Auto merge of #68101 - JohnTitor:rollup-mvmjukr, r=JohnTitor

Rollup of 8 pull requests

Successful merges:

 - #66045 (Add method Result::into_ok)
 - #67258 (Introduce `X..`, `..X`, and `..=X` range patterns)
 - #68014 (Unify output of "variant not found" errors)
 - #68019 (Build compiletest with in-tree libtest)
 - #68039 (remove explicit strip-hidden pass from compiler doc generation)
 - #68050 (Canonicalize rustc_error imports)
 - #68059 (Allow specifying LLVM args in target specifications)
 - #68075 (rustbuild: Cleanup book generation)

Failed merges:

 - #68089 (Unstabilize `Vec::remove_item`)

r? @ghost

Author: bors

Diff for: Cargo.lock

@@ -3654,6 +3654,7 @@ dependencies = [
  "log",
  "rustc",
  "rustc_data_structures",
+ "rustc_errors",
  "rustc_feature",
  "rustc_hir",
  "rustc_index",

Diff for: src/bootstrap/doc.rs

@@ -49,7 +49,7 @@ macro_rules! book {
                 builder.ensure(RustbookSrc {
                     target: self.target,
                     name: INTERNER.intern_str($book_name),
-                    src: doc_src(builder),
+                    src: INTERNER.intern_path(builder.src.join($path)),
                 })
             }
         }
@@ -60,6 +60,7 @@ macro_rules! book {
 // NOTE: When adding a book here, make sure to ALSO build the book by
 // adding a build step in `src/bootstrap/builder.rs`!
 book!(
+    CargoBook, "src/tools/cargo/src/doc", "cargo";
     EditionGuide, "src/doc/edition-guide", "edition-guide";
     EmbeddedBook, "src/doc/embedded-book", "embedded-book";
     Nomicon, "src/doc/nomicon", "nomicon";
@@ -69,10 +70,6 @@ book!(
     RustdocBook, "src/doc/rustdoc", "rustdoc";
 );
 
-fn doc_src(builder: &Builder<'_>) -> Interned<PathBuf> {
-    INTERNER.intern_path(builder.src.join("src/doc"))
-}
-
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct UnstableBook {
     target: Interned<String>,
@@ -96,48 +93,11 @@ impl Step for UnstableBook {
         builder.ensure(RustbookSrc {
             target: self.target,
             name: INTERNER.intern_str("unstable-book"),
-            src: builder.md_doc_out(self.target),
+            src: INTERNER.intern_path(builder.md_doc_out(self.target).join("unstable-book")),
         })
     }
 }
 
-#[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
-pub struct CargoBook {
-    target: Interned<String>,
-    name: Interned<String>,
-}
-
-impl Step for CargoBook {
-    type Output = ();
-    const DEFAULT: bool = true;
-
-    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        let builder = run.builder;
-        run.path("src/tools/cargo/src/doc/book").default_condition(builder.config.docs)
-    }
-
-    fn make_run(run: RunConfig<'_>) {
-        run.builder.ensure(CargoBook { target: run.target, name: INTERNER.intern_str("cargo") });
-    }
-
-    fn run(self, builder: &Builder<'_>) {
-        let target = self.target;
-        let name = self.name;
-        let src = builder.src.join("src/tools/cargo/src/doc");
-
-        let out = builder.doc_out(target);
-        t!(fs::create_dir_all(&out));
-
-        let out = out.join(name);
-
-        builder.info(&format!("Cargo Book ({}) - {}", target, name));
-
-        let _ = fs::remove_dir_all(&out);
-
-        builder.run(builder.tool_cmd(Tool::Rustbook).arg("build").arg(&src).arg("-d").arg(out));
-    }
-}
-
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq)]
 struct RustbookSrc {
     target: Interned<String>,
@@ -164,7 +124,6 @@ impl Step for RustbookSrc {
         t!(fs::create_dir_all(&out));
 
         let out = out.join(name);
-        let src = src.join(name);
         let index = out.join("index.html");
         let rustbook = builder.tool_exe(Tool::Rustbook);
         let mut rustbook_cmd = builder.tool_cmd(Tool::Rustbook);
@@ -182,7 +141,6 @@ impl Step for RustbookSrc {
 pub struct TheBook {
     compiler: Compiler,
     target: Interned<String>,
-    name: &'static str,
 }
 
 impl Step for TheBook {
@@ -198,53 +156,37 @@ impl Step for TheBook {
         run.builder.ensure(TheBook {
             compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.build),
             target: run.target,
-            name: "book",
         });
     }
 
     /// Builds the book and associated stuff.
     ///
     /// We need to build:
     ///
-    /// * Book (first edition)
-    /// * Book (second edition)
+    /// * Book
+    /// * Older edition redirects
     /// * Version info and CSS
     /// * Index page
     /// * Redirect pages
     fn run(self, builder: &Builder<'_>) {
         let compiler = self.compiler;
         let target = self.target;
-        let name = self.name;
 
         // build book
         builder.ensure(RustbookSrc {
             target,
-            name: INTERNER.intern_string(name.to_string()),
-            src: doc_src(builder),
+            name: INTERNER.intern_str("book"),
+            src: INTERNER.intern_path(builder.src.join("src/doc/book")),
         });
 
         // building older edition redirects
-
-        let source_name = format!("{}/first-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
-
-        let source_name = format!("{}/second-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
-
-        let source_name = format!("{}/2018-edition", name);
-        builder.ensure(RustbookSrc {
-            target,
-            name: INTERNER.intern_string(source_name),
-            src: doc_src(builder),
-        });
+        for edition in &["first-edition", "second-edition", "2018-edition"] {
+            builder.ensure(RustbookSrc {
+                target,
+                name: INTERNER.intern_string(format!("book/{}", edition)),
+                src: INTERNER.intern_path(builder.src.join("src/doc/book").join(edition)),
+            });
+        }
 
         // build the version info page and CSS
         builder.ensure(Standalone { compiler, target });
@@ -531,7 +473,7 @@ impl Step for Rustc {
 
         // Build cargo command.
         let mut cargo = builder.cargo(compiler, Mode::Rustc, target, "doc");
-        cargo.env("RUSTDOCFLAGS", "--document-private-items --passes strip-hidden");
+        cargo.env("RUSTDOCFLAGS", "--document-private-items");
         compile::rustc_cargo(builder, &mut cargo, target);
 
         // Only include compiler crates, no dependencies of those, such as `libc`.

Diff for: src/bootstrap/tool.rs

@@ -289,8 +289,8 @@ fn rustbook_features() -> Vec<String> {
 macro_rules! bootstrap_tool {
     ($(
         $name:ident, $path:expr, $tool_name:expr
-        $(,llvm_tools = $llvm:expr)*
         $(,is_external_tool = $external:expr)*
+        $(,is_unstable_tool = $unstable:expr)*
         $(,features = $features:expr)*
         ;
     )+) => {
@@ -301,15 +301,6 @@ macro_rules! bootstrap_tool {
             )+
         }
 
-        impl Tool {
-            /// Whether this tool requires LLVM to run
-            pub fn uses_llvm_tools(&self) -> bool {
-                match self {
-                    $(Tool::$name => false $(|| $llvm)*,)+
-                }
-            }
-        }
-
         impl<'a> Builder<'a> {
             pub fn tool_exe(&self, tool: Tool) -> PathBuf {
                 match tool {
@@ -350,7 +341,12 @@ macro_rules! bootstrap_tool {
                     compiler: self.compiler,
                     target: self.target,
                     tool: $tool_name,
-                    mode: Mode::ToolBootstrap,
+                    mode: if false $(|| $unstable)* {
+                        // use in-tree libraries for unstable features
+                        Mode::ToolStd
+                    } else {
+                        Mode::ToolBootstrap
+                    },
                     path: $path,
                     is_optional_tool: false,
                     source_type: if false $(|| $external)* {
@@ -377,7 +373,7 @@ bootstrap_tool!(
     Tidy, "src/tools/tidy", "tidy";
     Linkchecker, "src/tools/linkchecker", "linkchecker";
     CargoTest, "src/tools/cargotest", "cargotest";
-    Compiletest, "src/tools/compiletest", "compiletest", llvm_tools = true;
+    Compiletest, "src/tools/compiletest", "compiletest", is_unstable_tool = true;
     BuildManifest, "src/tools/build-manifest", "build-manifest";
     RemoteTestClient, "src/tools/remote-test-client", "remote-test-client";
     RustInstaller, "src/tools/rust-installer", "fabricate", is_external_tool = true;

Diff for: src/libcore/result.rs

@@ -1092,6 +1092,44 @@ impl<T: Default, E> Result<T, E> {
     }
 }
 
+#[unstable(feature = "unwrap_infallible", reason = "newly added", issue = "61695")]
+impl<T, E: Into<!>> Result<T, E> {
+    /// Unwraps a result that can never be an [`Err`], yielding the content of the [`Ok`].
+    ///
+    /// Unlike [`unwrap`], this method is known to never panic on the
+    /// result types it is implemented for. Therefore, it can be used
+    /// instead of `unwrap` as a maintainability safeguard that will fail
+    /// to compile if the error type of the `Result` is later changed
+    /// to an error that can actually occur.
+    ///
+    /// [`Ok`]: enum.Result.html#variant.Ok
+    /// [`Err`]: enum.Result.html#variant.Err
+    /// [`unwrap`]: enum.Result.html#method.unwrap
+    ///
+    /// # Examples
+    ///
+    /// Basic usage:
+    ///
+    /// ```
+    /// # #![feature(never_type)]
+    /// # #![feature(unwrap_infallible)]
+    ///
+    /// fn only_good_news() -> Result<String, !> {
+    ///     Ok("this is fine".into())
+    /// }
+    ///
+    /// let s: String = only_good_news().into_ok();
+    /// println!("{}", s);
+    /// ```
+    #[inline]
+    pub fn into_ok(self) -> T {
+        match self {
+            Ok(x) => x,
+            Err(e) => e.into(),
+        }
+    }
+}
+
 #[unstable(feature = "inner_deref", reason = "newly added", issue = "50264")]
 impl<T: Deref, E> Result<T, E> {
     /// Converts from `Result<T, E>` (or `&Result<T, E>`) to `Result<&T::Target, &E>`.

Diff for: src/libcore/tests/lib.rs

@@ -40,6 +40,8 @@
 #![feature(slice_from_raw_parts)]
 #![feature(const_slice_from_raw_parts)]
 #![feature(const_raw_ptr_deref)]
+#![feature(never_type)]
+#![feature(unwrap_infallible)]
 
 extern crate test;
 

Diff for: src/libcore/tests/result.rs

@@ -183,6 +183,28 @@ pub fn test_unwrap_or_default() {
     assert_eq!(op2().unwrap_or_default(), 0);
 }
 
+#[test]
+pub fn test_into_ok() {
+    fn infallible_op() -> Result<isize, !> {
+        Ok(666)
+    }
+
+    assert_eq!(infallible_op().into_ok(), 666);
+
+    enum MyNeverToken {}
+    impl From<MyNeverToken> for ! {
+        fn from(never: MyNeverToken) -> ! {
+            match never {}
+        }
+    }
+
+    fn infallible_op2() -> Result<isize, MyNeverToken> {
+        Ok(667)
+    }
+
+    assert_eq!(infallible_op2().into_ok(), 667);
+}
+
 #[test]
 fn test_try() {
     fn try_result_some() -> Option<u8> {

Diff for: src/librustc/Cargo.toml

@@ -26,8 +26,8 @@ rustc_hir = { path = "../librustc_hir" }
 rustc_target = { path = "../librustc_target" }
 rustc_macros = { path = "../librustc_macros" }
 rustc_data_structures = { path = "../librustc_data_structures" }
+rustc_errors = { path = "../librustc_errors" }
 rustc_index = { path = "../librustc_index" }
-errors = { path = "../librustc_errors", package = "rustc_errors" }
 rustc_serialize = { path = "../libserialize", package = "serialize" }
 syntax = { path = "../libsyntax" }
 rustc_span = { path = "../librustc_span" }

Diff for: src/librustc/dep_graph/graph.rs

@@ -1,11 +1,11 @@
 use crate::ty::{self, TyCtxt};
-use errors::Diagnostic;
 use parking_lot::{Condvar, Mutex};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::profiling::QueryInvocationId;
 use rustc_data_structures::sharded::{self, Sharded};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::{AtomicU32, AtomicU64, Lock, Lrc, Ordering};
+use rustc_errors::Diagnostic;
 use rustc_index::vec::{Idx, IndexVec};
 use smallvec::SmallVec;
 use std::collections::hash_map::Entry;

Diff for: src/librustc/hir/check_attr.rs

@@ -9,8 +9,8 @@ use crate::lint::builtin::UNUSED_ATTRIBUTES;
 use crate::ty::query::Providers;
 use crate::ty::TyCtxt;
 
-use errors::struct_span_err;
 use rustc_error_codes::*;
+use rustc_errors::struct_span_err;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};

Diff for: src/librustc/infer/error_reporting/mod.rs

@@ -64,15 +64,13 @@ use crate::ty::{
     subst::{Subst, SubstsRef},
     Region, Ty, TyCtxt, TypeFoldable,
 };
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_error_codes::*;
+use rustc_errors::{pluralize, struct_span_err};
+use rustc_errors::{Applicability, DiagnosticBuilder, DiagnosticStyledString};
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
 use rustc_hir::Node;
-
-use errors::{
-    pluralize, struct_span_err, Applicability, DiagnosticBuilder, DiagnosticStyledString,
-};
-use rustc_data_structures::fx::{FxHashMap, FxHashSet};
-use rustc_error_codes::*;
 use rustc_span::{DesugaringKind, Pos, Span};
 use rustc_target::spec::abi;
 use std::{cmp, fmt};

Diff for: src/librustc/infer/error_reporting/need_type_info.rs

@@ -3,7 +3,7 @@ use crate::infer::type_variable::TypeVariableOriginKind;
 use crate::infer::InferCtxt;
 use crate::ty::print::Print;
 use crate::ty::{self, DefIdTree, Infer, Ty, TyVar};
-use errors::{struct_span_err, Applicability, DiagnosticBuilder};
+use rustc_errors::{struct_span_err, Applicability, DiagnosticBuilder};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Namespace};
 use rustc_hir::intravisit::{self, NestedVisitorMap, Visitor};
@@ -151,12 +151,12 @@ pub enum TypeAnnotationNeeded {
     E0284,
 }
 
-impl Into<errors::DiagnosticId> for TypeAnnotationNeeded {
-    fn into(self) -> errors::DiagnosticId {
+impl Into<rustc_errors::DiagnosticId> for TypeAnnotationNeeded {
+    fn into(self) -> rustc_errors::DiagnosticId {
         match self {
-            Self::E0282 => errors::error_code!(E0282),
-            Self::E0283 => errors::error_code!(E0283),
-            Self::E0284 => errors::error_code!(E0284),
+            Self::E0282 => rustc_errors::error_code!(E0282),
+            Self::E0283 => rustc_errors::error_code!(E0283),
+            Self::E0284 => rustc_errors::error_code!(E0284),
         }
     }
 }

Diff for: src/librustc/infer/error_reporting/nice_region_error/different_lifetimes.rs

@@ -5,8 +5,8 @@ use crate::infer::error_reporting::nice_region_error::util::AnonymousParamInfo;
 use crate::infer::error_reporting::nice_region_error::NiceRegionError;
 use crate::util::common::ErrorReported;
 
-use errors::struct_span_err;
 use rustc_error_codes::*;
+use rustc_errors::struct_span_err;
 
 impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
     /// Print the error message for lifetime errors when both the concerned regions are anonymous.