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Factor out clippy_utils crate

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This commit is contained in:
Samuel E. Moelius III 2021-02-17 12:42:21 -05:00
parent a2c25fa9f0
commit 09bded4437
30 changed files with 778 additions and 681 deletions
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1
.gitignore vendored
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@ -18,6 +18,7 @@ out
*Cargo.lock
/target
/clippy_lints/target
/clippy_utils/target
/clippy_workspace_tests/target
/clippy_dev/target
/rustc_tools_util/target

1
clippy_lints/Cargo.toml
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@ -18,6 +18,7 @@ edition = "2018"
[dependencies]
cargo_metadata = "0.12"
clippy_utils = { path = "../clippy_utils" }
if_chain = "1.0.0"
itertools = "0.9"
pulldown-cmark = { version = "0.8", default-features = false }

575
clippy_lints/src/consts.rs
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@ -1,574 +1 @@
#![allow(clippy::float_cmp)]
use crate::utils::{clip, sext, unsext};
use if_chain::if_chain;
use rustc_ast::ast::{self, LitFloatType, LitKind};
use rustc_data_structures::sync::Lrc;
use rustc_hir::def::{DefKind, Res};
use rustc_hir::{BinOp, BinOpKind, Block, Expr, ExprKind, HirId, QPath, UnOp};
use rustc_lint::LateContext;
use rustc_middle::mir::interpret::Scalar;
use rustc_middle::ty::subst::{Subst, SubstsRef};
use rustc_middle::ty::{self, FloatTy, ScalarInt, Ty, TyCtxt};
use rustc_middle::{bug, span_bug};
use rustc_span::symbol::Symbol;
use std::cmp::Ordering::{self, Equal};
use std::convert::TryInto;
use std::hash::{Hash, Hasher};
/// A `LitKind`-like enum to fold constant `Expr`s into.
#[derive(Debug, Clone)]
pub enum Constant {
/// A `String` (e.g., "abc").
Str(String),
/// A binary string (e.g., `b"abc"`).
Binary(Lrc<[u8]>),
/// A single `char` (e.g., `'a'`).
Char(char),
/// An integer's bit representation.
Int(u128),
/// An `f32`.
F32(f32),
/// An `f64`.
F64(f64),
/// `true` or `false`.
Bool(bool),
/// An array of constants.
Vec(Vec<Constant>),
/// Also an array, but with only one constant, repeated N times.
Repeat(Box<Constant>, u64),
/// A tuple of constants.
Tuple(Vec<Constant>),
/// A raw pointer.
RawPtr(u128),
/// A reference
Ref(Box<Constant>),
/// A literal with syntax error.
Err(Symbol),
}
impl PartialEq for Constant {
fn eq(&self, other: &Self) -> bool {
match (self, other) {
(&Self::Str(ref ls), &Self::Str(ref rs)) => ls == rs,
(&Self::Binary(ref l), &Self::Binary(ref r)) => l == r,
(&Self::Char(l), &Self::Char(r)) => l == r,
(&Self::Int(l), &Self::Int(r)) => l == r,
(&Self::F64(l), &Self::F64(r)) => {
// We want `Fw32 == FwAny` and `FwAny == Fw64`, and by transitivity we must have
// `Fw32 == Fw64`, so don’t compare them.
// `to_bits` is required to catch non-matching 0.0, -0.0, and NaNs.
l.to_bits() == r.to_bits()
},
(&Self::F32(l), &Self::F32(r)) => {
// We want `Fw32 == FwAny` and `FwAny == Fw64`, and by transitivity we must have
// `Fw32 == Fw64`, so don’t compare them.
// `to_bits` is required to catch non-matching 0.0, -0.0, and NaNs.
f64::from(l).to_bits() == f64::from(r).to_bits()
},
(&Self::Bool(l), &Self::Bool(r)) => l == r,
(&Self::Vec(ref l), &Self::Vec(ref r)) | (&Self::Tuple(ref l), &Self::Tuple(ref r)) => l == r,
(&Self::Repeat(ref lv, ref ls), &Self::Repeat(ref rv, ref rs)) => ls == rs && lv == rv,
(&Self::Ref(ref lb), &Self::Ref(ref rb)) => *lb == *rb,
// TODO: are there inter-type equalities?
_ => false,
}
}
}
impl Hash for Constant {
fn hash<H>(&self, state: &mut H)
where
H: Hasher,
{
std::mem::discriminant(self).hash(state);
match *self {
Self::Str(ref s) => {
s.hash(state);
},
Self::Binary(ref b) => {
b.hash(state);
},
Self::Char(c) => {
c.hash(state);
},
Self::Int(i) => {
i.hash(state);
},
Self::F32(f) => {
f64::from(f).to_bits().hash(state);
},
Self::F64(f) => {
f.to_bits().hash(state);
},
Self::Bool(b) => {
b.hash(state);
},
Self::Vec(ref v) | Self::Tuple(ref v) => {
v.hash(state);
},
Self::Repeat(ref c, l) => {
c.hash(state);
l.hash(state);
},
Self::RawPtr(u) => {
u.hash(state);
},
Self::Ref(ref r) => {
r.hash(state);
},
Self::Err(ref s) => {
s.hash(state);
},
}
}
}
impl Constant {
pub fn partial_cmp(tcx: TyCtxt<'_>, cmp_type: Ty<'_>, left: &Self, right: &Self) -> Option<Ordering> {
match (left, right) {
(&Self::Str(ref ls), &Self::Str(ref rs)) => Some(ls.cmp(rs)),
(&Self::Char(ref l), &Self::Char(ref r)) => Some(l.cmp(r)),
(&Self::Int(l), &Self::Int(r)) => {
if let ty::Int(int_ty) = *cmp_type.kind() {
Some(sext(tcx, l, int_ty).cmp(&sext(tcx, r, int_ty)))
} else {
Some(l.cmp(&r))
}
},
(&Self::F64(l), &Self::F64(r)) => l.partial_cmp(&r),
(&Self::F32(l), &Self::F32(r)) => l.partial_cmp(&r),
(&Self::Bool(ref l), &Self::Bool(ref r)) => Some(l.cmp(r)),
(&Self::Tuple(ref l), &Self::Tuple(ref r)) | (&Self::Vec(ref l), &Self::Vec(ref r)) => l
.iter()
.zip(r.iter())
.map(|(li, ri)| Self::partial_cmp(tcx, cmp_type, li, ri))
.find(|r| r.map_or(true, |o| o != Ordering::Equal))
.unwrap_or_else(|| Some(l.len().cmp(&r.len()))),
(&Self::Repeat(ref lv, ref ls), &Self::Repeat(ref rv, ref rs)) => {
match Self::partial_cmp(tcx, cmp_type, lv, rv) {
Some(Equal) => Some(ls.cmp(rs)),
x => x,
}
},
(&Self::Ref(ref lb), &Self::Ref(ref rb)) => Self::partial_cmp(tcx, cmp_type, lb, rb),
// TODO: are there any useful inter-type orderings?
_ => None,
}
}
}
/// Parses a `LitKind` to a `Constant`.
pub fn lit_to_constant(lit: &LitKind, ty: Option<Ty<'_>>) -> Constant {
match *lit {
LitKind::Str(ref is, _) => Constant::Str(is.to_string()),
LitKind::Byte(b) => Constant::Int(u128::from(b)),
LitKind::ByteStr(ref s) => Constant::Binary(Lrc::clone(s)),
LitKind::Char(c) => Constant::Char(c),
LitKind::Int(n, _) => Constant::Int(n),
LitKind::Float(ref is, LitFloatType::Suffixed(fty)) => match fty {
ast::FloatTy::F32 => Constant::F32(is.as_str().parse().unwrap()),
ast::FloatTy::F64 => Constant::F64(is.as_str().parse().unwrap()),
},
LitKind::Float(ref is, LitFloatType::Unsuffixed) => match ty.expect("type of float is known").kind() {
ty::Float(FloatTy::F32) => Constant::F32(is.as_str().parse().unwrap()),
ty::Float(FloatTy::F64) => Constant::F64(is.as_str().parse().unwrap()),
_ => bug!(),
},
LitKind::Bool(b) => Constant::Bool(b),
LitKind::Err(s) => Constant::Err(s),
}
}
pub fn constant<'tcx>(
lcx: &LateContext<'tcx>,
typeck_results: &ty::TypeckResults<'tcx>,
e: &Expr<'_>,
) -> Option<(Constant, bool)> {
let mut cx = ConstEvalLateContext {
lcx,
typeck_results,
param_env: lcx.param_env,
needed_resolution: false,
substs: lcx.tcx.intern_substs(&[]),
};
cx.expr(e).map(|cst| (cst, cx.needed_resolution))
}
pub fn constant_simple<'tcx>(
lcx: &LateContext<'tcx>,
typeck_results: &ty::TypeckResults<'tcx>,
e: &Expr<'_>,
) -> Option<Constant> {
constant(lcx, typeck_results, e).and_then(|(cst, res)| if res { None } else { Some(cst) })
}
/// Creates a `ConstEvalLateContext` from the given `LateContext` and `TypeckResults`.
pub fn constant_context<'a, 'tcx>(
lcx: &'a LateContext<'tcx>,
typeck_results: &'a ty::TypeckResults<'tcx>,
) -> ConstEvalLateContext<'a, 'tcx> {
ConstEvalLateContext {
lcx,
typeck_results,
param_env: lcx.param_env,
needed_resolution: false,
substs: lcx.tcx.intern_substs(&[]),
}
}
pub struct ConstEvalLateContext<'a, 'tcx> {
lcx: &'a LateContext<'tcx>,
typeck_results: &'a ty::TypeckResults<'tcx>,
param_env: ty::ParamEnv<'tcx>,
needed_resolution: bool,
substs: SubstsRef<'tcx>,
}
impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
/// Simple constant folding: Insert an expression, get a constant or none.
pub fn expr(&mut self, e: &Expr<'_>) -> Option<Constant> {
match e.kind {
ExprKind::Path(ref qpath) => self.fetch_path(qpath, e.hir_id, self.typeck_results.expr_ty(e)),
ExprKind::Block(ref block, _) => self.block(block),
ExprKind::Lit(ref lit) => Some(lit_to_constant(&lit.node, self.typeck_results.expr_ty_opt(e))),
ExprKind::Array(ref vec) => self.multi(vec).map(Constant::Vec),
ExprKind::Tup(ref tup) => self.multi(tup).map(Constant::Tuple),
ExprKind::Repeat(ref value, _) => {
let n = match self.typeck_results.expr_ty(e).kind() {
ty::Array(_, n) => n.try_eval_usize(self.lcx.tcx, self.lcx.param_env)?,
_ => span_bug!(e.span, "typeck error"),
};
self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))
},
ExprKind::Unary(op, ref operand) => self.expr(operand).and_then(|o| match op {
UnOp::Not => self.constant_not(&o, self.typeck_results.expr_ty(e)),
UnOp::Neg => self.constant_negate(&o, self.typeck_results.expr_ty(e)),
UnOp::Deref => Some(if let Constant::Ref(r) = o { *r } else { o }),
}),
ExprKind::If(ref cond, ref then, ref otherwise) => self.ifthenelse(cond, then, *otherwise),
ExprKind::Binary(op, ref left, ref right) => self.binop(op, left, right),
ExprKind::Call(ref callee, ref args) => {
// We only handle a few const functions for now.
if_chain! {
if args.is_empty();
if let ExprKind::Path(qpath) = &callee.kind;
let res = self.typeck_results.qpath_res(qpath, callee.hir_id);
if let Some(def_id) = res.opt_def_id();
let def_path: Vec<_> = self.lcx.get_def_path(def_id).into_iter().map(Symbol::as_str).collect();
let def_path: Vec<&str> = def_path.iter().take(4).map(|s| &**s).collect();
if let ["core", "num", int_impl, "max_value"] = *def_path;
then {
let value = match int_impl {
"<impl i8>" => i8::MAX as u128,
"<impl i16>" => i16::MAX as u128,
"<impl i32>" => i32::MAX as u128,
"<impl i64>" => i64::MAX as u128,
"<impl i128>" => i128::MAX as u128,
_ => return None,
};
Some(Constant::Int(value))
}
else {
None
}
}
},
ExprKind::Index(ref arr, ref index) => self.index(arr, index),
ExprKind::AddrOf(_, _, ref inner) => self.expr(inner).map(|r| Constant::Ref(Box::new(r))),
// TODO: add other expressions.
_ => None,
}
}
#[allow(clippy::cast_possible_wrap)]
fn constant_not(&self, o: &Constant, ty: Ty<'_>) -> Option<Constant> {
use self::Constant::{Bool, Int};
match *o {
Bool(b) => Some(Bool(!b)),
Int(value) => {
let value = !value;
match *ty.kind() {
ty::Int(ity) => Some(Int(unsext(self.lcx.tcx, value as i128, ity))),
ty::Uint(ity) => Some(Int(clip(self.lcx.tcx, value, ity))),
_ => None,
}
},
_ => None,
}
}
fn constant_negate(&self, o: &Constant, ty: Ty<'_>) -> Option<Constant> {
use self::Constant::{Int, F32, F64};
match *o {
Int(value) => {
let ity = match *ty.kind() {
ty::Int(ity) => ity,
_ => return None,
};
// sign extend
let value = sext(self.lcx.tcx, value, ity);
let value = value.checked_neg()?;
// clear unused bits
Some(Int(unsext(self.lcx.tcx, value, ity)))
},
F32(f) => Some(F32(-f)),
F64(f) => Some(F64(-f)),
_ => None,
}
}
/// Create `Some(Vec![..])` of all constants, unless there is any
/// non-constant part.
fn multi(&mut self, vec: &[Expr<'_>]) -> Option<Vec<Constant>> {
vec.iter().map(|elem| self.expr(elem)).collect::<Option<_>>()
}
/// Lookup a possibly constant expression from a `ExprKind::Path`.
fn fetch_path(&mut self, qpath: &QPath<'_>, id: HirId, ty: Ty<'tcx>) -> Option<Constant> {
let res = self.typeck_results.qpath_res(qpath, id);
match res {
Res::Def(DefKind::Const | DefKind::AssocConst, def_id) => {
let substs = self.typeck_results.node_substs(id);
let substs = if self.substs.is_empty() {
substs
} else {
substs.subst(self.lcx.tcx, self.substs)
};
let result = self
.lcx
.tcx
.const_eval_resolve(
self.param_env,
ty::WithOptConstParam::unknown(def_id),
substs,
None,
None,
)
.ok()
.map(|val| rustc_middle::ty::Const::from_value(self.lcx.tcx, val, ty))?;
let result = miri_to_const(&result);
if result.is_some() {
self.needed_resolution = true;
}
result
},
// FIXME: cover all usable cases.
_ => None,
}
}
fn index(&mut self, lhs: &'_ Expr<'_>, index: &'_ Expr<'_>) -> Option<Constant> {
let lhs = self.expr(lhs);
let index = self.expr(index);
match (lhs, index) {
(Some(Constant::Vec(vec)), Some(Constant::Int(index))) => match vec.get(index as usize) {
Some(Constant::F32(x)) => Some(Constant::F32(*x)),
Some(Constant::F64(x)) => Some(Constant::F64(*x)),
_ => None,
},
(Some(Constant::Vec(vec)), _) => {
if !vec.is_empty() && vec.iter().all(|x| *x == vec[0]) {
match vec.get(0) {
Some(Constant::F32(x)) => Some(Constant::F32(*x)),
Some(Constant::F64(x)) => Some(Constant::F64(*x)),
_ => None,
}
} else {
None
}
},
_ => None,
}
}
/// A block can only yield a constant if it only has one constant expression.
fn block(&mut self, block: &Block<'_>) -> Option<Constant> {
if block.stmts.is_empty() {
block.expr.as_ref().and_then(|b| self.expr(b))
} else {
None
}
}
fn ifthenelse(&mut self, cond: &Expr<'_>, then: &Expr<'_>, otherwise: Option<&Expr<'_>>) -> Option<Constant> {
if let Some(Constant::Bool(b)) = self.expr(cond) {
if b {
self.expr(&*then)
} else {
otherwise.as_ref().and_then(|expr| self.expr(expr))
}
} else {
None
}
}
fn binop(&mut self, op: BinOp, left: &Expr<'_>, right: &Expr<'_>) -> Option<Constant> {
let l = self.expr(left)?;
let r = self.expr(right);
match (l, r) {
(Constant::Int(l), Some(Constant::Int(r))) => match *self.typeck_results.expr_ty_opt(left)?.kind() {
ty::Int(ity) => {
let l = sext(self.lcx.tcx, l, ity);
let r = sext(self.lcx.tcx, r, ity);
let zext = |n: i128| Constant::Int(unsext(self.lcx.tcx, n, ity));
match op.node {
BinOpKind::Add => l.checked_add(r).map(zext),
BinOpKind::Sub => l.checked_sub(r).map(zext),
BinOpKind::Mul => l.checked_mul(r).map(zext),
BinOpKind::Div if r != 0 => l.checked_div(r).map(zext),
BinOpKind::Rem if r != 0 => l.checked_rem(r).map(zext),
BinOpKind::Shr => l.checked_shr(r.try_into().expect("invalid shift")).map(zext),
BinOpKind::Shl => l.checked_shl(r.try_into().expect("invalid shift")).map(zext),
BinOpKind::BitXor => Some(zext(l ^ r)),
BinOpKind::BitOr => Some(zext(l | r)),
BinOpKind::BitAnd => Some(zext(l & r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
}
},
ty::Uint(_) => match op.node {
BinOpKind::Add => l.checked_add(r).map(Constant::Int),
BinOpKind::Sub => l.checked_sub(r).map(Constant::Int),
BinOpKind::Mul => l.checked_mul(r).map(Constant::Int),
BinOpKind::Div => l.checked_div(r).map(Constant::Int),
BinOpKind::Rem => l.checked_rem(r).map(Constant::Int),
BinOpKind::Shr => l.checked_shr(r.try_into().expect("shift too large")).map(Constant::Int),
BinOpKind::Shl => l.checked_shl(r.try_into().expect("shift too large")).map(Constant::Int),
BinOpKind::BitXor => Some(Constant::Int(l ^ r)),
BinOpKind::BitOr => Some(Constant::Int(l | r)),
BinOpKind::BitAnd => Some(Constant::Int(l & r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
_ => None,
},
(Constant::F32(l), Some(Constant::F32(r))) => match op.node {
BinOpKind::Add => Some(Constant::F32(l + r)),
BinOpKind::Sub => Some(Constant::F32(l - r)),
BinOpKind::Mul => Some(Constant::F32(l * r)),
BinOpKind::Div => Some(Constant::F32(l / r)),
BinOpKind::Rem => Some(Constant::F32(l % r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
(Constant::F64(l), Some(Constant::F64(r))) => match op.node {
BinOpKind::Add => Some(Constant::F64(l + r)),
BinOpKind::Sub => Some(Constant::F64(l - r)),
BinOpKind::Mul => Some(Constant::F64(l * r)),
BinOpKind::Div => Some(Constant::F64(l / r)),
BinOpKind::Rem => Some(Constant::F64(l % r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
(l, r) => match (op.node, l, r) {
(BinOpKind::And, Constant::Bool(false), _) => Some(Constant::Bool(false)),
(BinOpKind::Or, Constant::Bool(true), _) => Some(Constant::Bool(true)),
(BinOpKind::And, Constant::Bool(true), Some(r)) | (BinOpKind::Or, Constant::Bool(false), Some(r)) => {
Some(r)
},
(BinOpKind::BitXor, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l ^ r)),
(BinOpKind::BitAnd, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l & r)),
(BinOpKind::BitOr, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l | r)),
_ => None,
},
}
}
}
pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
use rustc_middle::mir::interpret::ConstValue;
match result.val {
ty::ConstKind::Value(ConstValue::Scalar(Scalar::Int(int))) => {
match result.ty.kind() {
ty::Bool => Some(Constant::Bool(int == ScalarInt::TRUE)),
ty::Uint(_) | ty::Int(_) => Some(Constant::Int(int.assert_bits(int.size()))),
ty::Float(FloatTy::F32) => Some(Constant::F32(f32::from_bits(
int.try_into().expect("invalid f32 bit representation"),
))),
ty::Float(FloatTy::F64) => Some(Constant::F64(f64::from_bits(
int.try_into().expect("invalid f64 bit representation"),
))),
ty::RawPtr(type_and_mut) => {
if let ty::Uint(_) = type_and_mut.ty.kind() {
return Some(Constant::RawPtr(int.assert_bits(int.size())));
}
None
},
// FIXME: implement other conversions.
_ => None,
}
},
ty::ConstKind::Value(ConstValue::Slice { data, start, end }) => match result.ty.kind() {
ty::Ref(_, tam, _) => match tam.kind() {
ty::Str => String::from_utf8(
data.inspect_with_uninit_and_ptr_outside_interpreter(start..end)
.to_owned(),
)
.ok()
.map(Constant::Str),
_ => None,
},
_ => None,
},
ty::ConstKind::Value(ConstValue::ByRef { alloc, offset: _ }) => match result.ty.kind() {
ty::Array(sub_type, len) => match sub_type.kind() {
ty::Float(FloatTy::F32) => match miri_to_const(len) {
Some(Constant::Int(len)) => alloc
.inspect_with_uninit_and_ptr_outside_interpreter(0..(4 * len as usize))
.to_owned()
.chunks(4)
.map(|chunk| {
Some(Constant::F32(f32::from_le_bytes(
chunk.try_into().expect("this shouldn't happen"),
)))
})
.collect::<Option<Vec<Constant>>>()
.map(Constant::Vec),
_ => None,
},
ty::Float(FloatTy::F64) => match miri_to_const(len) {
Some(Constant::Int(len)) => alloc
.inspect_with_uninit_and_ptr_outside_interpreter(0..(8 * len as usize))
.to_owned()
.chunks(8)
.map(|chunk| {
Some(Constant::F64(f64::from_le_bytes(
chunk.try_into().expect("this shouldn't happen"),
)))
})
.collect::<Option<Vec<Constant>>>()
.map(Constant::Vec),
_ => None,
},
// FIXME: implement other array type conversions.
_ => None,
},
_ => None,
},
// FIXME: implement other conversions.
_ => None,
}
}
pub use clippy_utils::consts::*;

110
clippy_lints/src/lib.rs
View file

@ -50,103 +50,23 @@ use rustc_data_structures::fx::FxHashSet;
use rustc_lint::LintId;
use rustc_session::Session;
/// Macro used to declare a Clippy lint.
///
/// Every lint declaration consists of 4 parts:
///
/// 1. The documentation, which is used for the website
/// 2. The `LINT_NAME`. See [lint naming][lint_naming] on lint naming conventions.
/// 3. The `lint_level`, which is a mapping from *one* of our lint groups to `Allow`, `Warn` or
/// `Deny`. The lint level here has nothing to do with what lint groups the lint is a part of.
/// 4. The `description` that contains a short explanation on what's wrong with code where the
/// lint is triggered.
///
/// Currently the categories `style`, `correctness`, `complexity` and `perf` are enabled by default.
/// As said in the README.md of this repository, if the lint level mapping changes, please update
/// README.md.
///
/// # Example
///
/// ```
/// #![feature(rustc_private)]
/// extern crate rustc_session;
/// use rustc_session::declare_tool_lint;
/// use clippy_lints::declare_clippy_lint;
///
/// declare_clippy_lint! {
/// /// **What it does:** Checks for ... (describe what the lint matches).
/// ///
/// /// **Why is this bad?** Supply the reason for linting the code.
/// ///
/// /// **Known problems:** None. (Or describe where it could go wrong.)
/// ///
/// /// **Example:**
/// ///
/// /// ```rust
/// /// // Bad
/// /// Insert a short example of code that triggers the lint
/// ///
/// /// // Good
/// /// Insert a short example of improved code that doesn't trigger the lint
/// /// ```
/// pub LINT_NAME,
/// pedantic,
/// "description"
/// }
/// ```
/// [lint_naming]: https://rust-lang.github.io/rfcs/0344-conventions-galore.html#lints
#[macro_export]
macro_rules! declare_clippy_lint {
{ $(#[$attr:meta])* pub $name:tt, style, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, correctness, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Deny, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, complexity, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, perf, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, pedantic, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, restriction, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, cargo, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, nursery, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, internal, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, internal_warn, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
( $($x:tt)* ) => { clippy_utils::declare_clippy_lint!($($x)*); }
}
#[macro_export]
macro_rules! sym {
( $($x:tt)* ) => { clippy_utils::sym!($($x)*); }
}
#[macro_export]
macro_rules! unwrap_cargo_metadata {
( $($x:tt)* ) => { clippy_utils::unwrap_cargo_metadata!($($x)*); }
}
macro_rules! extract_msrv_attr {
( $($x:tt)* ) => { clippy_utils::extract_msrv_attr!($($x)*); }
}
mod consts;

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@ -0,0 +1 @@
pub use clippy_utils::*;

24
clippy_utils/Cargo.toml Normal file
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[package]
name = "clippy_utils"
version = "0.1.0"
authors = ["The Rust Project Developers"]
edition = "2018"
[dependencies]
cargo_metadata = "0.12"
if_chain = "1.0.0"
itertools = "0.9"
pulldown-cmark = { version = "0.8", default-features = false }
quine-mc_cluskey = "0.2.2"
regex-syntax = "0.6"
serde = { version = "1.0", features = ["derive"] }
smallvec = { version = "1", features = ["union"] }
toml = "0.5.3"
unicode-normalization = "0.1"
semver = "0.11"
rustc-semver="1.1.0"
# NOTE: cargo requires serde feat in its url dep
# see <https://github.com/rust-lang/rust/pull/63587#issuecomment-522343864>
url = { version = "2.1.0", features = ["serde"] }
quote = "1"
syn = { version = "1", features = ["full"] }

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clippy_lints/src/utils/ast_utils.rs → clippy_utils/src/ast_utils.rs
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@ -4,7 +4,7 @@
#![allow(clippy::similar_names, clippy::wildcard_imports, clippy::enum_glob_use)]
use crate::utils::{both, over};
use crate::{both, over};
use rustc_ast::ptr::P;
use rustc_ast::{self as ast, *};
use rustc_span::symbol::Ident;

0
clippy_lints/src/utils/ast_utils/ident_iter.rs → clippy_utils/src/ast_utils/ident_iter.rs
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0
clippy_lints/src/utils/attrs.rs → clippy_utils/src/attrs.rs
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2
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@ -1,7 +1,7 @@
//! A group of attributes that can be attached to Rust code in order
//! to generate a clippy lint detecting said code automatically.
use crate::utils::get_attr;
use crate::{declare_clippy_lint, get_attr};
use rustc_ast::ast::{Attribute, LitFloatType, LitKind};
use rustc_ast::walk_list;
use rustc_data_structures::fx::FxHashMap;

0
clippy_lints/src/utils/camel_case.rs → clippy_utils/src/camel_case.rs
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0
clippy_lints/src/utils/comparisons.rs → clippy_utils/src/comparisons.rs
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0
clippy_lints/src/utils/conf.rs → clippy_utils/src/conf.rs
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//! This module contains some useful constants.
#![deny(clippy::missing_docs_in_private_items)]
/// List of the built-in types names.
///
/// See also [the reference][reference-types] for a list of such types.
///
/// [reference-types]: https://doc.rust-lang.org/reference/types.html
pub const BUILTIN_TYPES: &[&str] = &[
"i8", "u8", "i16", "u16", "i32", "u32", "i64", "u64", "i128", "u128", "isize", "usize", "f32", "f64", "bool",
"str", "char",
];

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#![allow(clippy::float_cmp)]
use crate::{clip, sext, unsext};
use if_chain::if_chain;
use rustc_ast::ast::{self, LitFloatType, LitKind};
use rustc_data_structures::sync::Lrc;
use rustc_hir::def::{DefKind, Res};
use rustc_hir::{BinOp, BinOpKind, Block, Expr, ExprKind, HirId, QPath, UnOp};
use rustc_lint::LateContext;
use rustc_middle::mir::interpret::Scalar;
use rustc_middle::ty::subst::{Subst, SubstsRef};
use rustc_middle::ty::{self, FloatTy, ScalarInt, Ty, TyCtxt};
use rustc_middle::{bug, span_bug};
use rustc_span::symbol::Symbol;
use std::cmp::Ordering::{self, Equal};
use std::convert::TryInto;
use std::hash::{Hash, Hasher};
/// A `LitKind`-like enum to fold constant `Expr`s into.
#[derive(Debug, Clone)]
pub enum Constant {
/// A `String` (e.g., "abc").
Str(String),
/// A binary string (e.g., `b"abc"`).
Binary(Lrc<[u8]>),
/// A single `char` (e.g., `'a'`).
Char(char),
/// An integer's bit representation.
Int(u128),
/// An `f32`.
F32(f32),
/// An `f64`.
F64(f64),
/// `true` or `false`.
Bool(bool),
/// An array of constants.
Vec(Vec<Constant>),
/// Also an array, but with only one constant, repeated N times.
Repeat(Box<Constant>, u64),
/// A tuple of constants.
Tuple(Vec<Constant>),
/// A raw pointer.
RawPtr(u128),
/// A reference
Ref(Box<Constant>),
/// A literal with syntax error.
Err(Symbol),
}
impl PartialEq for Constant {
fn eq(&self, other: &Self) -> bool {
match (self, other) {
(&Self::Str(ref ls), &Self::Str(ref rs)) => ls == rs,
(&Self::Binary(ref l), &Self::Binary(ref r)) => l == r,
(&Self::Char(l), &Self::Char(r)) => l == r,
(&Self::Int(l), &Self::Int(r)) => l == r,
(&Self::F64(l), &Self::F64(r)) => {
// We want `Fw32 == FwAny` and `FwAny == Fw64`, and by transitivity we must have
// `Fw32 == Fw64`, so don’t compare them.
// `to_bits` is required to catch non-matching 0.0, -0.0, and NaNs.
l.to_bits() == r.to_bits()
},
(&Self::F32(l), &Self::F32(r)) => {
// We want `Fw32 == FwAny` and `FwAny == Fw64`, and by transitivity we must have
// `Fw32 == Fw64`, so don’t compare them.
// `to_bits` is required to catch non-matching 0.0, -0.0, and NaNs.
f64::from(l).to_bits() == f64::from(r).to_bits()
},
(&Self::Bool(l), &Self::Bool(r)) => l == r,
(&Self::Vec(ref l), &Self::Vec(ref r)) | (&Self::Tuple(ref l), &Self::Tuple(ref r)) => l == r,
(&Self::Repeat(ref lv, ref ls), &Self::Repeat(ref rv, ref rs)) => ls == rs && lv == rv,
(&Self::Ref(ref lb), &Self::Ref(ref rb)) => *lb == *rb,
// TODO: are there inter-type equalities?
_ => false,
}
}
}
impl Hash for Constant {
fn hash<H>(&self, state: &mut H)
where
H: Hasher,
{
std::mem::discriminant(self).hash(state);
match *self {
Self::Str(ref s) => {
s.hash(state);
},
Self::Binary(ref b) => {
b.hash(state);
},
Self::Char(c) => {
c.hash(state);
},
Self::Int(i) => {
i.hash(state);
},
Self::F32(f) => {
f64::from(f).to_bits().hash(state);
},
Self::F64(f) => {
f.to_bits().hash(state);
},
Self::Bool(b) => {
b.hash(state);
},
Self::Vec(ref v) | Self::Tuple(ref v) => {
v.hash(state);
},
Self::Repeat(ref c, l) => {
c.hash(state);
l.hash(state);
},
Self::RawPtr(u) => {
u.hash(state);
},
Self::Ref(ref r) => {
r.hash(state);
},
Self::Err(ref s) => {
s.hash(state);
},
}
}
}
impl Constant {
pub fn partial_cmp(tcx: TyCtxt<'_>, cmp_type: Ty<'_>, left: &Self, right: &Self) -> Option<Ordering> {
match (left, right) {
(&Self::Str(ref ls), &Self::Str(ref rs)) => Some(ls.cmp(rs)),
(&Self::Char(ref l), &Self::Char(ref r)) => Some(l.cmp(r)),
(&Self::Int(l), &Self::Int(r)) => {
if let ty::Int(int_ty) = *cmp_type.kind() {
Some(sext(tcx, l, int_ty).cmp(&sext(tcx, r, int_ty)))
} else {
Some(l.cmp(&r))
}
},
(&Self::F64(l), &Self::F64(r)) => l.partial_cmp(&r),
(&Self::F32(l), &Self::F32(r)) => l.partial_cmp(&r),
(&Self::Bool(ref l), &Self::Bool(ref r)) => Some(l.cmp(r)),
(&Self::Tuple(ref l), &Self::Tuple(ref r)) | (&Self::Vec(ref l), &Self::Vec(ref r)) => l
.iter()
.zip(r.iter())
.map(|(li, ri)| Self::partial_cmp(tcx, cmp_type, li, ri))
.find(|r| r.map_or(true, |o| o != Ordering::Equal))
.unwrap_or_else(|| Some(l.len().cmp(&r.len()))),
(&Self::Repeat(ref lv, ref ls), &Self::Repeat(ref rv, ref rs)) => {
match Self::partial_cmp(tcx, cmp_type, lv, rv) {
Some(Equal) => Some(ls.cmp(rs)),
x => x,
}
},
(&Self::Ref(ref lb), &Self::Ref(ref rb)) => Self::partial_cmp(tcx, cmp_type, lb, rb),
// TODO: are there any useful inter-type orderings?
_ => None,
}
}
}
/// Parses a `LitKind` to a `Constant`.
pub fn lit_to_constant(lit: &LitKind, ty: Option<Ty<'_>>) -> Constant {
match *lit {
LitKind::Str(ref is, _) => Constant::Str(is.to_string()),
LitKind::Byte(b) => Constant::Int(u128::from(b)),
LitKind::ByteStr(ref s) => Constant::Binary(Lrc::clone(s)),
LitKind::Char(c) => Constant::Char(c),
LitKind::Int(n, _) => Constant::Int(n),
LitKind::Float(ref is, LitFloatType::Suffixed(fty)) => match fty {
ast::FloatTy::F32 => Constant::F32(is.as_str().parse().unwrap()),
ast::FloatTy::F64 => Constant::F64(is.as_str().parse().unwrap()),
},
LitKind::Float(ref is, LitFloatType::Unsuffixed) => match ty.expect("type of float is known").kind() {
ty::Float(FloatTy::F32) => Constant::F32(is.as_str().parse().unwrap()),
ty::Float(FloatTy::F64) => Constant::F64(is.as_str().parse().unwrap()),
_ => bug!(),
},
LitKind::Bool(b) => Constant::Bool(b),
LitKind::Err(s) => Constant::Err(s),
}
}
pub fn constant<'tcx>(
lcx: &LateContext<'tcx>,
typeck_results: &ty::TypeckResults<'tcx>,
e: &Expr<'_>,
) -> Option<(Constant, bool)> {
let mut cx = ConstEvalLateContext {
lcx,
typeck_results,
param_env: lcx.param_env,
needed_resolution: false,
substs: lcx.tcx.intern_substs(&[]),
};
cx.expr(e).map(|cst| (cst, cx.needed_resolution))
}
pub fn constant_simple<'tcx>(
lcx: &LateContext<'tcx>,
typeck_results: &ty::TypeckResults<'tcx>,
e: &Expr<'_>,
) -> Option<Constant> {
constant(lcx, typeck_results, e).and_then(|(cst, res)| if res { None } else { Some(cst) })
}
/// Creates a `ConstEvalLateContext` from the given `LateContext` and `TypeckResults`.
pub fn constant_context<'a, 'tcx>(
lcx: &'a LateContext<'tcx>,
typeck_results: &'a ty::TypeckResults<'tcx>,
) -> ConstEvalLateContext<'a, 'tcx> {
ConstEvalLateContext {
lcx,
typeck_results,
param_env: lcx.param_env,
needed_resolution: false,
substs: lcx.tcx.intern_substs(&[]),
}
}
pub struct ConstEvalLateContext<'a, 'tcx> {
lcx: &'a LateContext<'tcx>,
typeck_results: &'a ty::TypeckResults<'tcx>,
param_env: ty::ParamEnv<'tcx>,
needed_resolution: bool,
substs: SubstsRef<'tcx>,
}
impl<'a, 'tcx> ConstEvalLateContext<'a, 'tcx> {
/// Simple constant folding: Insert an expression, get a constant or none.
pub fn expr(&mut self, e: &Expr<'_>) -> Option<Constant> {
match e.kind {
ExprKind::Path(ref qpath) => self.fetch_path(qpath, e.hir_id, self.typeck_results.expr_ty(e)),
ExprKind::Block(ref block, _) => self.block(block),
ExprKind::Lit(ref lit) => Some(lit_to_constant(&lit.node, self.typeck_results.expr_ty_opt(e))),
ExprKind::Array(ref vec) => self.multi(vec).map(Constant::Vec),
ExprKind::Tup(ref tup) => self.multi(tup).map(Constant::Tuple),
ExprKind::Repeat(ref value, _) => {
let n = match self.typeck_results.expr_ty(e).kind() {
ty::Array(_, n) => n.try_eval_usize(self.lcx.tcx, self.lcx.param_env)?,
_ => span_bug!(e.span, "typeck error"),
};
self.expr(value).map(|v| Constant::Repeat(Box::new(v), n))
},
ExprKind::Unary(op, ref operand) => self.expr(operand).and_then(|o| match op {
UnOp::Not => self.constant_not(&o, self.typeck_results.expr_ty(e)),
UnOp::Neg => self.constant_negate(&o, self.typeck_results.expr_ty(e)),
UnOp::Deref => Some(if let Constant::Ref(r) = o { *r } else { o }),
}),
ExprKind::If(ref cond, ref then, ref otherwise) => self.ifthenelse(cond, then, *otherwise),
ExprKind::Binary(op, ref left, ref right) => self.binop(op, left, right),
ExprKind::Call(ref callee, ref args) => {
// We only handle a few const functions for now.
if_chain! {
if args.is_empty();
if let ExprKind::Path(qpath) = &callee.kind;
let res = self.typeck_results.qpath_res(qpath, callee.hir_id);
if let Some(def_id) = res.opt_def_id();
let def_path: Vec<_> = self.lcx.get_def_path(def_id).into_iter().map(Symbol::as_str).collect();
let def_path: Vec<&str> = def_path.iter().take(4).map(|s| &**s).collect();
if let ["core", "num", int_impl, "max_value"] = *def_path;
then {
let value = match int_impl {
"<impl i8>" => i8::MAX as u128,
"<impl i16>" => i16::MAX as u128,
"<impl i32>" => i32::MAX as u128,
"<impl i64>" => i64::MAX as u128,
"<impl i128>" => i128::MAX as u128,
_ => return None,
};
Some(Constant::Int(value))
}
else {
None
}
}
},
ExprKind::Index(ref arr, ref index) => self.index(arr, index),
ExprKind::AddrOf(_, _, ref inner) => self.expr(inner).map(|r| Constant::Ref(Box::new(r))),
// TODO: add other expressions.
_ => None,
}
}
#[allow(clippy::cast_possible_wrap)]
fn constant_not(&self, o: &Constant, ty: Ty<'_>) -> Option<Constant> {
use self::Constant::{Bool, Int};
match *o {
Bool(b) => Some(Bool(!b)),
Int(value) => {
let value = !value;
match *ty.kind() {
ty::Int(ity) => Some(Int(unsext(self.lcx.tcx, value as i128, ity))),
ty::Uint(ity) => Some(Int(clip(self.lcx.tcx, value, ity))),
_ => None,
}
},
_ => None,
}
}
fn constant_negate(&self, o: &Constant, ty: Ty<'_>) -> Option<Constant> {
use self::Constant::{Int, F32, F64};
match *o {
Int(value) => {
let ity = match *ty.kind() {
ty::Int(ity) => ity,
_ => return None,
};
// sign extend
let value = sext(self.lcx.tcx, value, ity);
let value = value.checked_neg()?;
// clear unused bits
Some(Int(unsext(self.lcx.tcx, value, ity)))
},
F32(f) => Some(F32(-f)),
F64(f) => Some(F64(-f)),
_ => None,
}
}
/// Create `Some(Vec![..])` of all constants, unless there is any
/// non-constant part.
fn multi(&mut self, vec: &[Expr<'_>]) -> Option<Vec<Constant>> {
vec.iter().map(|elem| self.expr(elem)).collect::<Option<_>>()
}
/// Lookup a possibly constant expression from a `ExprKind::Path`.
fn fetch_path(&mut self, qpath: &QPath<'_>, id: HirId, ty: Ty<'tcx>) -> Option<Constant> {
let res = self.typeck_results.qpath_res(qpath, id);
match res {
Res::Def(DefKind::Const | DefKind::AssocConst, def_id) => {
let substs = self.typeck_results.node_substs(id);
let substs = if self.substs.is_empty() {
substs
} else {
substs.subst(self.lcx.tcx, self.substs)
};
let result = self
.lcx
.tcx
.const_eval_resolve(
self.param_env,
ty::WithOptConstParam::unknown(def_id),
substs,
None,
None,
)
.ok()
.map(|val| rustc_middle::ty::Const::from_value(self.lcx.tcx, val, ty))?;
let result = miri_to_const(&result);
if result.is_some() {
self.needed_resolution = true;
}
result
},
// FIXME: cover all usable cases.
_ => None,
}
}
fn index(&mut self, lhs: &'_ Expr<'_>, index: &'_ Expr<'_>) -> Option<Constant> {
let lhs = self.expr(lhs);
let index = self.expr(index);
match (lhs, index) {
(Some(Constant::Vec(vec)), Some(Constant::Int(index))) => match vec.get(index as usize) {
Some(Constant::F32(x)) => Some(Constant::F32(*x)),
Some(Constant::F64(x)) => Some(Constant::F64(*x)),
_ => None,
},
(Some(Constant::Vec(vec)), _) => {
if !vec.is_empty() && vec.iter().all(|x| *x == vec[0]) {
match vec.get(0) {
Some(Constant::F32(x)) => Some(Constant::F32(*x)),
Some(Constant::F64(x)) => Some(Constant::F64(*x)),
_ => None,
}
} else {
None
}
},
_ => None,
}
}
/// A block can only yield a constant if it only has one constant expression.
fn block(&mut self, block: &Block<'_>) -> Option<Constant> {
if block.stmts.is_empty() {
block.expr.as_ref().and_then(|b| self.expr(b))
} else {
None
}
}
fn ifthenelse(&mut self, cond: &Expr<'_>, then: &Expr<'_>, otherwise: Option<&Expr<'_>>) -> Option<Constant> {
if let Some(Constant::Bool(b)) = self.expr(cond) {
if b {
self.expr(&*then)
} else {
otherwise.as_ref().and_then(|expr| self.expr(expr))
}
} else {
None
}
}
fn binop(&mut self, op: BinOp, left: &Expr<'_>, right: &Expr<'_>) -> Option<Constant> {
let l = self.expr(left)?;
let r = self.expr(right);
match (l, r) {
(Constant::Int(l), Some(Constant::Int(r))) => match *self.typeck_results.expr_ty_opt(left)?.kind() {
ty::Int(ity) => {
let l = sext(self.lcx.tcx, l, ity);
let r = sext(self.lcx.tcx, r, ity);
let zext = |n: i128| Constant::Int(unsext(self.lcx.tcx, n, ity));
match op.node {
BinOpKind::Add => l.checked_add(r).map(zext),
BinOpKind::Sub => l.checked_sub(r).map(zext),
BinOpKind::Mul => l.checked_mul(r).map(zext),
BinOpKind::Div if r != 0 => l.checked_div(r).map(zext),
BinOpKind::Rem if r != 0 => l.checked_rem(r).map(zext),
BinOpKind::Shr => l.checked_shr(r.try_into().expect("invalid shift")).map(zext),
BinOpKind::Shl => l.checked_shl(r.try_into().expect("invalid shift")).map(zext),
BinOpKind::BitXor => Some(zext(l ^ r)),
BinOpKind::BitOr => Some(zext(l | r)),
BinOpKind::BitAnd => Some(zext(l & r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
}
},
ty::Uint(_) => match op.node {
BinOpKind::Add => l.checked_add(r).map(Constant::Int),
BinOpKind::Sub => l.checked_sub(r).map(Constant::Int),
BinOpKind::Mul => l.checked_mul(r).map(Constant::Int),
BinOpKind::Div => l.checked_div(r).map(Constant::Int),
BinOpKind::Rem => l.checked_rem(r).map(Constant::Int),
BinOpKind::Shr => l.checked_shr(r.try_into().expect("shift too large")).map(Constant::Int),
BinOpKind::Shl => l.checked_shl(r.try_into().expect("shift too large")).map(Constant::Int),
BinOpKind::BitXor => Some(Constant::Int(l ^ r)),
BinOpKind::BitOr => Some(Constant::Int(l | r)),
BinOpKind::BitAnd => Some(Constant::Int(l & r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
_ => None,
},
(Constant::F32(l), Some(Constant::F32(r))) => match op.node {
BinOpKind::Add => Some(Constant::F32(l + r)),
BinOpKind::Sub => Some(Constant::F32(l - r)),
BinOpKind::Mul => Some(Constant::F32(l * r)),
BinOpKind::Div => Some(Constant::F32(l / r)),
BinOpKind::Rem => Some(Constant::F32(l % r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
(Constant::F64(l), Some(Constant::F64(r))) => match op.node {
BinOpKind::Add => Some(Constant::F64(l + r)),
BinOpKind::Sub => Some(Constant::F64(l - r)),
BinOpKind::Mul => Some(Constant::F64(l * r)),
BinOpKind::Div => Some(Constant::F64(l / r)),
BinOpKind::Rem => Some(Constant::F64(l % r)),
BinOpKind::Eq => Some(Constant::Bool(l == r)),
BinOpKind::Ne => Some(Constant::Bool(l != r)),
BinOpKind::Lt => Some(Constant::Bool(l < r)),
BinOpKind::Le => Some(Constant::Bool(l <= r)),
BinOpKind::Ge => Some(Constant::Bool(l >= r)),
BinOpKind::Gt => Some(Constant::Bool(l > r)),
_ => None,
},
(l, r) => match (op.node, l, r) {
(BinOpKind::And, Constant::Bool(false), _) => Some(Constant::Bool(false)),
(BinOpKind::Or, Constant::Bool(true), _) => Some(Constant::Bool(true)),
(BinOpKind::And, Constant::Bool(true), Some(r)) | (BinOpKind::Or, Constant::Bool(false), Some(r)) => {
Some(r)
},
(BinOpKind::BitXor, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l ^ r)),
(BinOpKind::BitAnd, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l & r)),
(BinOpKind::BitOr, Constant::Bool(l), Some(Constant::Bool(r))) => Some(Constant::Bool(l | r)),
_ => None,
},
}
}
}
pub fn miri_to_const(result: &ty::Const<'_>) -> Option<Constant> {
use rustc_middle::mir::interpret::ConstValue;
match result.val {
ty::ConstKind::Value(ConstValue::Scalar(Scalar::Int(int))) => {
match result.ty.kind() {
ty::Bool => Some(Constant::Bool(int == ScalarInt::TRUE)),
ty::Uint(_) | ty::Int(_) => Some(Constant::Int(int.assert_bits(int.size()))),
ty::Float(FloatTy::F32) => Some(Constant::F32(f32::from_bits(
int.try_into().expect("invalid f32 bit representation"),
))),
ty::Float(FloatTy::F64) => Some(Constant::F64(f64::from_bits(
int.try_into().expect("invalid f64 bit representation"),
))),
ty::RawPtr(type_and_mut) => {
if let ty::Uint(_) = type_and_mut.ty.kind() {
return Some(Constant::RawPtr(int.assert_bits(int.size())));
}
None
},
// FIXME: implement other conversions.
_ => None,
}
},
ty::ConstKind::Value(ConstValue::Slice { data, start, end }) => match result.ty.kind() {
ty::Ref(_, tam, _) => match tam.kind() {
ty::Str => String::from_utf8(
data.inspect_with_uninit_and_ptr_outside_interpreter(start..end)
.to_owned(),
)
.ok()
.map(Constant::Str),
_ => None,
},
_ => None,
},
ty::ConstKind::Value(ConstValue::ByRef { alloc, offset: _ }) => match result.ty.kind() {
ty::Array(sub_type, len) => match sub_type.kind() {
ty::Float(FloatTy::F32) => match miri_to_const(len) {
Some(Constant::Int(len)) => alloc
.inspect_with_uninit_and_ptr_outside_interpreter(0..(4 * len as usize))
.to_owned()
.chunks(4)
.map(|chunk| {
Some(Constant::F32(f32::from_le_bytes(
chunk.try_into().expect("this shouldn't happen"),
)))
})
.collect::<Option<Vec<Constant>>>()
.map(Constant::Vec),
_ => None,
},
ty::Float(FloatTy::F64) => match miri_to_const(len) {
Some(Constant::Int(len)) => alloc
.inspect_with_uninit_and_ptr_outside_interpreter(0..(8 * len as usize))
.to_owned()
.chunks(8)
.map(|chunk| {
Some(Constant::F64(f64::from_le_bytes(
chunk.try_into().expect("this shouldn't happen"),
)))
})
.collect::<Option<Vec<Constant>>>()
.map(Constant::Vec),
_ => None,
},
// FIXME: implement other array type conversions.
_ => None,
},
_ => None,
},
// FIXME: implement other conversions.
_ => None,
}
}

0
clippy_lints/src/utils/diagnostics.rs → clippy_utils/src/diagnostics.rs
View file

2
clippy_lints/src/utils/eager_or_lazy.rs → clippy_utils/src/eager_or_lazy.rs
View file

@ -9,7 +9,7 @@
//! - or-fun-call
//! - option-if-let-else
use crate::utils::{is_ctor_or_promotable_const_function, is_type_diagnostic_item, match_type, paths};
use crate::{is_ctor_or_promotable_const_function, is_type_diagnostic_item, match_type, paths};
use rustc_hir::def::{DefKind, Res};
use rustc_hir::intravisit;

2
clippy_lints/src/utils/higher.rs → clippy_utils/src/higher.rs
View file

@ -3,7 +3,7 @@
#![deny(clippy::missing_docs_in_private_items)]
use crate::utils::{is_expn_of, match_def_path, paths};
use crate::{is_expn_of, match_def_path, paths};
use if_chain::if_chain;
use rustc_ast::ast;
use rustc_hir as hir;

2
clippy_lints/src/utils/hir_utils.rs → clippy_utils/src/hir_utils.rs
View file

@ -1,5 +1,5 @@
use crate::consts::{constant_context, constant_simple};
use crate::utils::differing_macro_contexts;
use crate::differing_macro_contexts;
use rustc_ast::ast::InlineAsmTemplatePiece;
use rustc_data_structures::fx::FxHashMap;
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};

2
clippy_lints/src/utils/inspector.rs → clippy_utils/src/inspector.rs
View file

@ -1,6 +1,6 @@
//! checks for attributes
use crate::utils::get_attr;
use crate::{declare_clippy_lint, get_attr};
use rustc_ast::ast::{Attribute, InlineAsmTemplatePiece};
use rustc_hir as hir;
use rustc_lint::{LateContext, LateLintPass, LintContext};

2
clippy_lints/src/utils/internal_lints.rs → clippy_utils/src/internal_lints.rs
View file

@ -1,5 +1,5 @@
use crate::consts::{constant_simple, Constant};
use crate::utils::{
use crate::{
is_expn_of, match_def_path, match_qpath, match_type, method_calls, path_to_res, paths, run_lints, snippet,
span_lint, span_lint_and_help, span_lint_and_sugg, SpanlessEq,
};

140
clippy_lints/src/utils/mod.rs → clippy_utils/src/lib.rs
View file

@ -1,3 +1,38 @@
#![feature(bindings_after_at)]
#![feature(box_patterns)]
#![feature(box_syntax)]
#![feature(concat_idents)]
#![feature(crate_visibility_modifier)]
#![feature(drain_filter)]
#![feature(in_band_lifetimes)]
#![feature(once_cell)]
#![feature(or_patterns)]
#![feature(rustc_private)]
#![feature(stmt_expr_attributes)]
#![feature(control_flow_enum)]
extern crate rustc_ast;
extern crate rustc_ast_pretty;
extern crate rustc_attr;
extern crate rustc_data_structures;
extern crate rustc_driver;
extern crate rustc_errors;
extern crate rustc_hir;
extern crate rustc_hir_pretty;
extern crate rustc_index;
extern crate rustc_infer;
extern crate rustc_lexer;
extern crate rustc_lint;
extern crate rustc_middle;
extern crate rustc_mir;
extern crate rustc_parse;
extern crate rustc_parse_format;
extern crate rustc_session;
extern crate rustc_span;
extern crate rustc_target;
extern crate rustc_trait_selection;
extern crate rustc_typeck;
#[macro_use]
pub mod sym_helper;
@ -8,6 +43,7 @@ pub mod author;
pub mod camel_case;
pub mod comparisons;
pub mod conf;
pub mod consts;
mod diagnostics;
pub mod eager_or_lazy;
pub mod higher;
@ -63,6 +99,105 @@ use smallvec::SmallVec;
use crate::consts::{constant, Constant};
/// Macro used to declare a Clippy lint.
///
/// Every lint declaration consists of 4 parts:
///
/// 1. The documentation, which is used for the website
/// 2. The `LINT_NAME`. See [lint naming][lint_naming] on lint naming conventions.
/// 3. The `lint_level`, which is a mapping from *one* of our lint groups to `Allow`, `Warn` or
/// `Deny`. The lint level here has nothing to do with what lint groups the lint is a part of.
/// 4. The `description` that contains a short explanation on what's wrong with code where the
/// lint is triggered.
///
/// Currently the categories `style`, `correctness`, `complexity` and `perf` are enabled by default.
/// As said in the README.md of this repository, if the lint level mapping changes, please update
/// README.md.
///
/// # Example
///
/// ```
/// #![feature(rustc_private)]
/// extern crate rustc_session;
/// use rustc_session::declare_tool_lint;
/// use clippy_lints::declare_clippy_lint;
///
/// declare_clippy_lint! {
/// /// **What it does:** Checks for ... (describe what the lint matches).
/// ///
/// /// **Why is this bad?** Supply the reason for linting the code.
/// ///
/// /// **Known problems:** None. (Or describe where it could go wrong.)
/// ///
/// /// **Example:**
/// ///
/// /// ```rust
/// /// // Bad
/// /// Insert a short example of code that triggers the lint
/// ///
/// /// // Good
/// /// Insert a short example of improved code that doesn't trigger the lint
/// /// ```
/// pub LINT_NAME,
/// pedantic,
/// "description"
/// }
/// ```
/// [lint_naming]: https://rust-lang.github.io/rfcs/0344-conventions-galore.html#lints
#[macro_export]
macro_rules! declare_clippy_lint {
{ $(#[$attr:meta])* pub $name:tt, style, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, correctness, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Deny, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, complexity, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, perf, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, pedantic, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, restriction, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, cargo, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, nursery, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, internal, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Allow, $description, report_in_external_macro: true
}
};
{ $(#[$attr:meta])* pub $name:tt, internal_warn, $description:tt } => {
declare_tool_lint! {
$(#[$attr])* pub clippy::$name, Warn, $description, report_in_external_macro: true
}
};
}
pub fn parse_msrv(msrv: &str, sess: Option<&Session>, span: Option<Span>) -> Option<RustcVersion> {
if let Ok(version) = RustcVersion::parse(msrv) {
return Some(version);
@ -78,6 +213,7 @@ pub fn meets_msrv(msrv: Option<&RustcVersion>, lint_msrv: &RustcVersion) -> bool
msrv.map_or(true, |msrv| msrv.meets(*lint_msrv))
}
#[macro_export]
macro_rules! extract_msrv_attr {
(LateContext) => {
extract_msrv_attr!(@LateContext, ());
@ -87,11 +223,11 @@ macro_rules! extract_msrv_attr {
};
(@$context:ident$(, $call:tt)?) => {
fn enter_lint_attrs(&mut self, cx: &rustc_lint::$context<'tcx>, attrs: &'tcx [rustc_ast::ast::Attribute]) {
use $crate::utils::get_unique_inner_attr;
use $crate::get_unique_inner_attr;
match get_unique_inner_attr(cx.sess$($call)?, attrs, "msrv") {
Some(msrv_attr) => {
if let Some(msrv) = msrv_attr.value_str() {
self.msrv = $crate::utils::parse_msrv(
self.msrv = $crate::parse_msrv(
&msrv.to_string(),
Some(cx.sess$($call)?),
Some(msrv_attr.span),

0
clippy_lints/src/utils/numeric_literal.rs → clippy_utils/src/numeric_literal.rs
View file

0
clippy_lints/src/utils/paths.rs → clippy_utils/src/paths.rs
View file

2
clippy_lints/src/utils/ptr.rs → clippy_utils/src/ptr.rs
View file

@ -1,4 +1,4 @@
use crate::utils::{get_pat_name, match_var, snippet};
use crate::{get_pat_name, match_var, snippet};
use rustc_hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
use rustc_hir::{Body, BodyId, Expr, ExprKind, Param};
use rustc_lint::LateContext;

0
clippy_lints/src/utils/qualify_min_const_fn.rs → clippy_utils/src/qualify_min_const_fn.rs
View file

2
clippy_lints/src/utils/sugg.rs → clippy_utils/src/sugg.rs
View file

@ -1,7 +1,7 @@
//! Contains utility functions to generate suggestions.
#![deny(clippy::missing_docs_in_private_items)]
use crate::utils::{higher, snippet, snippet_opt, snippet_with_macro_callsite};
use crate::{higher, snippet, snippet_opt, snippet_with_macro_callsite};
use rustc_ast::util::parser::AssocOp;
use rustc_ast::{ast, token};
use rustc_ast_pretty::pprust::token_kind_to_string;

0
clippy_lints/src/utils/sym_helper.rs → clippy_utils/src/sym_helper.rs
View file

2
clippy_lints/src/utils/usage.rs → clippy_utils/src/usage.rs
View file

@ -1,4 +1,4 @@
use crate::utils;
use crate as utils;
use rustc_data_structures::fx::FxHashSet;
use rustc_hir as hir;
use rustc_hir::def::Res;

0
clippy_lints/src/utils/visitors.rs → clippy_utils/src/visitors.rs
View file