Improve spans for indexing expressions

Indexing is similar to method calls in having an arbitrary
left-hand-side and then something on the right, which is the main part
of the expression. Method calls already have a span for that right part,
but indexing does not. This means that long method chains that use
indexing have really bad spans, especially when the indexing panics and
that span in coverted into a panic location.

This does the same thing as method calls for the AST and HIR, storing an
extra span which is then put into the `fn_span` field in THIR.

8 files changed, 11 insertions, 11 deletions

diff --git a/clippy_utils/src/ast_utils.rs b/clippy_utils/src/ast_utils.rs
index 7e42924603a..2d0d6f559ad 100644
--- a/clippy_utils/src/ast_utils.rs
+++ b/clippy_utils/src/ast_utils.rs
@@ -178,7 +178,7 @@ pub fn eq_expr(l: &Expr, r: &Expr) -> bool {
         (Yield(l), Yield(r)) | (Ret(l), Ret(r)) => eq_expr_opt(l, r),
         (Break(ll, le), Break(rl, re)) => eq_label(ll, rl) && eq_expr_opt(le, re),
         (Continue(ll), Continue(rl)) => eq_label(ll, rl),
-        (Assign(l1, l2, _), Assign(r1, r2, _)) | (Index(l1, l2), Index(r1, r2)) => eq_expr(l1, r1) && eq_expr(l2, r2),
+        (Assign(l1, l2, _), Assign(r1, r2, _)) | (Index(l1, l2, _), Index(r1, r2, _)) => eq_expr(l1, r1) && eq_expr(l2, r2),
         (AssignOp(lo, lp, lv), AssignOp(ro, rp, rv)) => lo.node == ro.node && eq_expr(lp, rp) && eq_expr(lv, rv),
         (Field(lp, lf), Field(rp, rf)) => eq_id(*lf, *rf) && eq_expr(lp, rp),
         (Match(ls, la), Match(rs, ra)) => eq_expr(ls, rs) && over(la, ra, eq_arm),
diff --git a/clippy_utils/src/check_proc_macro.rs b/clippy_utils/src/check_proc_macro.rs
index 89f8a65c5ae..60fab1ec41a 100644
--- a/clippy_utils/src/check_proc_macro.rs
+++ b/clippy_utils/src/check_proc_macro.rs
@@ -163,7 +163,7 @@ fn expr_search_pat(tcx: TyCtxt<'_>, e: &Expr<'_>) -> (Pat, Pat) {
         ) => (Pat::Str("unsafe"), Pat::Str("}")),
         ExprKind::Block(_, None) => (Pat::Str("{"), Pat::Str("}")),
         ExprKind::Field(e, name) => (expr_search_pat(tcx, e).0, Pat::Sym(name.name)),
-        ExprKind::Index(e, _) => (expr_search_pat(tcx, e).0, Pat::Str("]")),
+        ExprKind::Index(e, _, _) => (expr_search_pat(tcx, e).0, Pat::Str("]")),
         ExprKind::Path(ref path) => qpath_search_pat(path),
         ExprKind::AddrOf(_, _, e) => (Pat::Str("&"), expr_search_pat(tcx, e).1),
         ExprKind::Break(Destination { label: None, .. }, None) => (Pat::Str("break"), Pat::Str("break")),
diff --git a/clippy_utils/src/consts.rs b/clippy_utils/src/consts.rs
index f19e09a18ec..d38e3f1ae76 100644
--- a/clippy_utils/src/consts.rs
+++ b/clippy_utils/src/consts.rs
@@ -394,7 +394,7 @@ impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
                     }
                 }
             },
-            ExprKind::Index(arr, index) => self.index(arr, index),
+            ExprKind::Index(arr, index, _) => self.index(arr, index),
             ExprKind::AddrOf(_, _, inner) => self.expr(inner).map(|r| Constant::Ref(Box::new(r))),
             ExprKind::Field(local_expr, ref field) => {
                 let result = self.expr(local_expr);
diff --git a/clippy_utils/src/eager_or_lazy.rs b/clippy_utils/src/eager_or_lazy.rs
index 3c969572b8e..0bcefba75a7 100644
--- a/clippy_utils/src/eager_or_lazy.rs
+++ b/clippy_utils/src/eager_or_lazy.rs
@@ -185,7 +185,7 @@ fn expr_eagerness<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) -> EagernessS
                         .type_dependent_def_id(e.hir_id)
                         .map_or(Lazy, |id| fn_eagerness(self.cx, id, name.ident.name, true));
                 },
-                ExprKind::Index(_, e) => {
+                ExprKind::Index(_, e, _) => {
                     let ty = self.cx.typeck_results().expr_ty_adjusted(e);
                     if is_copy(self.cx, ty) && !ty.is_ref() {
                         self.eagerness |= NoChange;
diff --git a/clippy_utils/src/hir_utils.rs b/clippy_utils/src/hir_utils.rs
index 85b3b005f93..fdc35cd4ddf 100644
--- a/clippy_utils/src/hir_utils.rs
+++ b/clippy_utils/src/hir_utils.rs
@@ -299,7 +299,7 @@ impl HirEqInterExpr<'_, '_, '_> {
             (&ExprKind::Field(l_f_exp, ref l_f_ident), &ExprKind::Field(r_f_exp, ref r_f_ident)) => {
                 l_f_ident.name == r_f_ident.name && self.eq_expr(l_f_exp, r_f_exp)
             },
-            (&ExprKind::Index(la, li), &ExprKind::Index(ra, ri)) => self.eq_expr(la, ra) && self.eq_expr(li, ri),
+            (&ExprKind::Index(la, li, _), &ExprKind::Index(ra, ri, _)) => self.eq_expr(la, ra) && self.eq_expr(li, ri),
             (&ExprKind::If(lc, lt, ref le), &ExprKind::If(rc, rt, ref re)) => {
                 self.eq_expr(lc, rc) && self.eq_expr(lt, rt) && both(le, re, |l, r| self.eq_expr(l, r))
             },
@@ -730,7 +730,7 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
                 self.hash_expr(e);
                 self.hash_name(f.name);
             },
-            ExprKind::Index(a, i) => {
+            ExprKind::Index(a, i, _) => {
                 self.hash_expr(a);
                 self.hash_expr(i);
             },
diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs
index cf30930b76e..4cd8a8c3325 100644
--- a/clippy_utils/src/lib.rs
+++ b/clippy_utils/src/lib.rs
@@ -735,7 +735,7 @@ fn projection_stack<'a, 'hir>(mut e: &'a Expr<'hir>) -> (Vec<&'a Expr<'hir>>, &'
     let mut result = vec![];
     let root = loop {
         match e.kind {
-            ExprKind::Index(ep, _) | ExprKind::Field(ep, _) => {
+            ExprKind::Index(ep, _, _) | ExprKind::Field(ep, _) => {
                 result.push(e);
                 e = ep;
             },
@@ -782,7 +782,7 @@ pub fn can_mut_borrow_both(cx: &LateContext<'_>, e1: &Expr<'_>, e2: &Expr<'_>) -
                     return true;
                 }
             },
-            (ExprKind::Index(_, i1), ExprKind::Index(_, i2)) => {
+            (ExprKind::Index(_, i1, _), ExprKind::Index(_, i2, _)) => {
                 if !eq_expr_value(cx, i1, i2) {
                     return false;
                 }
diff --git a/clippy_utils/src/ty/type_certainty/mod.rs b/clippy_utils/src/ty/type_certainty/mod.rs
index 45b5483e323..0669ea72eb3 100644
--- a/clippy_utils/src/ty/type_certainty/mod.rs
+++ b/clippy_utils/src/ty/type_certainty/mod.rs
@@ -31,7 +31,7 @@ fn expr_type_certainty(cx: &LateContext<'_>, expr: &Expr<'_>) -> Certainty {
     let certainty = match &expr.kind {
         ExprKind::Unary(_, expr)
         | ExprKind::Field(expr, _)
-        | ExprKind::Index(expr, _)
+        | ExprKind::Index(expr, _, _)
         | ExprKind::AddrOf(_, _, expr) => expr_type_certainty(cx, expr),
 
         ExprKind::Array(exprs) => join(exprs.iter().map(|expr| expr_type_certainty(cx, expr))),
diff --git a/clippy_utils/src/visitors.rs b/clippy_utils/src/visitors.rs
index 09f447b27eb..f83988a6e32 100644
--- a/clippy_utils/src/visitors.rs
+++ b/clippy_utils/src/visitors.rs
@@ -329,7 +329,7 @@ pub fn is_const_evaluatable<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) ->
                         && self.cx.typeck_results().expr_ty(rhs).peel_refs().is_primitive_ty() => {},
                 ExprKind::Unary(UnOp::Deref, e) if self.cx.typeck_results().expr_ty(e).is_ref() => (),
                 ExprKind::Unary(_, e) if self.cx.typeck_results().expr_ty(e).peel_refs().is_primitive_ty() => (),
-                ExprKind::Index(base, _)
+                ExprKind::Index(base, _, _)
                     if matches!(
                         self.cx.typeck_results().expr_ty(base).peel_refs().kind(),
                         ty::Slice(_) | ty::Array(..)
@@ -629,7 +629,7 @@ pub fn for_each_unconsumed_temporary<'tcx, B>(
                     helper(typeck, true, arg, f)?;
                 }
             },
-            ExprKind::Index(borrowed, consumed)
+            ExprKind::Index(borrowed, consumed, _)
             | ExprKind::Assign(borrowed, consumed, _)
             | ExprKind::AssignOp(_, borrowed, consumed) => {
                 helper(typeck, false, borrowed, f)?;