rust-clippy/clippy_lints/src/verbose_file_reads.rs
xFrednet d647696c1f
Added clippy::version attribute to all normal lints
So, some context for this, well, more a story. I'm not used to scripting, I've never really scripted anything, even if it's a valuable skill. I just never really needed it. Now, `@flip1995` correctly suggested using a script for this in `rust-clippy#7813`...

And I decided to write a script using nushell because why not? This was a mistake... I spend way more time on this than I would like to admit. It has definitely been more than 4 hours. It shouldn't take that long, but me being new to scripting and nushell just wasn't a good mixture... Anyway, here is the script that creates another script which adds the versions. Fun...

Just execute this on the `gh-pages` branch and the resulting `replacer.sh` in `clippy_lints` and it should all work.

```nu
mv v0.0.212 rust-1.00.0;
mv beta rust-1.57.0;
mv master rust-1.58.0;

let paths = (open ./rust-1.58.0/lints.json | select id id_span | flatten | select id path);
let versions = (
    ls | where name =~ "rust-" | select name | format {name}/lints.json |
    each { open $it | select id | insert version $it | str substring "5,11" version} |
    group-by id | rotate counter-clockwise id version |
    update version {get version | first 1} | flatten | select id version);
$paths | each { |row|
    let version = ($versions | where id == ($row.id) | format {version})
    let idu = ($row.id | str upcase)
    $"sed -i '0,/($idu),/{s/pub ($idu),/#[clippy::version = "($version)"]\n    pub ($idu),/}' ($row.path)"
} | str collect ";" | str find-replace --all '1.00.0' 'pre 1.29.0' | save "replacer.sh";
```

And this still has some problems, but at this point I just want to be done -.-
2021-11-10 19:48:31 +01:00

88 lines
3 KiB
Rust

use clippy_utils::diagnostics::span_lint_and_help;
use clippy_utils::paths;
use clippy_utils::ty::match_type;
use if_chain::if_chain;
use rustc_hir::{Expr, ExprKind, QPath};
use rustc_lint::{LateContext, LateLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
declare_clippy_lint! {
/// ### What it does
/// Checks for use of File::read_to_end and File::read_to_string.
///
/// ### Why is this bad?
/// `fs::{read, read_to_string}` provide the same functionality when `buf` is empty with fewer imports and no intermediate values.
/// See also: [fs::read docs](https://doc.rust-lang.org/std/fs/fn.read.html), [fs::read_to_string docs](https://doc.rust-lang.org/std/fs/fn.read_to_string.html)
///
/// ### Example
/// ```rust,no_run
/// # use std::io::Read;
/// # use std::fs::File;
/// let mut f = File::open("foo.txt").unwrap();
/// let mut bytes = Vec::new();
/// f.read_to_end(&mut bytes).unwrap();
/// ```
/// Can be written more concisely as
/// ```rust,no_run
/// # use std::fs;
/// let mut bytes = fs::read("foo.txt").unwrap();
/// ```
#[clippy::version = "1.44.0"]
pub VERBOSE_FILE_READS,
restriction,
"use of `File::read_to_end` or `File::read_to_string`"
}
declare_lint_pass!(VerboseFileReads => [VERBOSE_FILE_READS]);
impl<'tcx> LateLintPass<'tcx> for VerboseFileReads {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
if is_file_read_to_end(cx, expr) {
span_lint_and_help(
cx,
VERBOSE_FILE_READS,
expr.span,
"use of `File::read_to_end`",
None,
"consider using `fs::read` instead",
);
} else if is_file_read_to_string(cx, expr) {
span_lint_and_help(
cx,
VERBOSE_FILE_READS,
expr.span,
"use of `File::read_to_string`",
None,
"consider using `fs::read_to_string` instead",
);
}
}
}
fn is_file_read_to_end<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool {
if_chain! {
if let ExprKind::MethodCall(method_name, _, exprs, _) = expr.kind;
if method_name.ident.as_str() == "read_to_end";
if let ExprKind::Path(QPath::Resolved(None, _)) = &exprs[0].kind;
let ty = cx.typeck_results().expr_ty(&exprs[0]);
if match_type(cx, ty, &paths::FILE);
then {
return true
}
}
false
}
fn is_file_read_to_string<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool {
if_chain! {
if let ExprKind::MethodCall(method_name, _, exprs, _) = expr.kind;
if method_name.ident.as_str() == "read_to_string";
if let ExprKind::Path(QPath::Resolved(None, _)) = &exprs[0].kind;
let ty = cx.typeck_results().expr_ty(&exprs[0]);
if match_type(cx, ty, &paths::FILE);
then {
return true
}
}
false
}