OpenE2K
/
rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Don’t use `{:?}` and use span_suggestion in TOPLEVEL_REF_ARG

This commit is contained in:
mcarton 2016-02-07 18:28:37 +01:00
parent d27aa960b6
commit 1a8b8cd28f
2 changed files with 19 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
src/misc.rs
View File

@ -11,7 +11,7 @@ use rustc::middle::const_eval::eval_const_expr_partial;
use rustc::middle::const_eval::EvalHint::ExprTypeChecked;
use utils::{get_item_name, match_path, snippet, get_parent_expr, span_lint};
use utils::{span_help_and_lint, walk_ptrs_ty, is_integer_literal, implements_trait};
use utils::{span_lint_and_then, walk_ptrs_ty, is_integer_literal, implements_trait};
/// **What it does:** This lint checks for function arguments and let bindings denoted as `ref`.
///
@ -62,16 +62,22 @@ impl LateLintPass for TopLevelRefPass {
let Some(ref init) = l.init
], {
let tyopt = if let Some(ref ty) = l.ty {
format!(": {:?} ", ty)
format!(": {}", snippet(cx, ty.span, "_"))
} else {
"".to_owned()
};
span_help_and_lint(cx,
span_lint_and_then(cx,
TOPLEVEL_REF_ARG,
l.pat.span,
"`ref` on an entire `let` pattern is discouraged, take a reference with & instead",
&format!("try `let {} {}= &{};`", snippet(cx, i.span, "_"),
tyopt, snippet(cx, init.span, "_"))
|db| {
db.span_suggestion(s.span,
"try",
format!("let {}{} = &{};",
snippet(cx, i.span, "_"),
tyopt,
snippet(cx, init.span, "_")));
}
);
}
};

12
tests/compile-fail/toplevel_ref_arg.rs
View File

@ -15,11 +15,15 @@ fn main() {
let y = |ref x| { println!("{:?}", x) };
y(1u8);
let ref x = 1; //~ ERROR `ref` on an entire `let` pattern is discouraged
//~^ HELP try `let x = &1;`
let ref x = 1;
//~^ ERROR `ref` on an entire `let` pattern is discouraged
//~| HELP try
//~| SUGGESTION let x = &1;
let ref y = (&1, 2); //~ ERROR `ref` on an entire `let` pattern is discouraged
//~^ HELP try `let y = &(&1, 2);`
let ref y : (&_, u8) = (&1, 2);
//~^ ERROR `ref` on an entire `let` pattern is discouraged
//~| HELP try
//~| SUGGESTION let y: (&_, u8) = &(&1, 2);
let (ref x, _) = (1,2); // okay, not top level
println!("The answer is {}.", x);