Enable clippy::panic in const contexts (#15565)

Fixes rust-lang/rust-clippy#15564.

changelog: [`cargo::panic`]: Enabled to run in `const` contexts

Author: samueltardieu

clippy_lints/src/panic_unimplemented.rs

@@ -1,7 +1,7 @@
 use clippy_config::Conf;
 use clippy_utils::diagnostics::span_lint;
-use clippy_utils::is_in_test;
 use clippy_utils::macros::{is_panic, root_macro_call_first_node};
+use clippy_utils::{is_in_test, is_inside_always_const_context};
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::{Expr, ExprKind, QPath};
 use rustc_lint::{LateContext, LateLintPass};
@@ -99,7 +99,7 @@ impl<'tcx> LateLintPass<'tcx> for PanicUnimplemented {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if let Some(macro_call) = root_macro_call_first_node(cx, expr) {
             if is_panic(cx, macro_call.def_id) {
-                if cx.tcx.hir_is_inside_const_context(expr.hir_id)
+                if is_inside_always_const_context(cx.tcx, expr.hir_id)
                     || self.allow_panic_in_tests && is_in_test(cx.tcx, expr.hir_id)
                 {
                     return;
@@ -140,7 +140,7 @@ impl<'tcx> LateLintPass<'tcx> for PanicUnimplemented {
             && let Res::Def(DefKind::Fn, def_id) = expr_path.res
             && cx.tcx.is_diagnostic_item(sym::panic_any, def_id)
         {
-            if cx.tcx.hir_is_inside_const_context(expr.hir_id)
+            if is_inside_always_const_context(cx.tcx, expr.hir_id)
                 || self.allow_panic_in_tests && is_in_test(cx.tcx, expr.hir_id)
             {
                 return;

tests/ui/panicking_macros.rs

@@ -31,6 +31,20 @@ fn panic() {
     let b = a + 2;
 }
 
+const fn panic_const() {
+    let a = 2;
+    panic!();
+    //~^ panic
+
+    panic!("message");
+    //~^ panic
+
+    panic!("{} {}", "panic with", "multiple arguments");
+    //~^ panic
+
+    let b = a + 2;
+}
+
 fn todo() {
     let a = 2;
     todo!();
@@ -114,6 +128,7 @@ fn debug_assert_msg() {
 
 fn main() {
     panic();
+    panic_const();
     todo();
     unimplemented();
     unreachable();

tests/ui/panicking_macros.stderr

@@ -19,29 +19,47 @@ error: `panic` should not be present in production code
 LL |     panic!("{} {}", "panic with", "multiple arguments");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: `todo` should not be present in production code
+error: `panic` should not be present in production code
   --> tests/ui/panicking_macros.rs:36:5
    |
+LL |     panic!();
+   |     ^^^^^^^^
+
+error: `panic` should not be present in production code
+  --> tests/ui/panicking_macros.rs:39:5
+   |
+LL |     panic!("message");
+   |     ^^^^^^^^^^^^^^^^^
+
+error: `panic` should not be present in production code
+  --> tests/ui/panicking_macros.rs:42:5
+   |
+LL |     panic!("{} {}", "panic with", "multiple arguments");
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: `todo` should not be present in production code
+  --> tests/ui/panicking_macros.rs:50:5
+   |
 LL |     todo!();
    |     ^^^^^^^
    |
    = note: `-D clippy::todo` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(clippy::todo)]`
 
 error: `todo` should not be present in production code
-  --> tests/ui/panicking_macros.rs:39:5
+  --> tests/ui/panicking_macros.rs:53:5
    |
 LL |     todo!("message");
    |     ^^^^^^^^^^^^^^^^
 
 error: `todo` should not be present in production code
-  --> tests/ui/panicking_macros.rs:42:5
+  --> tests/ui/panicking_macros.rs:56:5
    |
 LL |     todo!("{} {}", "panic with", "multiple arguments");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `unimplemented` should not be present in production code
-  --> tests/ui/panicking_macros.rs:50:5
+  --> tests/ui/panicking_macros.rs:64:5
    |
 LL |     unimplemented!();
    |     ^^^^^^^^^^^^^^^^
@@ -50,19 +68,19 @@ LL |     unimplemented!();
    = help: to override `-D warnings` add `#[allow(clippy::unimplemented)]`
 
 error: `unimplemented` should not be present in production code
-  --> tests/ui/panicking_macros.rs:53:5
+  --> tests/ui/panicking_macros.rs:67:5
    |
 LL |     unimplemented!("message");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `unimplemented` should not be present in production code
-  --> tests/ui/panicking_macros.rs:56:5
+  --> tests/ui/panicking_macros.rs:70:5
    |
 LL |     unimplemented!("{} {}", "panic with", "multiple arguments");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: usage of the `unreachable!` macro
-  --> tests/ui/panicking_macros.rs:64:5
+  --> tests/ui/panicking_macros.rs:78:5
    |
 LL |     unreachable!();
    |     ^^^^^^^^^^^^^^
@@ -71,40 +89,40 @@ LL |     unreachable!();
    = help: to override `-D warnings` add `#[allow(clippy::unreachable)]`
 
 error: usage of the `unreachable!` macro
-  --> tests/ui/panicking_macros.rs:67:5
+  --> tests/ui/panicking_macros.rs:81:5
    |
 LL |     unreachable!("message");
    |     ^^^^^^^^^^^^^^^^^^^^^^^
 
 error: usage of the `unreachable!` macro
-  --> tests/ui/panicking_macros.rs:70:5
+  --> tests/ui/panicking_macros.rs:84:5
    |
 LL |     unreachable!("{} {}", "panic with", "multiple arguments");
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `panic` should not be present in production code
-  --> tests/ui/panicking_macros.rs:78:5
+  --> tests/ui/panicking_macros.rs:92:5
    |
 LL |     panic!();
    |     ^^^^^^^^
 
 error: `todo` should not be present in production code
-  --> tests/ui/panicking_macros.rs:81:5
+  --> tests/ui/panicking_macros.rs:95:5
    |
 LL |     todo!();
    |     ^^^^^^^
 
 error: `unimplemented` should not be present in production code
-  --> tests/ui/panicking_macros.rs:84:5
+  --> tests/ui/panicking_macros.rs:98:5
    |
 LL |     unimplemented!();
    |     ^^^^^^^^^^^^^^^^
 
 error: usage of the `unreachable!` macro
-  --> tests/ui/panicking_macros.rs:87:5
+  --> tests/ui/panicking_macros.rs:101:5
    |
 LL |     unreachable!();
    |     ^^^^^^^^^^^^^^
 
-error: aborting due to 16 previous errors
+error: aborting due to 19 previous errors