Auto merge of #11859 - y21:issue11856, r=blyxyas

[`missing_asserts_for_indexing`]: work with bodies instead of blocks separately

Fixes #11856

Before this change, this lint would check blocks independently of each other, which means that it misses `assert!()`s from parent blocks.
```rs
// check_block
assert!(x.len() > 1);

{
  // check_block
  // no assert here
  let _ = x[0] + x[1];
}
```

This PR changes it to work with bodies rather than individual blocks. That means that a function will be checked in one go and we can remember if an `assert!` occurred anywhere.

Eventually it would be nice to have a more control flow-aware analysis, possibly by rewriting it as a MIR lint, but that's more complicated and I wanted this fixed first.

changelog: [`missing_asserts_for_indexing`]: accept `assert!`s from parent blocks

1 files changed, 3 insertions, 3 deletions

diff --git a/clippy_lints/src/missing_asserts_for_indexing.rs b/clippy_lints/src/missing_asserts_for_indexing.rs
index ff2792faf57..5d6dc8d5582 100644
--- a/clippy_lints/src/missing_asserts_for_indexing.rs
+++ b/clippy_lints/src/missing_asserts_for_indexing.rs
@@ -9,7 +9,7 @@ use clippy_utils::{eq_expr_value, hash_expr, higher};
 use rustc_ast::{LitKind, RangeLimits};
 use rustc_data_structures::unhash::UnhashMap;
 use rustc_errors::{Applicability, Diagnostic};
-use rustc_hir::{BinOp, Block, Expr, ExprKind, UnOp};
+use rustc_hir::{BinOp, Block, Body, Expr, ExprKind, UnOp};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::Spanned;
@@ -390,10 +390,10 @@ fn report_indexes(cx: &LateContext<'_>, map: &UnhashMap<u64, Vec<IndexEntry<'_>>
 }
 
 impl LateLintPass<'_> for MissingAssertsForIndexing {
-    fn check_block(&mut self, cx: &LateContext<'_>, block: &Block<'_>) {
+    fn check_body(&mut self, cx: &LateContext<'_>, body: &Body<'_>) {
         let mut map = UnhashMap::default();
 
-        for_each_expr(block, |expr| {
+        for_each_expr(body.value, |expr| {
             check_index(cx, expr, &mut map);
             check_assert(cx, expr, &mut map);
             ControlFlow::<!, ()>::Continue(())