src/tools/clippy/clippy_lints/src/panic_unimplemented.rs

   1 use clippy_utils::diagnostics::span_lint;
   2 use clippy_utils::macros::{is_panic, root_macro_call_first_node};
   3 use rustc_hir::Expr;
   4 use rustc_lint::{LateContext, LateLintPass};
   5 use rustc_session::{declare_lint_pass, declare_tool_lint};
   6
   7 declare_clippy_lint! {
   8     /// ### What it does
   9     /// Checks for usage of `panic!`.
  10     ///
  11     /// ### Why is this bad?
  12     /// `panic!` will stop the execution of the executable
  13     ///
  14     /// ### Example
  15     /// ```no_run
  16     /// panic!("even with a good reason");
  17     /// ```
  18     #[clippy::version = "1.40.0"]
  19     pub PANIC,
  20     restriction,
  21     "usage of the `panic!` macro"
  22 }
  23
  24 declare_clippy_lint! {
  25     /// ### What it does
  26     /// Checks for usage of `unimplemented!`.
  27     ///
  28     /// ### Why is this bad?
  29     /// This macro should not be present in production code
  30     ///
  31     /// ### Example
  32     /// ```no_run
  33     /// unimplemented!();
  34     /// ```
  35     #[clippy::version = "pre 1.29.0"]
  36     pub UNIMPLEMENTED,
  37     restriction,
  38     "`unimplemented!` should not be present in production code"
  39 }
  40
  41 declare_clippy_lint! {
  42     /// ### What it does
  43     /// Checks for usage of `todo!`.
  44     ///
  45     /// ### Why is this bad?
  46     /// This macro should not be present in production code
  47     ///
  48     /// ### Example
  49     /// ```no_run
  50     /// todo!();
  51     /// ```
  52     #[clippy::version = "1.40.0"]
  53     pub TODO,
  54     restriction,
  55     "`todo!` should not be present in production code"
  56 }
  57
  58 declare_clippy_lint! {
  59     /// ### What it does
  60     /// Checks for usage of `unreachable!`.
  61     ///
  62     /// ### Why is this bad?
  63     /// This macro can cause code to panic
  64     ///
  65     /// ### Example
  66     /// ```no_run
  67     /// unreachable!();
  68     /// ```
  69     #[clippy::version = "1.40.0"]
  70     pub UNREACHABLE,
  71     restriction,
  72     "usage of the `unreachable!` macro"
  73 }
  74
  75 declare_lint_pass!(PanicUnimplemented => [UNIMPLEMENTED, UNREACHABLE, TODO, PANIC]);
  76
  77 impl<'tcx> LateLintPass<'tcx> for PanicUnimplemented {
  78     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
  79         let Some(macro_call) = root_macro_call_first_node(cx, expr) else { return };
  80         if is_panic(cx, macro_call.def_id) {
  81             if cx.tcx.hir().is_inside_const_context(expr.hir_id) {
  82                 return;
  83             }
  84
  85             span_lint(
  86                 cx,
  87                 PANIC,
  88                 macro_call.span,
  89                 "`panic` should not be present in production code",
  90             );
  91             return;
  92         }
  93         match cx.tcx.item_name(macro_call.def_id).as_str() {
  94             "todo" => {
  95                 span_lint(
  96                     cx,
  97                     TODO,
  98                     macro_call.span,
  99                     "`todo` should not be present in production code",
 100                 );
 101             },
 102             "unimplemented" => {
 103                 span_lint(
 104                     cx,
 105                     UNIMPLEMENTED,
 106                     macro_call.span,
 107                     "`unimplemented` should not be present in production code",
 108                 );
 109             },
 110             "unreachable" => {
 111                 span_lint(cx, UNREACHABLE, macro_call.span, "usage of the `unreachable!` macro");
 112             },
 113             _ => {},
 114         }
 115     }
 116 }