Auto merge of rust-lang#60167 - varkor:tidy-filelength, r=matthewjasper

Add a tidy check for files with over 3,000 lines

Files with a large number of lines can cause issues in GitHub (e.g. rust-lang#60015) and also tend to be indicative of opportunities to refactor into less monolithic structures.

This adds a new check to tidy to warn against files that have more than 3,000 lines, as suggested in rust-lang#60015 (comment). (This number was chosen fairly arbitrarily as a reasonable indicator of size.) This check can be ignored with `// ignore-tidy-filelength`.

Existing files with greater than 3,000 lines currently ignore the check, but this helps us spot when files are getting too large. (We might try to split up all files larger than this in the future, as in rust-lang#60015).

Author: bors

src/liballoc/collections/vec_deque.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! A double-ended queue implemented with a growable ring buffer.
 //!
 //! This queue has `O(1)` amortized inserts and removals from both ends of the

src/libcore/num/mod.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Numeric traits and functions for the built-in numeric types.
 
 #![stable(feature = "rust1", since = "1.0.0")]

src/libcore/ptr.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Manually manage memory through raw pointers.
 //!
 //! *[See also the pointer primitive types](../../std/primitive.pointer.html).*

src/libcore/slice/mod.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Slice management and manipulation.
 //!
 //! For more details see [`std::slice`].

src/libcore/str/mod.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! String manipulation.
 //!
 //! For more details, see the `std::str` module.

src/librustc/hir/lowering.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Lowers the AST to the HIR.
 //!
 //! Since the AST and HIR are fairly similar, this is mostly a simple procedure,

src/librustc/mir/mod.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! MIR datatypes and passes. See the [rustc guide] for more info.
 //!
 //! [rustc guide]: https://rust-lang.github.io/rustc-guide/mir/index.html

src/librustc/session/config.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Contains infrastructure for configuring the compiler, including parsing
 //! command line options.
 

src/librustc/traits/select.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Candidate selection. See the [rustc guide] for more information on how this works.
 //!
 //! [rustc guide]: https://rust-lang.github.io/rustc-guide/traits/resolution.html#selection

src/librustc/ty/context.rs

@@ -1,3 +1,5 @@
+// ignore-tidy-filelength
+
 //! Type context book-keeping.
 
 use crate::arena::Arena;