use crate::utils::{
- get_trait_def_id, implements_trait, in_macro, in_macro_or_desugar, match_type, paths, snippet_opt,
+ get_trait_def_id, implements_trait, in_macro, is_type_diagnostic_item, paths, snippet_opt, span_lint_and_sugg,
span_lint_and_then, SpanlessEq,
};
use if_chain::if_chain;
-use rustc::hir::intravisit::*;
-use rustc::hir::*;
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc::{declare_lint_pass, declare_tool_lint};
+use rustc_ast::ast::LitKind;
use rustc_errors::Applicability;
-use syntax::ast::LitKind;
-use syntax::source_map::Span;
+use rustc_hir::intravisit::{walk_expr, FnKind, NestedVisitorMap, Visitor};
+use rustc_hir::{BinOpKind, Body, Expr, ExprKind, FnDecl, HirId, UnOp};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::hir::map::Map;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::source_map::Span;
declare_clippy_lint! {
/// **What it does:** Checks for boolean expressions that can be written more
fn check_fn(
&mut self,
cx: &LateContext<'a, 'tcx>,
- _: intravisit::FnKind<'tcx>,
- _: &'tcx FnDecl,
- body: &'tcx Body,
+ _: FnKind<'tcx>,
+ _: &'tcx FnDecl<'_>,
+ body: &'tcx Body<'_>,
_: Span,
_: HirId,
) {
use quine_mc_cluskey::Bool;
struct Hir2Qmm<'a, 'tcx, 'v> {
- terminals: Vec<&'v Expr>,
+ terminals: Vec<&'v Expr<'v>>,
cx: &'a LateContext<'a, 'tcx>,
}
impl<'a, 'tcx, 'v> Hir2Qmm<'a, 'tcx, 'v> {
- fn extract(&mut self, op: BinOpKind, a: &[&'v Expr], mut v: Vec<Bool>) -> Result<Vec<Bool>, String> {
+ fn extract(&mut self, op: BinOpKind, a: &[&'v Expr<'_>], mut v: Vec<Bool>) -> Result<Vec<Bool>, String> {
for a in a {
- if let ExprKind::Binary(binop, lhs, rhs) = &a.node {
+ if let ExprKind::Binary(binop, lhs, rhs) = &a.kind {
if binop.node == op {
v = self.extract(op, &[lhs, rhs], v)?;
continue;
Ok(v)
}
- fn run(&mut self, e: &'v Expr) -> Result<Bool, String> {
+ fn run(&mut self, e: &'v Expr<'_>) -> Result<Bool, String> {
fn negate(bin_op_kind: BinOpKind) -> Option<BinOpKind> {
match bin_op_kind {
BinOpKind::Eq => Some(BinOpKind::Ne),
}
// prevent folding of `cfg!` macros and the like
- if !in_macro_or_desugar(e.span) {
- match &e.node {
- ExprKind::Unary(UnNot, inner) => return Ok(Bool::Not(box self.run(inner)?)),
+ if !e.span.from_expansion() {
+ match &e.kind {
+ ExprKind::Unary(UnOp::UnNot, inner) => return Ok(Bool::Not(box self.run(inner)?)),
ExprKind::Binary(binop, lhs, rhs) => match &binop.node {
BinOpKind::Or => return Ok(Bool::Or(self.extract(BinOpKind::Or, &[lhs, rhs], Vec::new())?)),
BinOpKind::And => return Ok(Bool::And(self.extract(BinOpKind::And, &[lhs, rhs], Vec::new())?)),
}
if_chain! {
- if let ExprKind::Binary(e_binop, e_lhs, e_rhs) = &e.node;
+ if let ExprKind::Binary(e_binop, e_lhs, e_rhs) = &e.kind;
if implements_ord(self.cx, e_lhs);
- if let ExprKind::Binary(expr_binop, expr_lhs, expr_rhs) = &expr.node;
+ if let ExprKind::Binary(expr_binop, expr_lhs, expr_rhs) = &expr.kind;
if negate(e_binop.node) == Some(expr_binop.node);
if SpanlessEq::new(self.cx).ignore_fn().eq_expr(e_lhs, expr_lhs);
if SpanlessEq::new(self.cx).ignore_fn().eq_expr(e_rhs, expr_rhs);
}
struct SuggestContext<'a, 'tcx, 'v> {
- terminals: &'v [&'v Expr],
+ terminals: &'v [&'v Expr<'v>],
cx: &'a LateContext<'a, 'tcx>,
output: String,
- simplified: bool,
}
impl<'a, 'tcx, 'v> SuggestContext<'a, 'tcx, 'v> {
- fn snip(&self, e: &Expr) -> Option<String> {
- snippet_opt(self.cx, e.span)
- }
-
- fn simplify_not(&self, expr: &Expr) -> Option<String> {
- match &expr.node {
- ExprKind::Binary(binop, lhs, rhs) => {
- if !implements_ord(self.cx, lhs) {
- return None;
- }
-
- match binop.node {
- BinOpKind::Eq => Some(" != "),
- BinOpKind::Ne => Some(" == "),
- BinOpKind::Lt => Some(" >= "),
- BinOpKind::Gt => Some(" <= "),
- BinOpKind::Le => Some(" > "),
- BinOpKind::Ge => Some(" < "),
- _ => None,
- }
- .and_then(|op| Some(format!("{}{}{}", self.snip(lhs)?, op, self.snip(rhs)?)))
- },
- ExprKind::MethodCall(path, _, args) if args.len() == 1 => {
- let type_of_receiver = self.cx.tables.expr_ty(&args[0]);
- if !match_type(self.cx, type_of_receiver, &paths::OPTION)
- && !match_type(self.cx, type_of_receiver, &paths::RESULT)
- {
- return None;
- }
- METHODS_WITH_NEGATION
- .iter()
- .cloned()
- .flat_map(|(a, b)| vec![(a, b), (b, a)])
- .find(|&(a, _)| a == path.ident.name.as_str())
- .and_then(|(_, neg_method)| Some(format!("{}.{}()", self.snip(&args[0])?, neg_method)))
- },
- _ => None,
- }
- }
-
fn recurse(&mut self, suggestion: &Bool) -> Option<()> {
- use quine_mc_cluskey::Bool::*;
+ use quine_mc_cluskey::Bool::{And, False, Not, Or, Term, True};
match suggestion {
True => {
self.output.push_str("true");
},
Term(n) => {
let terminal = self.terminals[n as usize];
- if let Some(str) = self.simplify_not(terminal) {
- self.simplified = true;
+ if let Some(str) = simplify_not(self.cx, terminal) {
self.output.push_str(&str)
} else {
self.output.push('!');
- let snip = self.snip(terminal)?;
+ let snip = snippet_opt(self.cx, terminal.span)?;
self.output.push_str(&snip);
}
},
}
},
Or(v) => {
- for (index, inner) in v.iter().enumerate() {
+ for (index, inner) in v.iter().rev().enumerate() {
if index > 0 {
self.output.push_str(" || ");
}
}
},
&Term(n) => {
- let snip = self.snip(self.terminals[n as usize])?;
+ let snip = snippet_opt(self.cx, self.terminals[n as usize].span)?;
self.output.push_str(&snip);
},
}
}
}
-// The boolean part of the return indicates whether some simplifications have been applied.
-fn suggest(cx: &LateContext<'_, '_>, suggestion: &Bool, terminals: &[&Expr]) -> (String, bool) {
+fn simplify_not(cx: &LateContext<'_, '_>, expr: &Expr<'_>) -> Option<String> {
+ match &expr.kind {
+ ExprKind::Binary(binop, lhs, rhs) => {
+ if !implements_ord(cx, lhs) {
+ return None;
+ }
+
+ match binop.node {
+ BinOpKind::Eq => Some(" != "),
+ BinOpKind::Ne => Some(" == "),
+ BinOpKind::Lt => Some(" >= "),
+ BinOpKind::Gt => Some(" <= "),
+ BinOpKind::Le => Some(" > "),
+ BinOpKind::Ge => Some(" < "),
+ _ => None,
+ }
+ .and_then(|op| {
+ Some(format!(
+ "{}{}{}",
+ snippet_opt(cx, lhs.span)?,
+ op,
+ snippet_opt(cx, rhs.span)?
+ ))
+ })
+ },
+ ExprKind::MethodCall(path, _, args, _) if args.len() == 1 => {
+ let type_of_receiver = cx.tables.expr_ty(&args[0]);
+ if !is_type_diagnostic_item(cx, type_of_receiver, sym!(option_type))
+ && !is_type_diagnostic_item(cx, type_of_receiver, sym!(result_type))
+ {
+ return None;
+ }
+ METHODS_WITH_NEGATION
+ .iter()
+ .cloned()
+ .flat_map(|(a, b)| vec![(a, b), (b, a)])
+ .find(|&(a, _)| {
+ let path: &str = &path.ident.name.as_str();
+ a == path
+ })
+ .and_then(|(_, neg_method)| Some(format!("{}.{}()", snippet_opt(cx, args[0].span)?, neg_method)))
+ },
+ _ => None,
+ }
+}
+
+fn suggest(cx: &LateContext<'_, '_>, suggestion: &Bool, terminals: &[&Expr<'_>]) -> String {
let mut suggest_context = SuggestContext {
terminals,
cx,
output: String::new(),
- simplified: false,
};
suggest_context.recurse(suggestion);
- (suggest_context.output, suggest_context.simplified)
+ suggest_context.output
}
fn simple_negate(b: Bool) -> Bool {
- use quine_mc_cluskey::Bool::*;
+ use quine_mc_cluskey::Bool::{And, False, Not, Or, Term, True};
match b {
True => False,
False => True,
&Term(n) => stats.terminals[n as usize] += 1,
}
}
- use quine_mc_cluskey::Bool::*;
+ use quine_mc_cluskey::Bool::{And, False, Not, Or, Term, True};
let mut stats = Stats::default();
recurse(b, &mut stats);
stats
}
impl<'a, 'tcx> NonminimalBoolVisitor<'a, 'tcx> {
- fn bool_expr(&self, e: &Expr) {
+ fn bool_expr(&self, e: &'tcx Expr<'_>) {
let mut h2q = Hir2Qmm {
terminals: Vec::new(),
cx: self.cx,
let stats = terminal_stats(&expr);
let mut simplified = expr.simplify();
- for simple in Bool::Not(Box::new(expr.clone())).simplify() {
+ for simple in Bool::Not(Box::new(expr)).simplify() {
match simple {
Bool::Not(_) | Bool::True | Bool::False => {},
_ => simplified.push(Bool::Not(Box::new(simple.clone()))),
}
simplified.push(simple_negated);
}
- let mut improvements = Vec::new();
+ let mut improvements = Vec::with_capacity(simplified.len());
'simplified: for suggestion in &simplified {
let simplified_stats = terminal_stats(suggestion);
let mut improvement = false;
LOGIC_BUG,
e.span,
"this boolean expression contains a logic bug",
- |db| {
- db.span_help(
+ |diag| {
+ diag.span_help(
h2q.terminals[i].span,
"this expression can be optimized out by applying boolean operations to the \
outer expression",
);
- db.span_suggestion(
+ diag.span_suggestion(
e.span,
"it would look like the following",
- suggest(self.cx, suggestion, &h2q.terminals).0,
+ suggest(self.cx, suggestion, &h2q.terminals),
// nonminimal_bool can produce minimal but
// not human readable expressions (#3141)
Applicability::Unspecified,
NONMINIMAL_BOOL,
e.span,
"this boolean expression can be simplified",
- |db| {
- db.span_suggestions(
+ |diag| {
+ diag.span_suggestions(
e.span,
"try",
suggestions.into_iter(),
);
};
if improvements.is_empty() {
- let suggest = suggest(self.cx, &expr, &h2q.terminals);
- if suggest.1 {
- nonminimal_bool_lint(vec![suggest.0])
- }
+ let mut visitor = NotSimplificationVisitor { cx: self.cx };
+ visitor.visit_expr(e);
} else {
nonminimal_bool_lint(
improvements
.into_iter()
- .map(|suggestion| suggest(self.cx, suggestion, &h2q.terminals).0)
+ .map(|suggestion| suggest(self.cx, suggestion, &h2q.terminals))
.collect(),
);
}
}
impl<'a, 'tcx> Visitor<'tcx> for NonminimalBoolVisitor<'a, 'tcx> {
- fn visit_expr(&mut self, e: &'tcx Expr) {
+ type Map = Map<'tcx>;
+
+ fn visit_expr(&mut self, e: &'tcx Expr<'_>) {
if in_macro(e.span) {
return;
}
- match &e.node {
+ match &e.kind {
ExprKind::Binary(binop, _, _) if binop.node == BinOpKind::Or || binop.node == BinOpKind::And => {
self.bool_expr(e)
},
- ExprKind::Unary(UnNot, inner) => {
+ ExprKind::Unary(UnOp::UnNot, inner) => {
if self.cx.tables.node_types()[inner.hir_id].is_bool() {
self.bool_expr(e);
} else {
_ => walk_expr(self, e),
}
}
- fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
NestedVisitorMap::None
}
}
-fn implements_ord<'a, 'tcx>(cx: &'a LateContext<'a, 'tcx>, expr: &Expr) -> bool {
+fn implements_ord<'a, 'tcx>(cx: &'a LateContext<'a, 'tcx>, expr: &Expr<'_>) -> bool {
let ty = cx.tables.expr_ty(expr);
get_trait_def_id(cx, &paths::ORD).map_or(false, |id| implements_trait(cx, ty, id, &[]))
}
+
+struct NotSimplificationVisitor<'a, 'tcx> {
+ cx: &'a LateContext<'a, 'tcx>,
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for NotSimplificationVisitor<'a, 'tcx> {
+ type Map = Map<'tcx>;
+
+ fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
+ if let ExprKind::Unary(UnOp::UnNot, inner) = &expr.kind {
+ if let Some(suggestion) = simplify_not(self.cx, inner) {
+ span_lint_and_sugg(
+ self.cx,
+ NONMINIMAL_BOOL,
+ expr.span,
+ "this boolean expression can be simplified",
+ "try",
+ suggestion,
+ Applicability::MachineApplicable,
+ );
+ }
+ }
+
+ walk_expr(self, expr);
+ }
+ fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
+ NestedVisitorMap::None
+ }
+}
projects / rust.git / blobdiff