1 // Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution.
4 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
5 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
7 // option. This file may not be copied, modified, or distributed
8 // except according to those terms.
11 use crate::rustc::hir::*;
12 use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
13 use crate::rustc::{declare_tool_lint, lint_array};
14 use if_chain::if_chain;
15 use crate::syntax::ast::LitKind;
16 use crate::syntax::ptr::P;
17 use crate::syntax::ext::quote::rt::Span;
18 use crate::utils::{is_direct_expn_of, is_expn_of, match_def_path, opt_def_id, paths, resolve_node, span_lint};
20 /// **What it does:** Checks for missing parameters in `panic!`.
22 /// **Why is this bad?** Contrary to the `format!` family of macros, there are
23 /// two forms of `panic!`: if there are no parameters given, the first argument
24 /// is not a format string and used literally. So while `format!("{}")` will
25 /// fail to compile, `panic!("{}")` will not.
27 /// **Known problems:** None.
31 /// panic!("This `panic!` is probably missing a parameter there: {}");
33 declare_clippy_lint! {
36 "missing parameters in `panic!` calls"
39 /// **What it does:** Checks for usage of `unimplemented!`.
41 /// **Why is this bad?** This macro should not be present in production code
43 /// **Known problems:** None.
49 declare_clippy_lint! {
52 "`unimplemented!` should not be present in production code"
57 impl LintPass for Pass {
58 fn get_lints(&self) -> LintArray {
59 lint_array!(PANIC_PARAMS, UNIMPLEMENTED)
63 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
64 fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
66 if let ExprKind::Block(ref block, _) = expr.node;
67 if let Some(ref ex) = block.expr;
68 if let ExprKind::Call(ref fun, ref params) = ex.node;
69 if let ExprKind::Path(ref qpath) = fun.node;
70 if let Some(fun_def_id) = opt_def_id(resolve_node(cx, qpath, fun.hir_id));
71 if match_def_path(cx.tcx, fun_def_id, &paths::BEGIN_PANIC);
74 if is_expn_of(expr.span, "unimplemented").is_some() {
75 let span = get_outer_span(expr);
76 span_lint(cx, UNIMPLEMENTED, span,
77 "`unimplemented` should not be present in production code");
79 match_panic(params, expr, cx);
86 fn get_outer_span(expr: &Expr) -> Span {
88 if let Some(first) = expr.span.ctxt().outer().expn_info();
89 if let Some(second) = first.call_site.ctxt().outer().expn_info();
98 fn match_panic(params: &P<[Expr]>, expr: &Expr, cx: &LateContext<'_, '_>) {
100 if let ExprKind::Lit(ref lit) = params[0].node;
101 if is_direct_expn_of(expr.span, "panic").is_some();
102 if let LitKind::Str(ref string, _) = lit.node;
103 let string = string.as_str().replace("{{", "").replace("}}", "");
104 if let Some(par) = string.find('{');
105 if string[par..].contains('}');
106 if params[0].span.source_callee().is_none();
107 if params[0].span.lo() != params[0].span.hi();
109 span_lint(cx, PANIC_PARAMS, params[0].span,
110 "you probably are missing some parameter in your format string");