    90..93 '[a]': [f64]
    91..92 'a': f64
    97..123 '{     ...     }': ()
    111..112 'a': f64
    133..140 '&[b, c]': &[f64]
    134..140 '[b, c]': [f64]
    135..136 'b': f64
    138..139 'c': f64
    144..185 '{     ...     }': ()
    158..159 'b': f64
    173..174 'c': f64
    194..195 '_': &[f64]
    199..201 '{}': ()
    "###
    );
}

#[test]
fn infer_pattern_match_string_literal() {
    assert_snapshot!(
        infer_with_mismatches(r#"
fn test() {
    let s: &str = "hello";
    match s {
        "hello" => {}
        _ => {}
    }
}
"#, true),
    @r###"
    10..98 '{     ...   } }': ()
    20..21 's': &str
    30..37 '"hello"': &str
    43..96 'match ...     }': ()
    49..50 's': &str
    61..68 '"hello"': &str
    61..68 '"hello"': &str
    72..74 '{}': ()
    83..84 '_': &str
    88..90 '{}': ()
    "###
    );
}

#[test]
fn infer_pattern_match_or() {
    assert_snapshot!(
        infer_with_mismatches(r#"
fn test() {
    let s: &str = "hello";
    match s {
        "hello" | "world" => {}
        _ => {}
    }
}
"#, true),
    @r###"
    10..108 '{     ...   } }': ()
    20..21 's': &str
    30..37 '"hello"': &str
    43..106 'match ...     }': ()
    49..50 's': &str
    61..68 '"hello"': &str
    61..68 '"hello"': &str
    61..78 '"hello...world"': &str
    71..78 '"world"': &str
    71..78 '"world"': &str
    82..84 '{}': ()
    93..94 '_': &str
    98..100 '{}': ()
    "###
    );
}

#[test]
fn infer_pattern_match_arr() {
    assert_snapshot!(
        infer(r#"
fn test() {
    let arr: [f64; 2] = [0.0, 1.0];
    match arr {
        [1.0, a] => {
            a;
        },
        [b, c] => {
            b;
            c;
        }
    }
}
"#),
    @r###"
    10..179 '{     ...   } }': ()
    20..23 'arr': [f64; _]
    36..46 '[0.0, 1.0]': [f64; _]
    37..40 '0.0': f64
    42..45 '1.0': f64
    52..177 'match ...     }': ()
    58..61 'arr': [f64; _]
    72..80 '[1.0, a]': [f64; _]
    73..76 '1.0': f64
    73..76 '1.0': f64
    78..79 'a': f64
    84..110 '{     ...     }': ()
    98..99 'a': f64
    120..126 '[b, c]': [f64; _]
    121..122 'b': f64
    124..125 'c': f64
    130..171 '{     ...     }': ()
    144..145 'b': f64
    159..160 'c': f64
    "###
    );
}

#[test]
fn infer_adt_pattern() {
    assert_snapshot!(
        infer(r#"
enum E {
    A { x: usize },
    B
}

struct S(u32, E);

fn test() {
    let e = E::A { x: 3 };

    let S(y, z) = foo;
    let E::A { x: new_var } = e;

    match e {
        E::A { x } => x,
        E::B if foo => 1,
        E::B => 10,
    };

    let ref d @ E::A { .. } = e;
    d;
}
"#),
        @r###"
    67..288 '{     ...  d; }': ()
    77..78 'e': E
    81..94 'E::A { x: 3 }': E
    91..92 '3': usize
    105..112 'S(y, z)': S
    107..108 'y': u32
    110..111 'z': E
    115..118 'foo': S
    128..147 'E::A {..._var }': E
    138..145 'new_var': usize
    150..151 'e': E
    158..244 'match ...     }': usize
    164..165 'e': E
    176..186 'E::A { x }': E
    183..184 'x': usize
    190..191 'x': usize
    201..205 'E::B': E
    209..212 'foo': bool
    216..217 '1': usize
    227..231 'E::B': E
    235..237 '10': usize
    255..274 'ref d ...{ .. }': &E
    263..274 'E::A { .. }': E
    277..278 'e': E
    284..285 'd': &E
    "###
    );
}

#[test]
fn enum_variant_through_self_in_pattern() {
    assert_snapshot!(
        infer(r#"
enum E {
    A { x: usize },
    B(usize),
    C
}

impl E {
    fn test() {
        match (loop {}) {
            Self::A { x } => { x; },
            Self::B(x) => { x; },
            Self::C => {},
        };
    }
}
"#),
        @r###"
    75..217 '{     ...     }': ()
    85..210 'match ...     }': ()
    92..99 'loop {}': !
    97..99 '{}': ()
    115..128 'Self::A { x }': E
    125..126 'x': usize
    132..138 '{ x; }': ()
    134..135 'x': usize
    152..162 'Self::B(x)': E
    160..161 'x': usize
    166..172 '{ x; }': ()
    168..169 'x': usize
    186..193 'Self::C': E
    197..199 '{}': ()
    "###
    );
}

#[test]
fn infer_generics_in_patterns() {
    assert_snapshot!(
        infer(r#"
struct A<T> {
    x: T,
}

enum Option<T> {
    Some(T),
    None,
}

fn test(a1: A<u32>, o: Option<u64>) {
    let A { x: x2 } = a1;
    let A::<i64> { x: x3 } = A { x: 1 };
    match o {
        Option::Some(t) => t,
        _ => 1,
    };
}
"#),
        @r###"
    78..80 'a1': A<u32>
    90..91 'o': Option<u64>
    106..243 '{     ...  }; }': ()
    116..127 'A { x: x2 }': A<u32>
    123..125 'x2': u32
    130..132 'a1': A<u32>
    142..160 'A::<i6...: x3 }': A<i64>
    156..158 'x3': i64
    163..173 'A { x: 1 }': A<i64>
    170..171 '1': i64
    179..240 'match ...     }': u64
    185..186 'o': Option<u64>
    197..212 'Option::Some(t)': Option<u64>
    210..211 't': u64
    216..217 't': u64
    227..228 '_': Option<u64>
    232..233 '1': u64
    "###
    );
}

#[test]
fn infer_const_pattern() {
    assert_snapshot!(
        infer_with_mismatches(r#"
enum Option<T> { None }
use Option::None;
struct Foo;
const Bar: usize = 1;

fn test() {
    let a: Option<u32> = None;
    let b: Option<i64> = match a {
        None => None,
    };
    let _: () = match () { Foo => Foo }; // Expected mismatch
    let _: () = match () { Bar => Bar }; // Expected mismatch
}
"#, true),
        @r###"
    73..74 '1': usize
    87..309 '{     ...atch }': ()
    97..98 'a': Option<u32>
    114..118 'None': Option<u32>
    128..129 'b': Option<i64>
    145..182 'match ...     }': Option<i64>
    151..152 'a': Option<u32>
    163..167 'None': Option<u32>
    171..175 'None': Option<i64>
    192..193 '_': ()
    200..223 'match ... Foo }': Foo
    206..208 '()': ()
    211..214 'Foo': Foo
    218..221 'Foo': Foo
    254..255 '_': ()
    262..285 'match ... Bar }': usize
    268..270 '()': ()
    273..276 'Bar': usize
    280..283 'Bar': usize
    200..223: expected (), got Foo
    262..285: expected (), got usize
    "###
    );
}

#[test]
fn infer_guard() {
    assert_snapshot!(
        infer(r#"
struct S;
impl S { fn foo(&self) -> bool { false } }

fn main() {
    match S {
        s if s.foo() => (),
    }
}
    "#), @r###"
    27..31 'self': &S
    41..50 '{ false }': bool
    43..48 'false': bool
    64..115 '{     ...   } }': ()
    70..113 'match ...     }': ()
    76..77 'S': S
    88..89 's': S
    93..94 's': S
    93..100 's.foo()': bool
    104..106 '()': ()
    "###)
}

#[test]
fn match_ergonomics_in_closure_params() {
    assert_snapshot!(
        infer(r#"
#[lang = "fn_once"]
trait FnOnce<Args> {
    type Output;
}

fn foo<T, U, F: FnOnce(T) -> U>(t: T, f: F) -> U { loop {} }

fn test() {
    foo(&(1, "a"), |&(x, y)| x); // normal, no match ergonomics
    foo(&(1, "a"), |(x, y)| x);
}
"#),
        @r###"
    93..94 't': T
    99..100 'f': F
    110..121 '{ loop {} }': U
    112..119 'loop {}': !
    117..119 '{}': ()
    133..232 '{     ... x); }': ()
    139..142 'foo': fn foo<&(i32, &str), i32, |&(i32, &str)| -> i32>(&(i32, &str), |&(i32, &str)| -> i32) -> i32
    139..166 'foo(&(...y)| x)': i32
    143..152 '&(1, "a")': &(i32, &str)
    144..152 '(1, "a")': (i32, &str)
    145..146 '1': i32
    148..151 '"a"': &str
    154..165 '|&(x, y)| x': |&(i32, &str)| -> i32
    155..162 '&(x, y)': &(i32, &str)
    156..162 '(x, y)': (i32, &str)
    157..158 'x': i32
    160..161 'y': &str
    164..165 'x': i32
    203..206 'foo': fn foo<&(i32, &str), &i32, |&(i32, &str)| -> &i32>(&(i32, &str), |&(i32, &str)| -> &i32) -> &i32
    203..229 'foo(&(...y)| x)': &i32
    207..216 '&(1, "a")': &(i32, &str)
    208..216 '(1, "a")': (i32, &str)
    209..210 '1': i32
    212..215 '"a"': &str
    218..228 '|(x, y)| x': |&(i32, &str)| -> &i32
    219..225 '(x, y)': (i32, &str)
    220..221 'x': &i32
    223..224 'y': &&str
    227..228 'x': &i32
    "###
    );
}

#[test]
fn slice_tail_pattern() {
    assert_snapshot!(
        infer(r#"
fn foo(params: &[i32]) {
    match params {
        [head, tail @ ..] => {
        }
    }
}
"#),
        @r###"
    7..13 'params': &[i32]
    23..92 '{     ...   } }': ()
    29..90 'match ...     }': ()
    35..41 'params': &[i32]
    52..69 '[head,... @ ..]': [i32]
    53..57 'head': &i32
    59..68 'tail @ ..': &[i32]
    66..68 '..': [i32]
    73..84 '{         }': ()
    "###
    );
}