mirror of
https://github.com/rust-lang/rust-clippy
synced 2024-12-22 02:53:20 +00:00
57 lines
2.1 KiB
Rust
57 lines
2.1 KiB
Rust
use rustc::hir::*;
|
|
use rustc::lint::*;
|
|
use syntax::ast::LitKind;
|
|
use utils::{is_direct_expn_of, match_def_path, opt_def_id, paths, resolve_node, span_lint};
|
|
|
|
/// **What it does:** Checks for missing parameters in `panic!`.
|
|
///
|
|
/// **Why is this bad?** Contrary to the `format!` family of macros, there are
|
|
/// two forms of `panic!`: if there are no parameters given, the first argument
|
|
/// is not a format string and used literally. So while `format!("{}")` will
|
|
/// fail to compile, `panic!("{}")` will not.
|
|
///
|
|
/// **Known problems:** Should you want to use curly brackets in `panic!`
|
|
/// without any parameter, this lint will warn.
|
|
///
|
|
/// **Example:**
|
|
/// ```rust
|
|
/// panic!("This `panic!` is probably missing a parameter there: {}");
|
|
/// ```
|
|
declare_lint! {
|
|
pub PANIC_PARAMS,
|
|
Warn,
|
|
"missing parameters in `panic!` calls"
|
|
}
|
|
|
|
#[allow(missing_copy_implementations)]
|
|
pub struct Pass;
|
|
|
|
impl LintPass for Pass {
|
|
fn get_lints(&self) -> LintArray {
|
|
lint_array!(PANIC_PARAMS)
|
|
}
|
|
}
|
|
|
|
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
|
|
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
|
|
if_chain! {
|
|
if let ExprBlock(ref block) = expr.node;
|
|
if let Some(ref ex) = block.expr;
|
|
if let ExprCall(ref fun, ref params) = ex.node;
|
|
if params.len() == 2;
|
|
if let ExprPath(ref qpath) = fun.node;
|
|
if let Some(fun_def_id) = opt_def_id(resolve_node(cx, qpath, fun.hir_id));
|
|
if match_def_path(cx.tcx, fun_def_id, &paths::BEGIN_PANIC);
|
|
if let ExprLit(ref lit) = params[0].node;
|
|
if is_direct_expn_of(expr.span, "panic").is_some();
|
|
if let LitKind::Str(ref string, _) = lit.node;
|
|
if let Some(par) = string.as_str().find('{');
|
|
if string.as_str()[par..].contains('}');
|
|
if params[0].span.source_callee().is_none();
|
|
then {
|
|
span_lint(cx, PANIC_PARAMS, params[0].span,
|
|
"you probably are missing some parameter in your format string");
|
|
}
|
|
}
|
|
}
|
|
}
|