Improve placeholder in map_unit_fn

This commit is contained in:
Jacek Pospychala 2020-03-08 23:43:40 +01:00
parent d8f64b6eba
commit 697e3c89a7
4 changed files with 43 additions and 23 deletions

View File

@ -186,12 +186,12 @@ fn unit_closure<'a, 'tcx>(
/// `x.field` => `x_field`
/// `y` => `_y`
///
/// Anything else will return `_`.
/// Anything else will return `a`.
fn let_binding_name(cx: &LateContext<'_, '_>, var_arg: &hir::Expr<'_>) -> String {
match &var_arg.kind {
hir::ExprKind::Field(_, _) => snippet(cx, var_arg.span, "_").replace(".", "_"),
hir::ExprKind::Path(_) => format!("_{}", snippet(cx, var_arg.span, "")),
_ => "_".to_string(),
_ => "a".to_string(),
}
}

View File

@ -13,6 +13,10 @@ fn plus_one(value: usize) -> usize {
value + 1
}
fn option() -> Option<usize> {
Some(10)
}
struct HasOption {
field: Option<usize>,
}
@ -73,6 +77,8 @@ fn option_map_unit_fn() {
if let Some(value) = x.field { plus_one(value + captured); }
if let Some(ref value) = x.field { do_nothing(value + captured) }}
if let Some(ref value) = x.field { do_nothing(value + captured) }
if let Some(a) = option() { do_nothing(a) }}
fn main() {}

View File

@ -13,6 +13,10 @@ fn plus_one(value: usize) -> usize {
value + 1
}
fn option() -> Option<usize> {
Some(10)
}
struct HasOption {
field: Option<usize>,
}
@ -73,6 +77,8 @@ fn option_map_unit_fn() {
x.field.map(|value| { { plus_one(value + captured); } });
x.field.map(|ref value| { do_nothing(value + captured) });}
x.field.map(|ref value| { do_nothing(value + captured) });
option().map(do_nothing);}
fn main() {}

View File

@ -1,5 +1,5 @@
error: called `map(f)` on an `Option` value where `f` is a function that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:34:5
--> $DIR/option_map_unit_fn_fixable.rs:38:5
|
LL | x.field.map(do_nothing);
| ^^^^^^^^^^^^^^^^^^^^^^^-
@ -9,7 +9,7 @@ LL | x.field.map(do_nothing);
= note: `-D clippy::option-map-unit-fn` implied by `-D warnings`
error: called `map(f)` on an `Option` value where `f` is a function that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:36:5
--> $DIR/option_map_unit_fn_fixable.rs:40:5
|
LL | x.field.map(do_nothing);
| ^^^^^^^^^^^^^^^^^^^^^^^-
@ -17,7 +17,7 @@ LL | x.field.map(do_nothing);
| help: try this: `if let Some(x_field) = x.field { do_nothing(x_field) }`
error: called `map(f)` on an `Option` value where `f` is a function that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:38:5
--> $DIR/option_map_unit_fn_fixable.rs:42:5
|
LL | x.field.map(diverge);
| ^^^^^^^^^^^^^^^^^^^^-
@ -25,7 +25,7 @@ LL | x.field.map(diverge);
| help: try this: `if let Some(x_field) = x.field { diverge(x_field) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:44:5
--> $DIR/option_map_unit_fn_fixable.rs:48:5
|
LL | x.field.map(|value| x.do_option_nothing(value + captured));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -33,7 +33,7 @@ LL | x.field.map(|value| x.do_option_nothing(value + captured));
| help: try this: `if let Some(value) = x.field { x.do_option_nothing(value + captured) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:46:5
--> $DIR/option_map_unit_fn_fixable.rs:50:5
|
LL | x.field.map(|value| { x.do_option_plus_one(value + captured); });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -41,7 +41,7 @@ LL | x.field.map(|value| { x.do_option_plus_one(value + captured); });
| help: try this: `if let Some(value) = x.field { x.do_option_plus_one(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:49:5
--> $DIR/option_map_unit_fn_fixable.rs:53:5
|
LL | x.field.map(|value| do_nothing(value + captured));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -49,7 +49,7 @@ LL | x.field.map(|value| do_nothing(value + captured));
| help: try this: `if let Some(value) = x.field { do_nothing(value + captured) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:51:5
--> $DIR/option_map_unit_fn_fixable.rs:55:5
|
LL | x.field.map(|value| { do_nothing(value + captured) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -57,7 +57,7 @@ LL | x.field.map(|value| { do_nothing(value + captured) });
| help: try this: `if let Some(value) = x.field { do_nothing(value + captured) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:53:5
--> $DIR/option_map_unit_fn_fixable.rs:57:5
|
LL | x.field.map(|value| { do_nothing(value + captured); });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -65,7 +65,7 @@ LL | x.field.map(|value| { do_nothing(value + captured); });
| help: try this: `if let Some(value) = x.field { do_nothing(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:55:5
--> $DIR/option_map_unit_fn_fixable.rs:59:5
|
LL | x.field.map(|value| { { do_nothing(value + captured); } });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -73,7 +73,7 @@ LL | x.field.map(|value| { { do_nothing(value + captured); } });
| help: try this: `if let Some(value) = x.field { do_nothing(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:58:5
--> $DIR/option_map_unit_fn_fixable.rs:62:5
|
LL | x.field.map(|value| diverge(value + captured));
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -81,7 +81,7 @@ LL | x.field.map(|value| diverge(value + captured));
| help: try this: `if let Some(value) = x.field { diverge(value + captured) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:60:5
--> $DIR/option_map_unit_fn_fixable.rs:64:5
|
LL | x.field.map(|value| { diverge(value + captured) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -89,7 +89,7 @@ LL | x.field.map(|value| { diverge(value + captured) });
| help: try this: `if let Some(value) = x.field { diverge(value + captured) }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:62:5
--> $DIR/option_map_unit_fn_fixable.rs:66:5
|
LL | x.field.map(|value| { diverge(value + captured); });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -97,7 +97,7 @@ LL | x.field.map(|value| { diverge(value + captured); });
| help: try this: `if let Some(value) = x.field { diverge(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:64:5
--> $DIR/option_map_unit_fn_fixable.rs:68:5
|
LL | x.field.map(|value| { { diverge(value + captured); } });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -105,7 +105,7 @@ LL | x.field.map(|value| { { diverge(value + captured); } });
| help: try this: `if let Some(value) = x.field { diverge(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:69:5
--> $DIR/option_map_unit_fn_fixable.rs:73:5
|
LL | x.field.map(|value| { let y = plus_one(value + captured); });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -113,7 +113,7 @@ LL | x.field.map(|value| { let y = plus_one(value + captured); });
| help: try this: `if let Some(value) = x.field { let y = plus_one(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:71:5
--> $DIR/option_map_unit_fn_fixable.rs:75:5
|
LL | x.field.map(|value| { plus_one(value + captured); });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -121,7 +121,7 @@ LL | x.field.map(|value| { plus_one(value + captured); });
| help: try this: `if let Some(value) = x.field { plus_one(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:73:5
--> $DIR/option_map_unit_fn_fixable.rs:77:5
|
LL | x.field.map(|value| { { plus_one(value + captured); } });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
@ -129,12 +129,20 @@ LL | x.field.map(|value| { { plus_one(value + captured); } });
| help: try this: `if let Some(value) = x.field { plus_one(value + captured); }`
error: called `map(f)` on an `Option` value where `f` is a closure that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:76:5
--> $DIR/option_map_unit_fn_fixable.rs:80:5
|
LL | x.field.map(|ref value| { do_nothing(value + captured) });}
LL | x.field.map(|ref value| { do_nothing(value + captured) });
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-
| |
| help: try this: `if let Some(ref value) = x.field { do_nothing(value + captured) }`
error: aborting due to 17 previous errors
error: called `map(f)` on an `Option` value where `f` is a function that returns the unit type
--> $DIR/option_map_unit_fn_fixable.rs:82:5
|
LL | option().map(do_nothing);}
| ^^^^^^^^^^^^^^^^^^^^^^^^-
| |
| help: try this: `if let Some(a) = option() { do_nothing(a) }`
error: aborting due to 18 previous errors