2021-05-11 19:34:14 +00:00
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use clippy_utils::diagnostics::span_lint_and_then;
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use clippy_utils::source::snippet_opt;
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use if_chain::if_chain;
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use rustc_errors::Applicability;
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use rustc_hir::{BinOpKind, Expr, ExprKind};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::ty;
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use rustc_session::{declare_lint_pass, declare_tool_lint};
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declare_clippy_lint! {
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2021-07-02 18:37:11 +00:00
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/// ### What it does
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/// Checks for uses of bitwise and/or operators between booleans, where performance may be improved by using
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/// a lazy and.
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///
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/// ### Why is this bad?
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/// The bitwise operators do not support short-circuiting, so it may hinder code performance.
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/// Additionally, boolean logic "masked" as bitwise logic is not caught by lints like `unnecessary_fold`
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///
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/// ### Known problems
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/// This lint evaluates only when the right side is determined to have no side effects. At this time, that
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/// determination is quite conservative.
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///
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/// ### Example
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/// ```rust
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/// let (x,y) = (true, false);
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/// if x & !y {} // where both x and y are booleans
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/// ```
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/// Use instead:
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/// ```rust
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/// let (x,y) = (true, false);
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/// if x && !y {}
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/// ```
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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 -.-
2021-10-21 19:06:26 +00:00
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#[clippy::version = "1.54.0"]
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pub NEEDLESS_BITWISE_BOOL,
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pedantic,
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"Boolean expressions that use bitwise rather than lazy operators"
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}
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declare_lint_pass!(NeedlessBitwiseBool => [NEEDLESS_BITWISE_BOOL]);
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fn is_bitwise_operation(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
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let ty = cx.typeck_results().expr_ty(expr);
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if_chain! {
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if !expr.span.from_expansion();
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if let (&ExprKind::Binary(ref op, _, right), &ty::Bool) = (&expr.kind, &ty.kind());
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if op.node == BinOpKind::BitAnd || op.node == BinOpKind::BitOr;
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if let ExprKind::Call(..) | ExprKind::MethodCall(..) | ExprKind::Binary(..) | ExprKind::Unary(..) = right.kind;
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if !right.can_have_side_effects();
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then {
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return true;
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}
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}
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false
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}
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2022-05-13 05:20:25 +00:00
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fn suggestion_snippet(cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<String> {
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if let ExprKind::Binary(ref op, left, right) = expr.kind {
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if let (Some(l_snippet), Some(r_snippet)) = (snippet_opt(cx, left.span), snippet_opt(cx, right.span)) {
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let op_snippet = match op.node {
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BinOpKind::BitAnd => "&&",
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_ => "||",
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};
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return Some(format!("{} {} {}", l_snippet, op_snippet, r_snippet));
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}
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}
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None
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}
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impl LateLintPass<'_> for NeedlessBitwiseBool {
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fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
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if is_bitwise_operation(cx, expr) {
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span_lint_and_then(
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cx,
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NEEDLESS_BITWISE_BOOL,
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expr.span,
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"use of bitwise operator instead of lazy operator between booleans",
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|diag| {
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if let Some(sugg) = suggestion_snippet(cx, expr) {
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diag.span_suggestion(expr.span, "try", sugg, Applicability::MachineApplicable);
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}
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},
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);
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}
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}
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}
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