rust/src/test/ui/pattern/usefulness/issue-78123-non-exhaustive-reference.stderr

error[E0004]: non-exhaustive patterns: type `&A` is non-empty
  --> $DIR/issue-78123-non-exhaustive-reference.rs:6:11
   |
LL |     match a {}
   |           ^
   |
note: `A` defined here
  --> $DIR/issue-78123-non-exhaustive-reference.rs:1:6
   |
LL | enum A {}
   |      ^
   = note: the matched value is of type `&A`
   = note: references are always considered inhabited
help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
   |
LL ~     match a {
LL +         _ => todo!(),
LL +     }
   |

error: aborting due to previous error

For more information about this error, try `rustc --explain E0004`.
Add note to non-exhaustive match on reference to empty Rust prints "type `&A` is non-empty" even is A is empty. This is the intended behavior, but can be confusing. This commit adds a note to non-exhaustive pattern errors if they are a reference to something uninhabited. I did not add tests to check that the note is not shown for non-references or inhabited references, because this is already done in other tests. Maybe the added test is superfluous, because `always-inhabited-union-ref` already checks for this case. This does not handle &&Void or &&&void etc. I could add those as special cases as well and ignore people who need quadruple references. Fixes #78123 2021-01-03 07:13:33 -06:00			error[E0004]: non-exhaustive patterns: type `&A` is non-empty
Point at uncovered variants in enum definition in `note` instead of a `span_label` This makes the order of the output always consistent: 1. Place of the `match` missing arms 2. The `enum` definition span 3. The structured suggestion to add a fallthrough arm 2021-12-15 23:06:44 -06:00			`--> $DIR/issue-78123-non-exhaustive-reference.rs:6:11`
Add note to non-exhaustive match on reference to empty Rust prints "type `&A` is non-empty" even is A is empty. This is the intended behavior, but can be confusing. This commit adds a note to non-exhaustive pattern errors if they are a reference to something uninhabited. I did not add tests to check that the note is not shown for non-references or inhabited references, because this is already done in other tests. Maybe the added test is superfluous, because `always-inhabited-union-ref` already checks for this case. This does not handle &&Void or &&&void etc. I could add those as special cases as well and ignore people who need quadruple references. Fixes #78123 2021-01-03 07:13:33 -06:00			`\|`
			`LL \| match a {}`
			`\| ^`
			`\|`
Point at uncovered variants in enum definition in `note` instead of a `span_label` This makes the order of the output always consistent: 1. Place of the `match` missing arms 2. The `enum` definition span 3. The structured suggestion to add a fallthrough arm 2021-12-15 23:06:44 -06:00			note: `A` defined here
			`--> $DIR/issue-78123-non-exhaustive-reference.rs:1:6`
			`\|`
			`LL \| enum A {}`
			`\| ^`
Add note to non-exhaustive match on reference to empty Rust prints "type `&A` is non-empty" even is A is empty. This is the intended behavior, but can be confusing. This commit adds a note to non-exhaustive pattern errors if they are a reference to something uninhabited. I did not add tests to check that the note is not shown for non-references or inhabited references, because this is already done in other tests. Maybe the added test is superfluous, because `always-inhabited-union-ref` already checks for this case. This does not handle &&Void or &&&void etc. I could add those as special cases as well and ignore people who need quadruple references. Fixes #78123 2021-01-03 07:13:33 -06:00			= note: the matched value is of type `&A`
			`= note: references are always considered inhabited`
When encountering a match expr with no arms, suggest it Given ```rust match Some(42) {} ``` suggest ```rust match Some(42) { None \| Some(_) => todo!(), } ``` 2021-12-15 20:05:58 -06:00			`help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms`
			`\|`
			`LL ~ match a {`
			`LL + _ => todo!(),`
			`LL + }`
			`\|`
Add note to non-exhaustive match on reference to empty Rust prints "type `&A` is non-empty" even is A is empty. This is the intended behavior, but can be confusing. This commit adds a note to non-exhaustive pattern errors if they are a reference to something uninhabited. I did not add tests to check that the note is not shown for non-references or inhabited references, because this is already done in other tests. Maybe the added test is superfluous, because `always-inhabited-union-ref` already checks for this case. This does not handle &&Void or &&&void etc. I could add those as special cases as well and ignore people who need quadruple references. Fixes #78123 2021-01-03 07:13:33 -06:00
			`error: aborting due to previous error`

			For more information about this error, try `rustc --explain E0004`.