Don't trigger const_is_empty for inline const assertions

Author: alex-semenyuk

clippy_lints/src/methods/is_empty.rs

@@ -1,6 +1,7 @@
 use clippy_utils::consts::ConstEvalCtxt;
 use clippy_utils::diagnostics::span_lint;
-use clippy_utils::{find_binding_init, path_to_local};
+use clippy_utils::macros::{is_assert_macro, root_macro_call};
+use clippy_utils::{find_binding_init, get_parent_expr, is_inside_always_const_context, path_to_local};
 use rustc_hir::{Expr, HirId};
 use rustc_lint::{LateContext, LintContext};
 use rustc_middle::lint::in_external_macro;
@@ -14,6 +15,16 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &'_ Expr<'_>, receiver: &Expr<'_
     if in_external_macro(cx.sess(), expr.span) || !receiver.span.eq_ctxt(expr.span) {
         return;
     }
+    if let Some(parent) = get_parent_expr(cx, expr) {
+        if let Some(parent) = get_parent_expr(cx, parent) {
+            if is_inside_always_const_context(cx.tcx, expr.hir_id)
+                && let Some(macro_call) = root_macro_call(parent.span)
+                && is_assert_macro(cx, macro_call.def_id)
+            {
+                return;
+            }
+        }
+    }
     let init_expr = expr_or_init(cx, receiver);
     if !receiver.span.eq_ctxt(init_expr.span) {
         return;

tests/ui/const_is_empty.rs

@@ -171,3 +171,17 @@ fn constant_from_external_crate() {
     let _ = std::env::consts::EXE_EXTENSION.is_empty();
     // Do not lint, `exe_ext` comes from the `std` crate
 }
+
+fn issue_13106() {
+    const {
+        assert!(!NON_EMPTY_STR.is_empty());
+    }
+
+    const {
+        assert!(EMPTY_STR.is_empty());
+    }
+
+    const {
+        EMPTY_STR.is_empty();
+    }
+}

tests/ui/const_is_empty.stderr

@@ -157,5 +157,11 @@ error: this expression always evaluates to true
 LL |     let _ = val.is_empty();
    |             ^^^^^^^^^^^^^^
 
-error: aborting due to 26 previous errors
+error: this expression always evaluates to true
+  --> tests/ui/const_is_empty.rs:185:9
+   |
+LL |         EMPTY_STR.is_empty();
+   |         ^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 27 previous errors