From 5dd09b079046dafc0a07308bab74efa47d1f13b2 Mon Sep 17 00:00:00 2001
From: Mara Bos <m-ou.se@m-ou.se>
Date: Wed, 7 Jul 2021 16:25:46 +0000
Subject: [PATCH 1/8] Move [debug_]assert_matches to mod {core, std}::assert.

---
 compiler/rustc_middle/src/ich/impls_syntax.rs  |  1 +
 compiler/rustc_mir/src/interpret/memory.rs     |  1 +
 library/core/src/lib.rs                        | 10 ++++++++++
 library/core/src/macros/mod.rs                 | 17 +++++++++++------
 library/std/src/lib.rs                         |  4 ++--
 src/test/ui/macros/assert-matches-macro-msg.rs |  2 ++
 src/test/ui/matches2021.rs                     |  2 ++
 src/test/ui/resolve/resolve-hint-macro.rs      |  4 ++--
 src/test/ui/resolve/resolve-hint-macro.stderr  | 10 +++++-----
 9 files changed, 36 insertions(+), 15 deletions(-)

diff --git a/compiler/rustc_middle/src/ich/impls_syntax.rs b/compiler/rustc_middle/src/ich/impls_syntax.rs
index 2d8f661ef59e9..1c66f831b5f4b 100644
--- a/compiler/rustc_middle/src/ich/impls_syntax.rs
+++ b/compiler/rustc_middle/src/ich/impls_syntax.rs
@@ -6,6 +6,7 @@ use crate::ich::StableHashingContext;
 use rustc_ast as ast;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_span::{BytePos, NormalizedPos, SourceFile};
+use std::assert::assert_matches;
 
 use smallvec::SmallVec;
 
diff --git a/compiler/rustc_mir/src/interpret/memory.rs b/compiler/rustc_mir/src/interpret/memory.rs
index 77de19ac674c2..577a036815a98 100644
--- a/compiler/rustc_mir/src/interpret/memory.rs
+++ b/compiler/rustc_mir/src/interpret/memory.rs
@@ -6,6 +6,7 @@
 //! integer. It is crucial that these operations call `check_align` *before*
 //! short-circuiting the empty case!
 
+use std::assert::assert_matches;
 use std::borrow::Cow;
 use std::collections::VecDeque;
 use std::convert::{TryFrom, TryInto};
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 949ef27f018e4..65235a0db0359 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -182,6 +182,16 @@ use prelude::v1::*;
 #[macro_use]
 mod macros;
 
+// We don't export this through #[macro_export] for now, to avoid breakage.
+// See https://github.com/rust-lang/rust/issues/82913
+#[cfg(not(test))]
+#[unstable(feature = "assert_matches", issue = "82775")]
+/// Unstable module containing the unstable `assert_matches` macro.
+pub mod assert {
+    #[unstable(feature = "assert_matches", issue = "82775")]
+    pub use crate::macros::{assert_matches, debug_assert_matches};
+}
+
 #[macro_use]
 mod internal_macros;
 
diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index 7eb65483b99e7..5a8e2f543921b 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -126,6 +126,8 @@ macro_rules! assert_ne {
 /// ```
 /// #![feature(assert_matches)]
 ///
+/// use std::assert::assert_matches;
+///
 /// let a = 1u32.checked_add(2);
 /// let b = 1u32.checked_sub(2);
 /// assert_matches!(a, Some(_));
@@ -134,10 +136,10 @@ macro_rules! assert_ne {
 /// let c = Ok("abc".to_string());
 /// assert_matches!(c, Ok(x) | Err(x) if x.len() < 100);
 /// ```
-#[macro_export]
 #[unstable(feature = "assert_matches", issue = "82775")]
 #[allow_internal_unstable(core_panic)]
-macro_rules! assert_matches {
+#[rustc_macro_transparency = "semitransparent"]
+pub macro assert_matches {
     ($left:expr, $( $pattern:pat_param )|+ $( if $guard: expr )? $(,)?) => ({
         match $left {
             $( $pattern )|+ $( if $guard )? => {}
@@ -149,7 +151,7 @@ macro_rules! assert_matches {
                 );
             }
         }
-    });
+    }),
     ($left:expr, $( $pattern:pat_param )|+ $( if $guard: expr )?, $($arg:tt)+) => ({
         match $left {
             $( $pattern )|+ $( if $guard )? => {}
@@ -161,7 +163,7 @@ macro_rules! assert_matches {
                 );
             }
         }
-    });
+    }),
 }
 
 /// Asserts that a boolean expression is `true` at runtime.
@@ -283,6 +285,8 @@ macro_rules! debug_assert_ne {
 /// ```
 /// #![feature(assert_matches)]
 ///
+/// use std::assert::debug_assert_matches;
+///
 /// let a = 1u32.checked_add(2);
 /// let b = 1u32.checked_sub(2);
 /// debug_assert_matches!(a, Some(_));
@@ -294,8 +298,9 @@ macro_rules! debug_assert_ne {
 #[macro_export]
 #[unstable(feature = "assert_matches", issue = "82775")]
 #[allow_internal_unstable(assert_matches)]
-macro_rules! debug_assert_matches {
-    ($($arg:tt)*) => (if $crate::cfg!(debug_assertions) { $crate::assert_matches!($($arg)*); })
+#[rustc_macro_transparency = "semitransparent"]
+pub macro debug_assert_matches($($arg:tt)*) {
+    if $crate::cfg!(debug_assertions) { $crate::assert::assert_matches!($($arg)*); }
 }
 
 /// Returns whether the given expression matches any of the given patterns.
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index c4f21587457c1..e83a000e38b2d 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -552,8 +552,8 @@ pub use std_detect::{
 #[stable(feature = "rust1", since = "1.0.0")]
 #[allow(deprecated, deprecated_in_future)]
 pub use core::{
-    assert_eq, assert_matches, assert_ne, debug_assert, debug_assert_eq, debug_assert_matches,
-    debug_assert_ne, matches, r#try, todo, unimplemented, unreachable, write, writeln,
+    assert_eq, assert_ne, debug_assert, debug_assert_eq, debug_assert_ne, matches, r#try, todo,
+    unimplemented, unreachable, write, writeln,
 };
 
 // Re-export built-in macros defined through libcore.
diff --git a/src/test/ui/macros/assert-matches-macro-msg.rs b/src/test/ui/macros/assert-matches-macro-msg.rs
index 43be9532f5d1c..714a6561a6d09 100644
--- a/src/test/ui/macros/assert-matches-macro-msg.rs
+++ b/src/test/ui/macros/assert-matches-macro-msg.rs
@@ -6,6 +6,8 @@
 
 #![feature(assert_matches)]
 
+use std::assert::assert_matches;
+
 fn main() {
     assert_matches!(1 + 1, 3, "1 + 1 definitely should be 3");
 }
diff --git a/src/test/ui/matches2021.rs b/src/test/ui/matches2021.rs
index 1090b1578ba51..a6fa5128d2f86 100644
--- a/src/test/ui/matches2021.rs
+++ b/src/test/ui/matches2021.rs
@@ -6,6 +6,8 @@
 
 #![feature(assert_matches)]
 
+use std::assert::assert_matches;
+
 fn main() {
     assert!(matches!((), ()));
     assert_matches!((), ());
diff --git a/src/test/ui/resolve/resolve-hint-macro.rs b/src/test/ui/resolve/resolve-hint-macro.rs
index 6155ae7bcdfdf..5532c8b90e326 100644
--- a/src/test/ui/resolve/resolve-hint-macro.rs
+++ b/src/test/ui/resolve/resolve-hint-macro.rs
@@ -1,4 +1,4 @@
 fn main() {
-    assert(true);
-    //~^ ERROR expected function, found macro `assert`
+    assert_eq(1, 1);
+    //~^ ERROR expected function, found macro `assert_eq`
 }
diff --git a/src/test/ui/resolve/resolve-hint-macro.stderr b/src/test/ui/resolve/resolve-hint-macro.stderr
index 7d35ce7e65e58..efcfc7198ab51 100644
--- a/src/test/ui/resolve/resolve-hint-macro.stderr
+++ b/src/test/ui/resolve/resolve-hint-macro.stderr
@@ -1,13 +1,13 @@
-error[E0423]: expected function, found macro `assert`
+error[E0423]: expected function, found macro `assert_eq`
   --> $DIR/resolve-hint-macro.rs:2:5
    |
-LL |     assert(true);
-   |     ^^^^^^ not a function
+LL |     assert_eq(1, 1);
+   |     ^^^^^^^^^ not a function
    |
 help: use `!` to invoke the macro
    |
-LL |     assert!(true);
-   |           ^
+LL |     assert_eq!(1, 1);
+   |              ^
 
 error: aborting due to previous error
 

From 1b60ea8890d016c905a740037e2a49688bc3507a Mon Sep 17 00:00:00 2001
From: Jane Lusby <jlusby@yaah.dev>
Date: Fri, 16 Jul 2021 09:18:14 -0700
Subject: [PATCH 2/8] rename assert_matches module

---
 compiler/rustc_middle/src/ich/impls_syntax.rs | 2 +-
 compiler/rustc_mir/src/interpret/memory.rs    | 2 +-
 library/core/src/lib.rs                       | 2 +-
 library/std/src/lib.rs                        | 6 +++---
 4 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/compiler/rustc_middle/src/ich/impls_syntax.rs b/compiler/rustc_middle/src/ich/impls_syntax.rs
index 1c66f831b5f4b..acf2990b64348 100644
--- a/compiler/rustc_middle/src/ich/impls_syntax.rs
+++ b/compiler/rustc_middle/src/ich/impls_syntax.rs
@@ -6,7 +6,7 @@ use crate::ich::StableHashingContext;
 use rustc_ast as ast;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_span::{BytePos, NormalizedPos, SourceFile};
-use std::assert::assert_matches;
+use std::assert_matches::assert_matches;
 
 use smallvec::SmallVec;
 
diff --git a/compiler/rustc_mir/src/interpret/memory.rs b/compiler/rustc_mir/src/interpret/memory.rs
index 577a036815a98..76073599e22b1 100644
--- a/compiler/rustc_mir/src/interpret/memory.rs
+++ b/compiler/rustc_mir/src/interpret/memory.rs
@@ -6,7 +6,7 @@
 //! integer. It is crucial that these operations call `check_align` *before*
 //! short-circuiting the empty case!
 
-use std::assert::assert_matches;
+use std::assert_matches::assert_matches;
 use std::borrow::Cow;
 use std::collections::VecDeque;
 use std::convert::{TryFrom, TryInto};
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 65235a0db0359..0bb0f8768a0ef 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -187,7 +187,7 @@ mod macros;
 #[cfg(not(test))]
 #[unstable(feature = "assert_matches", issue = "82775")]
 /// Unstable module containing the unstable `assert_matches` macro.
-pub mod assert {
+pub mod assert_matches {
     #[unstable(feature = "assert_matches", issue = "82775")]
     pub use crate::macros::{assert_matches, debug_assert_matches};
 }
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index e83a000e38b2d..31dcd9546bc8a 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -560,9 +560,9 @@ pub use core::{
 #[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
 #[allow(deprecated)]
 pub use core::{
-    asm, assert, cfg, column, compile_error, concat, concat_idents, env, file, format_args,
-    format_args_nl, global_asm, include, include_bytes, include_str, line, llvm_asm, log_syntax,
-    module_path, option_env, stringify, trace_macros,
+    asm, assert, assert_matches, cfg, column, compile_error, concat, concat_idents, env, file,
+    format_args, format_args_nl, global_asm, include, include_bytes, include_str, line, llvm_asm,
+    log_syntax, module_path, option_env, stringify, trace_macros,
 };
 
 #[stable(feature = "core_primitive", since = "1.43.0")]

From 96941c7c121155538a6b8ebdafaedd3a5dc58433 Mon Sep 17 00:00:00 2001
From: Jane Lusby <jlusby@yaah.dev>
Date: Fri, 16 Jul 2021 11:26:20 -0700
Subject: [PATCH 3/8] fix ui tests

---
 src/test/ui/macros/assert-matches-macro-msg.rs | 2 +-
 src/test/ui/matches2021.rs                     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/test/ui/macros/assert-matches-macro-msg.rs b/src/test/ui/macros/assert-matches-macro-msg.rs
index 714a6561a6d09..fd8cd5a1a0566 100644
--- a/src/test/ui/macros/assert-matches-macro-msg.rs
+++ b/src/test/ui/macros/assert-matches-macro-msg.rs
@@ -6,7 +6,7 @@
 
 #![feature(assert_matches)]
 
-use std::assert::assert_matches;
+use std::assert_matches::assert_matches;
 
 fn main() {
     assert_matches!(1 + 1, 3, "1 + 1 definitely should be 3");
diff --git a/src/test/ui/matches2021.rs b/src/test/ui/matches2021.rs
index a6fa5128d2f86..f5497c1d16de6 100644
--- a/src/test/ui/matches2021.rs
+++ b/src/test/ui/matches2021.rs
@@ -6,7 +6,7 @@
 
 #![feature(assert_matches)]
 
-use std::assert::assert_matches;
+use std::assert_matches::assert_matches;
 
 fn main() {
     assert!(matches!((), ()));

From 5142fa3e3aeb84ab6590cf1b9db01641b19b7b83 Mon Sep 17 00:00:00 2001
From: Jane Lusby <jlusby@yaah.dev>
Date: Fri, 16 Jul 2021 12:16:39 -0700
Subject: [PATCH 4/8] pls this time

---
 library/core/src/macros/mod.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index 5a8e2f543921b..a763ae27cd14b 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -126,7 +126,7 @@ macro_rules! assert_ne {
 /// ```
 /// #![feature(assert_matches)]
 ///
-/// use std::assert::assert_matches;
+/// use std::assert_matches::assert_matches;
 ///
 /// let a = 1u32.checked_add(2);
 /// let b = 1u32.checked_sub(2);
@@ -300,7 +300,7 @@ macro_rules! debug_assert_ne {
 #[allow_internal_unstable(assert_matches)]
 #[rustc_macro_transparency = "semitransparent"]
 pub macro debug_assert_matches($($arg:tt)*) {
-    if $crate::cfg!(debug_assertions) { $crate::assert::assert_matches!($($arg)*); }
+    if $crate::cfg!(debug_assertions) { $crate::assert_matches::assert_matches!($($arg)*); }
 }
 
 /// Returns whether the given expression matches any of the given patterns.

From 8fde11b20831a9d82079e0e84745ca77713831ed Mon Sep 17 00:00:00 2001
From: Jane Lusby <jlusby@yaah.dev>
Date: Fri, 16 Jul 2021 13:25:11 -0700
Subject: [PATCH 5/8] i sweat to god

---
 library/core/src/macros/mod.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs
index a763ae27cd14b..1a3c088e922a0 100644
--- a/library/core/src/macros/mod.rs
+++ b/library/core/src/macros/mod.rs
@@ -285,7 +285,7 @@ macro_rules! debug_assert_ne {
 /// ```
 /// #![feature(assert_matches)]
 ///
-/// use std::assert::debug_assert_matches;
+/// use std::assert_matches::debug_assert_matches;
 ///
 /// let a = 1u32.checked_add(2);
 /// let b = 1u32.checked_sub(2);

From ef7502b878720d4f948b3a535f77e03b2fcc4060 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Fri, 9 Jul 2021 10:01:23 -0700
Subject: [PATCH 6/8] Fix rust-analyzer install when not available.

---
 src/bootstrap/install.rs | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/bootstrap/install.rs b/src/bootstrap/install.rs
index 13ee909afd5e4..6f3054538a898 100644
--- a/src/bootstrap/install.rs
+++ b/src/bootstrap/install.rs
@@ -165,10 +165,15 @@ install!((self, builder, _config),
         }
     };
     RustAnalyzer, "rust-analyzer", Self::should_build(_config), only_hosts: true, {
-        let tarball = builder
-            .ensure(dist::RustAnalyzer { compiler: self.compiler, target: self.target })
-            .expect("missing rust-analyzer");
-        install_sh(builder, "rust-analyzer", self.compiler.stage, Some(self.target), &tarball);
+        if let Some(tarball) =
+            builder.ensure(dist::RustAnalyzer { compiler: self.compiler, target: self.target })
+        {
+            install_sh(builder, "rust-analyzer", self.compiler.stage, Some(self.target), &tarball);
+        } else {
+            builder.info(
+                &format!("skipping Install rust-analyzer stage{} ({})", self.compiler.stage, self.target),
+            );
+        }
     };
     Clippy, "clippy", Self::should_build(_config), only_hosts: true, {
         let tarball = builder.ensure(dist::Clippy { compiler: self.compiler, target: self.target });

From cc9284d21db8a730707cb5a8694aaad25e11c232 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Sun, 11 Jul 2021 09:01:31 -0700
Subject: [PATCH 7/8] Add comments why install steps should never fail.

---
 src/bootstrap/install.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/bootstrap/install.rs b/src/bootstrap/install.rs
index 6f3054538a898..2ac9d3dda206f 100644
--- a/src/bootstrap/install.rs
+++ b/src/bootstrap/install.rs
@@ -139,11 +139,15 @@ macro_rules! install {
 
 install!((self, builder, _config),
     Docs, "src/doc", _config.docs, only_hosts: false, {
+        // `expect` should be safe, only None when config.docs is false,
+        // which is guarded in `should_run`
         let tarball = builder.ensure(dist::Docs { host: self.target }).expect("missing docs");
         install_sh(builder, "docs", self.compiler.stage, Some(self.target), &tarball);
     };
     Std, "library/std", true, only_hosts: false, {
         for target in &builder.targets {
+            // `expect` should be safe, only None when host != build, but this
+            // only runs when host == build
             let tarball = builder.ensure(dist::Std {
                 compiler: self.compiler,
                 target: *target
@@ -217,6 +221,8 @@ install!((self, builder, _config),
         }
     };
     Analysis, "analysis", Self::should_build(_config), only_hosts: false, {
+        // `expect` should be safe, only None with host != build, but this
+        // only uses the `build` compiler
         let tarball = builder.ensure(dist::Analysis {
             // Find the actual compiler (handling the full bootstrap option) which
             // produced the save-analysis data because that data isn't copied

From c8b3431be195b3b07a687aa08e285b014eaf6077 Mon Sep 17 00:00:00 2001
From: Eric Huss <eric@huss.org>
Date: Mon, 12 Jul 2021 13:29:47 -0700
Subject: [PATCH 8/8] Provide a better error when `x.py install src/doc`
 doesn't work.

---
 src/bootstrap/install.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/bootstrap/install.rs b/src/bootstrap/install.rs
index 2ac9d3dda206f..8a1b6df0dafe3 100644
--- a/src/bootstrap/install.rs
+++ b/src/bootstrap/install.rs
@@ -139,10 +139,12 @@ macro_rules! install {
 
 install!((self, builder, _config),
     Docs, "src/doc", _config.docs, only_hosts: false, {
-        // `expect` should be safe, only None when config.docs is false,
-        // which is guarded in `should_run`
-        let tarball = builder.ensure(dist::Docs { host: self.target }).expect("missing docs");
-        install_sh(builder, "docs", self.compiler.stage, Some(self.target), &tarball);
+        if let Some(tarball) = builder.ensure(dist::Docs { host: self.target }) {
+            install_sh(builder, "docs", self.compiler.stage, Some(self.target), &tarball);
+        } else {
+            panic!("docs are not available to install, \
+                check that `build.docs` is true in `config.toml`");
+        }
     };
     Std, "library/std", true, only_hosts: false, {
         for target in &builder.targets {