Add a bunch more tests.

Author: davidtwco

src/test/ui/rfc-2008-non-exhaustive/uninhabited/auxiliary/uninhabited.rs

@@ -23,3 +23,11 @@ pub enum PartiallyInhabitedVariants {
     Tuple(u8),
     #[non_exhaustive] Struct { x: ! }
 }
+
+pub struct IndirectUninhabitedEnum(UninhabitedEnum);
+
+pub struct IndirectUninhabitedStruct(UninhabitedStruct);
+
+pub struct IndirectUninhabitedTupleStruct(UninhabitedTupleStruct);
+
+pub struct IndirectUninhabitedVariants(UninhabitedVariants);

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match.rs

@@ -0,0 +1,36 @@
+// aux-build:uninhabited.rs
+#![feature(never_type)]
+
+extern crate uninhabited;
+
+use uninhabited::{
+    IndirectUninhabitedEnum,
+    IndirectUninhabitedStruct,
+    IndirectUninhabitedTupleStruct,
+    IndirectUninhabitedVariants,
+};
+
+struct A;
+
+// This test checks that an empty match on a non-exhaustive uninhabited type through a level of
+// indirection from an extern crate will not compile.
+
+fn cannot_empty_match_on_empty_enum_to_anything(x: IndirectUninhabitedEnum) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_struct_to_anything(x: IndirectUninhabitedStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_tuple_struct_to_anything(x: IndirectUninhabitedTupleStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_enum_with_empty_variants_struct_to_anything(
+    x: IndirectUninhabitedVariants,
+) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn main() {}

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match.stderr

@@ -0,0 +1,35 @@
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedEnum` of type `uninhabited::IndirectUninhabitedEnum` is not handled
+  --> $DIR/indirect_match.rs:19:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedStruct` of type `uninhabited::IndirectUninhabitedStruct` is not handled
+  --> $DIR/indirect_match.rs:23:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedTupleStruct` of type `uninhabited::IndirectUninhabitedTupleStruct` is not handled
+  --> $DIR/indirect_match.rs:27:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedVariants` of type `uninhabited::IndirectUninhabitedVariants` is not handled
+  --> $DIR/indirect_match.rs:33:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0004`.

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match_same_crate.rs

@@ -0,0 +1,52 @@
+#![feature(never_type)]
+#![feature(non_exhaustive)]
+
+#[non_exhaustive]
+pub enum UninhabitedEnum {
+}
+
+#[non_exhaustive]
+pub struct UninhabitedStruct {
+    _priv: !,
+}
+
+#[non_exhaustive]
+pub struct UninhabitedTupleStruct(!);
+
+pub enum UninhabitedVariants {
+    #[non_exhaustive] Tuple(!),
+    #[non_exhaustive] Struct { x: ! }
+}
+
+pub struct IndirectUninhabitedEnum(UninhabitedEnum);
+
+pub struct IndirectUninhabitedStruct(UninhabitedStruct);
+
+pub struct IndirectUninhabitedTupleStruct(UninhabitedTupleStruct);
+
+pub struct IndirectUninhabitedVariants(UninhabitedVariants);
+
+struct A;
+
+// This test checks that an empty match on a non-exhaustive uninhabited type through a level of
+// indirection from the defining crate will not compile without `#![feature(exhaustive_patterns)]`.
+
+fn cannot_empty_match_on_empty_enum_to_anything(x: IndirectUninhabitedEnum) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_struct_to_anything(x: IndirectUninhabitedStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_tuple_struct_to_anything(x: IndirectUninhabitedTupleStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_enum_with_empty_variants_struct_to_anything(
+    x: IndirectUninhabitedVariants,
+) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn main() {}

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match_same_crate.stderr

@@ -0,0 +1,59 @@
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedEnum` of type `IndirectUninhabitedEnum` is not handled
+  --> $DIR/indirect_match_same_crate.rs:35:11
+   |
+LL | pub struct IndirectUninhabitedEnum(UninhabitedEnum);
+   | ----------------------------------------------------
+   | |          |
+   | |          variant not covered
+   | `IndirectUninhabitedEnum` defined here
+...
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedStruct` of type `IndirectUninhabitedStruct` is not handled
+  --> $DIR/indirect_match_same_crate.rs:39:11
+   |
+LL | pub struct IndirectUninhabitedStruct(UninhabitedStruct);
+   | --------------------------------------------------------
+   | |          |
+   | |          variant not covered
+   | `IndirectUninhabitedStruct` defined here
+...
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedTupleStruct` of type `IndirectUninhabitedTupleStruct` is not handled
+  --> $DIR/indirect_match_same_crate.rs:43:11
+   |
+LL | pub struct IndirectUninhabitedTupleStruct(UninhabitedTupleStruct);
+   | ------------------------------------------------------------------
+   | |          |
+   | |          variant not covered
+   | `IndirectUninhabitedTupleStruct` defined here
+...
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `IndirectUninhabitedVariants` of type `IndirectUninhabitedVariants` is not handled
+  --> $DIR/indirect_match_same_crate.rs:49:11
+   |
+LL | pub struct IndirectUninhabitedVariants(UninhabitedVariants);
+   | ------------------------------------------------------------
+   | |          |
+   | |          variant not covered
+   | `IndirectUninhabitedVariants` defined here
+...
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0004`.

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match_with_exhaustive_patterns.rs

@@ -0,0 +1,40 @@
+// aux-build:uninhabited.rs
+#![deny(unreachable_patterns)]
+#![feature(exhaustive_patterns)]
+#![feature(never_type)]
+
+extern crate uninhabited;
+
+use uninhabited::{
+    IndirectUninhabitedEnum,
+    IndirectUninhabitedStruct,
+    IndirectUninhabitedTupleStruct,
+    IndirectUninhabitedVariants,
+};
+
+struct A;
+
+// This test checks that an empty match on a non-exhaustive uninhabited type through a level of
+// indirection from an extern crate will not compile. In particular, this enables the
+// `exhaustive_patterns` feature as this can change the branch used in the compiler to determine
+// this.
+
+fn cannot_empty_match_on_empty_enum_to_anything(x: IndirectUninhabitedEnum) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_struct_to_anything(x: IndirectUninhabitedStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_tuple_struct_to_anything(x: IndirectUninhabitedTupleStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_enum_with_empty_variants_struct_to_anything(
+    x: IndirectUninhabitedVariants,
+) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn main() {}

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match_with_exhaustive_patterns.stderr

@@ -0,0 +1,35 @@
+error[E0004]: non-exhaustive patterns: type `uninhabited::IndirectUninhabitedEnum` is non-empty
+  --> $DIR/indirect_match_with_exhaustive_patterns.rs:23:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: type `uninhabited::IndirectUninhabitedStruct` is non-empty
+  --> $DIR/indirect_match_with_exhaustive_patterns.rs:27:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: type `uninhabited::IndirectUninhabitedTupleStruct` is non-empty
+  --> $DIR/indirect_match_with_exhaustive_patterns.rs:31:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: type `uninhabited::IndirectUninhabitedVariants` is non-empty
+  --> $DIR/indirect_match_with_exhaustive_patterns.rs:37:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0004`.

src/test/ui/rfc-2008-non-exhaustive/uninhabited/indirect_match_with_exhaustive_patterns_same_crate.rs

@@ -0,0 +1,58 @@
+// compile-pass
+// skip-codegen
+#![deny(unreachable_patterns)]
+#![feature(exhaustive_patterns)]
+#![feature(never_type)]
+#![feature(non_exhaustive)]
+
+#[non_exhaustive]
+pub enum UninhabitedEnum {
+}
+
+#[non_exhaustive]
+pub struct UninhabitedStruct {
+    _priv: !,
+}
+
+#[non_exhaustive]
+pub struct UninhabitedTupleStruct(!);
+
+pub enum UninhabitedVariants {
+    #[non_exhaustive] Tuple(!),
+    #[non_exhaustive] Struct { x: ! }
+}
+
+pub struct IndirectUninhabitedEnum(UninhabitedEnum);
+
+pub struct IndirectUninhabitedStruct(UninhabitedStruct);
+
+pub struct IndirectUninhabitedTupleStruct(UninhabitedTupleStruct);
+
+pub struct IndirectUninhabitedVariants(UninhabitedVariants);
+
+struct A;
+
+// This test checks that an empty match on a non-exhaustive uninhabited type from the defining crate
+// will compile. In particular, this enables the `exhaustive_patterns` feature as this can
+// change the branch used in the compiler to determine this.
+// Codegen is skipped because tests with long names can cause issues on Windows CI, see #60648.
+
+fn cannot_empty_match_on_empty_enum_to_anything(x: IndirectUninhabitedEnum) -> A {
+    match x {}
+}
+
+fn cannot_empty_match_on_empty_struct_to_anything(x: IndirectUninhabitedStruct) -> A {
+    match x {}
+}
+
+fn cannot_empty_match_on_empty_tuple_struct_to_anything(x: IndirectUninhabitedTupleStruct) -> A {
+    match x {}
+}
+
+fn cannot_empty_match_on_enum_with_empty_variants_struct_to_anything(
+    x: IndirectUninhabitedVariants,
+) -> A {
+    match x {}
+}
+
+fn main() {}

src/test/ui/rfc-2008-non-exhaustive/uninhabited/match.rs

@@ -5,6 +5,9 @@ extern crate uninhabited;
 
 use uninhabited::{
     UninhabitedEnum,
+    UninhabitedStruct,
+    UninhabitedTupleStruct,
+    UninhabitedVariants,
 };
 
 struct A;
@@ -16,4 +19,16 @@ fn cannot_empty_match_on_empty_enum_to_anything(x: UninhabitedEnum) -> A {
     match x {} //~ ERROR non-exhaustive patterns
 }
 
+fn cannot_empty_match_on_empty_struct_to_anything(x: UninhabitedStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_empty_tuple_struct_to_anything(x: UninhabitedTupleStruct) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
+fn cannot_empty_match_on_enum_with_empty_variants_struct_to_anything(x: UninhabitedVariants) -> A {
+    match x {} //~ ERROR non-exhaustive patterns
+}
+
 fn main() {}

src/test/ui/rfc-2008-non-exhaustive/uninhabited/match.stderr

@@ -1,11 +1,35 @@
 error[E0004]: non-exhaustive patterns: type `uninhabited::UninhabitedEnum` is non-empty
-  --> $DIR/match.rs:16:11
+  --> $DIR/match.rs:19:11
    |
 LL |     match x {}
    |           ^
    |
    = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
 
-error: aborting due to previous error
+error[E0004]: non-exhaustive patterns: pattern `UninhabitedStruct` of type `uninhabited::UninhabitedStruct` is not handled
+  --> $DIR/match.rs:23:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: pattern `UninhabitedTupleStruct` of type `uninhabited::UninhabitedTupleStruct` is not handled
+  --> $DIR/match.rs:27:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error[E0004]: non-exhaustive patterns: multiple patterns of type `uninhabited::UninhabitedVariants` are not handled
+  --> $DIR/match.rs:31:11
+   |
+LL |     match x {}
+   |           ^
+   |
+   = help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
+
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0004`.