Replace is_range_full with is_full_collection_range (#17213)

Based on #17212

This was only ever used for collections and the extra work it did was
incorrect for that use case. This will no longer const eval the start,
but we shouldn't doing that on style lints anyways.

changelog: none

Author: llogiq

clippy_lints/src/methods/clear_with_drain.rs

@@ -1,8 +1,8 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::res::MaybeDef;
-use clippy_utils::{is_range_full, sym};
+use clippy_utils::res::{MaybeDef, MaybeResPath};
+use clippy_utils::{is_full_collection_range, sym};
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, LangItem, QPath};
+use rustc_hir::{Expr, LangItem};
 use rustc_lint::LateContext;
 use rustc_span::Span;
 
@@ -16,8 +16,7 @@ const ACCEPTABLE_TYPES_WITHOUT_ARG: [rustc_span::Symbol; 3] = [sym::BinaryHeap,
 pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, recv: &Expr<'_>, span: Span, arg: Option<&Expr<'_>>) {
     if let Some(arg) = arg {
         if match_acceptable_type(cx, recv, &ACCEPTABLE_TYPES_WITH_ARG)
-            && let ExprKind::Path(QPath::Resolved(None, container_path)) = recv.kind
-            && is_range_full(cx, arg, Some(container_path))
+            && is_full_collection_range(cx, recv.res_local_id(), arg)
         {
             suggest(cx, expr, recv, span);
         }

clippy_lints/src/methods/drain_collect.rs

@@ -1,10 +1,10 @@
 use crate::methods::DRAIN_COLLECT;
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::res::MaybeDef;
+use clippy_utils::res::{MaybeDef, MaybeResPath};
 use clippy_utils::source::snippet;
-use clippy_utils::{is_range_full, std_or_core, sym};
+use clippy_utils::{is_full_collection_range, std_or_core, sym};
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, QPath};
+use rustc_hir::Expr;
 use rustc_lint::LateContext;
 use rustc_middle::ty;
 
@@ -21,13 +21,7 @@ pub(super) fn check(cx: &LateContext<'_>, arg: Option<&Expr<'_>>, expr: &Expr<'_
                 ty.opt_diag_name(cx),
                 Some(sym::HashMap | sym::HashSet | sym::BinaryHeap | sym::Vec | sym::VecDeque)
             ))
-        && arg.is_none_or(|arg| {
-            if let ExprKind::Path(QPath::Resolved(None, path)) = recv.kind {
-                is_range_full(cx, arg, Some(path))
-            } else {
-                false
-            }
-        })
+        && arg.is_none_or(|arg| is_full_collection_range(cx, recv.res_local_id(), arg))
         && let Some(exec_context) = std_or_core(cx)
     {
         let recv = snippet(cx, recv.span, "<expr>");

clippy_lints/src/methods/iter_with_drain.rs

@@ -1,7 +1,8 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::{is_range_full, sym};
+use clippy_utils::res::MaybeResPath;
+use clippy_utils::{is_full_collection_range, sym};
 use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind, QPath};
+use rustc_hir::{Expr, ExprKind};
 use rustc_lint::LateContext;
 use rustc_span::Span;
 
@@ -12,8 +13,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, recv: &Expr<'_>, span
         && let Some(adt) = cx.typeck_results().expr_ty(recv).ty_adt_def()
         && let Some(ty_name) = cx.tcx.get_diagnostic_name(adt.did())
         && matches!(ty_name, sym::Vec | sym::VecDeque)
-        && let ExprKind::Path(QPath::Resolved(None, container_path)) = recv.kind
-        && is_range_full(cx, arg, Some(container_path))
+        && is_full_collection_range(cx, recv.res_local_id(), arg)
     {
         span_lint_and_sugg(
             cx,

clippy_utils/src/lib.rs

@@ -120,7 +120,6 @@ use source::{SpanExt, walk_span_to_context};
 use visitors::{Visitable, for_each_unconsumed_temporary};
 
 use crate::ast_utils::unordered_over;
-use crate::consts::ConstEvalCtxt;
 use crate::higher::Range;
 use crate::msrvs::Msrv;
 use crate::res::{MaybeDef, MaybeQPath, MaybeResPath};
@@ -1330,59 +1329,23 @@ pub fn is_else_clause_in_let_else(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
     })
 }
 
-/// Checks whether the given `Expr` is a range equivalent to a `RangeFull`.
-///
-/// For the lower bound, this means that:
-/// - either there is none
-/// - or it is the smallest value that can be represented by the range's integer type
-///
-/// For the upper bound, this means that:
-/// - either there is none
-/// - or it is the largest value that can be represented by the range's integer type and is
-///   inclusive
-/// - or it is a call to some container's `len` method and is exclusive, and the range is passed to
-///   a method call on that same container (e.g. `v.drain(..v.len())`)
-///
-/// If the given `Expr` is not some kind of range, the function returns `false`.
-pub fn is_range_full(cx: &LateContext<'_>, expr: &Expr<'_>, container_path: Option<&Path<'_>>) -> bool {
-    let ty = cx.typeck_results().expr_ty(expr);
+/// Checks whether the given `Expr` is a range over the entire container.
+pub fn is_full_collection_range(cx: &LateContext<'_>, container: Option<HirId>, expr: &Expr<'_>) -> bool {
     if let Some(Range { start, end, limits, .. }) = Range::hir(cx, expr) {
-        let start_is_none_or_min = start.is_none_or(|start| {
-            if let rustc_ty::Adt(_, subst) = ty.kind()
-                && let bnd_ty = subst.type_at(0)
-                && let Some(start_const) = ConstEvalCtxt::new(cx).eval(start)
-            {
-                start_const.is_numeric_min(cx.tcx, bnd_ty)
-            } else {
-                false
-            }
-        });
-        let end_is_none_or_max = end.is_none_or(|end| match limits {
-            RangeLimits::Closed => {
-                if let rustc_ty::Adt(_, subst) = ty.kind()
-                    && let bnd_ty = subst.type_at(0)
-                    && let Some(end_const) = ConstEvalCtxt::new(cx).eval(end)
+        start.is_none_or(|start| is_integer_literal(start, 0))
+            && end.is_none_or(|end| {
+                if limits == RangeLimits::HalfOpen
+                    && let Some(container) = container
+                    && let ExprKind::MethodCall(seg, recv, [], _) = end.kind
                 {
-                    end_const.is_numeric_max(cx.tcx, bnd_ty)
+                    seg.ident.name == sym::len && recv.res_local_id() == Some(container)
                 } else {
                     false
                 }
-            },
-            RangeLimits::HalfOpen => {
-                if let Some(container_path) = container_path
-                    && let ExprKind::MethodCall(name, self_arg, [], _) = end.kind
-                    && name.ident.name == sym::len
-                    && let ExprKind::Path(QPath::Resolved(None, path)) = self_arg.kind
-                {
-                    container_path.res == path.res
-                } else {
-                    false
-                }
-            },
-        });
-        return start_is_none_or_min && end_is_none_or_max;
+            })
+    } else {
+        false
     }
-    false
 }
 
 /// Checks whether the given expression is a constant literal of the given value.

tests/ui/clear_with_drain.fixed

@@ -20,11 +20,6 @@ fn vec_range() {
     let mut v = vec![1, 2, 3];
     v.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut v = vec![1, 2, 3];
-    v.clear();
-    //~^ clear_with_drain
 }
 
 fn vec_range_from() {
@@ -45,11 +40,6 @@ fn vec_range_from() {
     let mut v = vec![1, 2, 3];
     v.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut v = vec![1, 2, 3];
-    v.clear();
-    //~^ clear_with_drain
 }
 
 fn vec_range_full() {
@@ -124,11 +114,6 @@ fn vec_deque_range() {
     let mut deque = VecDeque::from([1, 2, 3]);
     deque.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut deque = VecDeque::from([1, 2, 3]);
-    deque.clear();
-    //~^ clear_with_drain
 }
 
 fn vec_deque_range_from() {
@@ -149,11 +134,6 @@ fn vec_deque_range_from() {
     let mut deque = VecDeque::from([1, 2, 3]);
     deque.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut deque = VecDeque::from([1, 2, 3]);
-    deque.clear();
-    //~^ clear_with_drain
 }
 
 fn vec_deque_range_full() {
@@ -228,11 +208,6 @@ fn string_range() {
     let mut s = String::from("Hello, world!");
     s.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut s = String::from("Hello, world!");
-    s.clear();
-    //~^ clear_with_drain
 }
 
 fn string_range_from() {
@@ -253,11 +228,6 @@ fn string_range_from() {
     let mut s = String::from("Hello, world!");
     s.clear();
     //~^ clear_with_drain
-
-    // Do lint
-    let mut s = String::from("Hello, world!");
-    s.clear();
-    //~^ clear_with_drain
 }
 
 fn string_range_full() {

tests/ui/clear_with_drain.rs

@@ -20,11 +20,6 @@ fn vec_range() {
     let mut v = vec![1, 2, 3];
     v.drain(0..v.len());
     //~^ clear_with_drain
-
-    // Do lint
-    let mut v = vec![1, 2, 3];
-    v.drain(usize::MIN..v.len());
-    //~^ clear_with_drain
 }
 
 fn vec_range_from() {
@@ -45,11 +40,6 @@ fn vec_range_from() {
     let mut v = vec![1, 2, 3];
     v.drain(0..);
     //~^ clear_with_drain
-
-    // Do lint
-    let mut v = vec![1, 2, 3];
-    v.drain(usize::MIN..);
-    //~^ clear_with_drain
 }
 
 fn vec_range_full() {
@@ -124,11 +114,6 @@ fn vec_deque_range() {
     let mut deque = VecDeque::from([1, 2, 3]);
     deque.drain(0..deque.len());
     //~^ clear_with_drain
-
-    // Do lint
-    let mut deque = VecDeque::from([1, 2, 3]);
-    deque.drain(usize::MIN..deque.len());
-    //~^ clear_with_drain
 }
 
 fn vec_deque_range_from() {
@@ -149,11 +134,6 @@ fn vec_deque_range_from() {
     let mut deque = VecDeque::from([1, 2, 3]);
     deque.drain(0..);
     //~^ clear_with_drain
-
-    // Do lint
-    let mut deque = VecDeque::from([1, 2, 3]);
-    deque.drain(usize::MIN..);
-    //~^ clear_with_drain
 }
 
 fn vec_deque_range_full() {
@@ -228,11 +208,6 @@ fn string_range() {
     let mut s = String::from("Hello, world!");
     s.drain(0..s.len());
     //~^ clear_with_drain
-
-    // Do lint
-    let mut s = String::from("Hello, world!");
-    s.drain(usize::MIN..s.len());
-    //~^ clear_with_drain
 }
 
 fn string_range_from() {
@@ -253,11 +228,6 @@ fn string_range_from() {
     let mut s = String::from("Hello, world!");
     s.drain(0..);
     //~^ clear_with_drain
-
-    // Do lint
-    let mut s = String::from("Hello, world!");
-    s.drain(usize::MIN..);
-    //~^ clear_with_drain
 }
 
 fn string_range_full() {