Follow review comments (optimize the filtering)

6 files changed, 97 insertions, 29 deletions

diff --git a/clippy_lints/src/asm_syntax.rs b/clippy_lints/src/asm_syntax.rs
index 9f3c24a9e80..69a8eb7d94e 100644
--- a/clippy_lints/src/asm_syntax.rs
+++ b/clippy_lints/src/asm_syntax.rs
@@ -3,7 +3,7 @@ use std::fmt;
 use clippy_utils::diagnostics::span_lint_and_then;
 use rustc_ast::ast::{Expr, ExprKind, InlineAsmOptions};
 use rustc_ast::{InlineAsm, Item, ItemKind};
-use rustc_lint::{EarlyContext, EarlyLintPass, Lint, LintPass, LintContext};
+use rustc_lint::{EarlyContext, EarlyLintPass, Lint, LintContext};
 use rustc_session::declare_lint_pass;
 use rustc_span::Span;
 use rustc_target::asm::InlineAsmArch;
diff --git a/clippy_lints/src/cognitive_complexity.rs b/clippy_lints/src/cognitive_complexity.rs
index 495d8ce3fa7..b027c289a7f 100644
--- a/clippy_lints/src/cognitive_complexity.rs
+++ b/clippy_lints/src/cognitive_complexity.rs
@@ -8,30 +8,44 @@ use core::ops::ControlFlow;
 use rustc_ast::ast::Attribute;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{Body, Expr, ExprKind, FnDecl};
-use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_lint::Level::Allow;
+use rustc_lint::{LateContext, LateLintPass, Lint, LintContext};
 use rustc_session::impl_lint_pass;
 use rustc_span::def_id::LocalDefId;
 use rustc_span::{Span, sym};
 
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for methods with high cognitive complexity.
-    ///
-    /// ### Why is this bad?
-    /// Methods of high cognitive complexity tend to be hard to
-    /// both read and maintain. Also LLVM will tend to optimize small methods better.
-    ///
-    /// ### Known problems
-    /// Sometimes it's hard to find a way to reduce the
-    /// complexity.
-    ///
-    /// ### Example
-    /// You'll see it when you get the warning.
-    #[clippy::version = "1.35.0"]
-    pub COGNITIVE_COMPLEXITY,
-    nursery,
-    "functions that should be split up into multiple functions"
-}
+use crate::LintInfo;
+
+pub static COGNITIVE_COMPLEXITY: &Lint = &Lint {
+    name: &"clippy::COGNITIVE_COMPLEXITY",
+    default_level: Allow,
+    desc: "functions that should be split up into multiple functions",
+    edition_lint_opts: None,
+    report_in_external_macro: true,
+    future_incompatible: None,
+    is_externally_loaded: true,
+    crate_level_only: false,
+    loadbearing: true,
+    ..Lint::default_fields_for_macro()
+};
+pub(crate) static COGNITIVE_COMPLEXITY_INFO: &'static LintInfo = &LintInfo {
+    lint: &COGNITIVE_COMPLEXITY,
+    category: crate::LintCategory::Nursery,
+    explanation: r"### What it does
+Checks for methods with high cognitive complexity.
+
+### Why is this bad?
+Methods of high cognitive complexity tend to be hard to both read and maintain.
+Also LLVM will tend to optimize small methods better.
+
+### Known problems
+Sometimes it's hard to find a way to reduce the complexity.
+
+### Example
+You'll see it when you get the warning.",
+    version: Some("1.35.0"),
+    location: "#L0",
+};
 
 pub struct CognitiveComplexity {
     limit: LimitStack,
diff --git a/clippy_lints/src/ctfe.rs b/clippy_lints/src/ctfe.rs
new file mode 100644
index 00000000000..7b9f71810a9
--- /dev/null
+++ b/clippy_lints/src/ctfe.rs
@@ -0,0 +1,54 @@
+use rustc_hir::def_id::LocalDefId;
+use rustc_hir::intravisit::FnKind;
+use rustc_hir::{Body, FnDecl};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::declare_lint_pass;
+use rustc_span::Span;
+
+declare_clippy_lint! {
+    /// ### What it does
+    /// Checks for comparisons where one side of the relation is
+    /// either the minimum or maximum value for its type and warns if it involves a
+    /// case that is always true or always false. Only integer and boolean types are
+    /// checked.
+    ///
+    /// ### Why is this bad?
+    /// An expression like `min <= x` may misleadingly imply
+    /// that it is possible for `x` to be less than the minimum. Expressions like
+    /// `max < x` are probably mistakes.
+    ///
+    /// ### Known problems
+    /// For `usize` the size of the current compile target will
+    /// be assumed (e.g., 64 bits on 64 bit systems). This means code that uses such
+    /// a comparison to detect target pointer width will trigger this lint. One can
+    /// use `mem::sizeof` and compare its value or conditional compilation
+    /// attributes
+    /// like `#[cfg(target_pointer_width = "64")] ..` instead.
+    ///
+    /// ### Example
+    /// ```no_run
+    /// let vec: Vec<isize> = Vec::new();
+    /// if vec.len() <= 0 {}
+    /// if 100 > i32::MAX {}
+    /// ```
+    #[clippy::version = "1.82.0"]
+    pub CLIPPY_CTFE,
+    correctness,
+    "a comparison with a maximum or minimum value that is always true or false"
+}
+
+declare_lint_pass! { ClippyCtfe => [CLIPPY_CTFE] }
+
+impl<'tcx> LateLintPass<'tcx> for ClippyCtfe {
+    fn check_fn(
+        &mut self,
+        cx: &LateContext<'_>,
+        _: FnKind<'tcx>,
+        _: &'tcx FnDecl<'tcx>,
+        _: &'tcx Body<'tcx>,
+        _: Span,
+        defid: LocalDefId,
+    ) {
+        cx.tcx.ensure().mir_drops_elaborated_and_const_checked(defid); // Lint
+    }
+}
diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs
index 6e29dde2211..a5d2f6a4122 100644
--- a/clippy_lints/src/lib.rs
+++ b/clippy_lints/src/lib.rs
@@ -65,6 +65,7 @@ extern crate clippy_utils;
 #[cfg_attr(feature = "internal", allow(clippy::missing_clippy_version_attribute))]
 mod utils;
 
+pub mod ctfe; // VERY important lint (rust#125116)
 pub mod declared_lints;
 pub mod deprecated_lints;
 
@@ -605,6 +606,8 @@ pub fn register_lints(store: &mut rustc_lint::LintStore, conf: &'static Conf) {
         });
     }
 
+    store.register_late_pass(|_| Box::new(ctfe::ClippyCtfe));
+
     store.register_late_pass(move |_| Box::new(operators::arithmetic_side_effects::ArithmeticSideEffects::new(conf)));
     store.register_late_pass(|_| Box::new(utils::dump_hir::DumpHir));
     store.register_late_pass(|_| Box::new(utils::author::Author));
diff --git a/clippy_lints/src/utils/internal_lints/author.rs b/clippy_lints/src/utils/author.rs
index 0ed606a836e..f4e166327af 100644
--- a/clippy_lints/src/utils/internal_lints/author.rs
+++ b/clippy_lints/src/utils/author.rs
@@ -12,7 +12,7 @@ use rustc_span::symbol::{Ident, Symbol};
 use std::cell::Cell;
 use std::fmt::{Display, Formatter, Write as _};
 
-declare_clippy_lint!{
+declare_lint_pass!(
     /// ### What it does
     /// Generates clippy code that detects the offending pattern
     ///
@@ -44,13 +44,8 @@ declare_clippy_lint!{
     ///     // report your lint here
     /// }
     /// ```
-    #[clippy::version = "1.0.0"]
-    pub AUTHOR,
-    internal,
-    "The author lint, see documentation at <https://doc.rust-lang.org/nightly/clippy/development/adding_lints.html#author-lint>"
-};
-
-declare_lint_pass! { Author => [AUTHOR] }
+    Author => []
+);
 
 /// Writes a line of output with indentation added
 macro_rules! out {
@@ -803,3 +798,4 @@ fn path_to_string(path: &QPath<'_>) -> Result<String, ()> {
     inner(&mut s, path)?;
     Ok(s)
 }
+
diff --git a/clippy_lints/src/utils/mod.rs b/clippy_lints/src/utils/mod.rs
index abd10ac024c..13e9ead9a57 100644
--- a/clippy_lints/src/utils/mod.rs
+++ b/clippy_lints/src/utils/mod.rs
@@ -1,3 +1,4 @@
+pub mod author;
 pub mod dump_hir;
 pub mod format_args_collector;
 #[cfg(feature = "internal")]