+// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
//! Contains utility functions to generate suggestions.
-#![deny(missing_docs_in_private_items)]
-// currently ignores lifetimes and generics
-#![allow(use_self)]
+#![deny(clippy::missing_docs_in_private_items)]
+use crate::utils::{higher, in_macro, snippet, snippet_opt};
+use matches::matches;
use rustc::hir;
use rustc::lint::{EarlyContext, LateContext, LintContext};
use rustc_errors;
+use rustc_errors::Applicability;
+use std;
use std::borrow::Cow;
+use std::convert::TryInto;
use std::fmt::Display;
-use std;
-use syntax::codemap::{CharPos, Span};
+use syntax::ast;
use syntax::parse::token;
use syntax::print::pprust::token_to_string;
+use syntax::source_map::{CharPos, Span};
use syntax::util::parser::AssocOp;
-use syntax::ast;
-use crate::utils::{higher, snippet, snippet_opt};
use syntax_pos::{BytePos, Pos};
/// A helper type to build suggestion correctly handling parenthesis.
/// Literal constant `1`, for convenience.
pub const ONE: Sugg<'static> = Sugg::NonParen(Cow::Borrowed("1"));
-impl<'a> Display for Sugg<'a> {
- fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+impl Display for Sugg<'_> {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
match *self {
Sugg::NonParen(ref s) | Sugg::MaybeParen(ref s) | Sugg::BinOp(_, ref s) => s.fmt(f),
}
}
}
-#[allow(wrong_self_convention)] // ok, because of the function `as_ty` method
+#[allow(clippy::wrong_self_convention)] // ok, because of the function `as_ty` method
impl<'a> Sugg<'a> {
/// Prepare a suggestion from an expression.
- pub fn hir_opt(cx: &LateContext, expr: &hir::Expr) -> Option<Self> {
+ pub fn hir_opt(cx: &LateContext<'_, '_>, expr: &hir::Expr) -> Option<Self> {
snippet_opt(cx, expr.span).map(|snippet| {
let snippet = Cow::Owned(snippet);
match expr.node {
- hir::ExprAddrOf(..) |
- hir::ExprBox(..) |
- hir::ExprClosure(.., _) |
- hir::ExprIf(..) |
- hir::ExprUnary(..) |
- hir::ExprMatch(..) => Sugg::MaybeParen(snippet),
- hir::ExprContinue(..) |
- hir::ExprYield(..) |
- hir::ExprArray(..) |
- hir::ExprBlock(..) |
- hir::ExprBreak(..) |
- hir::ExprCall(..) |
- hir::ExprField(..) |
- hir::ExprIndex(..) |
- hir::ExprInlineAsm(..) |
- hir::ExprLit(..) |
- hir::ExprLoop(..) |
- hir::ExprMethodCall(..) |
- hir::ExprPath(..) |
- hir::ExprRepeat(..) |
- hir::ExprRet(..) |
- hir::ExprStruct(..) |
- hir::ExprTup(..) |
- hir::ExprWhile(..) => Sugg::NonParen(snippet),
- hir::ExprAssign(..) => Sugg::BinOp(AssocOp::Assign, snippet),
- hir::ExprAssignOp(op, ..) => Sugg::BinOp(hirbinop2assignop(op), snippet),
- hir::ExprBinary(op, ..) => Sugg::BinOp(AssocOp::from_ast_binop(higher::binop(op.node)), snippet),
- hir::ExprCast(..) => Sugg::BinOp(AssocOp::As, snippet),
- hir::ExprType(..) => Sugg::BinOp(AssocOp::Colon, snippet),
+ hir::ExprKind::AddrOf(..)
+ | hir::ExprKind::Box(..)
+ | hir::ExprKind::Closure(.., _)
+ | hir::ExprKind::If(..)
+ | hir::ExprKind::Unary(..)
+ | hir::ExprKind::Match(..) => Sugg::MaybeParen(snippet),
+ hir::ExprKind::Continue(..)
+ | hir::ExprKind::Yield(..)
+ | hir::ExprKind::Array(..)
+ | hir::ExprKind::Block(..)
+ | hir::ExprKind::Break(..)
+ | hir::ExprKind::Call(..)
+ | hir::ExprKind::Field(..)
+ | hir::ExprKind::Index(..)
+ | hir::ExprKind::InlineAsm(..)
+ | hir::ExprKind::Lit(..)
+ | hir::ExprKind::Loop(..)
+ | hir::ExprKind::MethodCall(..)
+ | hir::ExprKind::Path(..)
+ | hir::ExprKind::Repeat(..)
+ | hir::ExprKind::Ret(..)
+ | hir::ExprKind::Struct(..)
+ | hir::ExprKind::Tup(..)
+ | hir::ExprKind::While(..)
+ | hir::ExprKind::Err => Sugg::NonParen(snippet),
+ hir::ExprKind::Assign(..) => Sugg::BinOp(AssocOp::Assign, snippet),
+ hir::ExprKind::AssignOp(op, ..) => Sugg::BinOp(hirbinop2assignop(op), snippet),
+ hir::ExprKind::Binary(op, ..) => Sugg::BinOp(AssocOp::from_ast_binop(higher::binop(op.node)), snippet),
+ hir::ExprKind::Cast(..) => Sugg::BinOp(AssocOp::As, snippet),
+ hir::ExprKind::Type(..) => Sugg::BinOp(AssocOp::Colon, snippet),
}
})
}
/// Convenience function around `hir_opt` for suggestions with a default
/// text.
- pub fn hir(cx: &LateContext, expr: &hir::Expr, default: &'a str) -> Self {
+ pub fn hir(cx: &LateContext<'_, '_>, expr: &hir::Expr, default: &'a str) -> Self {
Self::hir_opt(cx, expr).unwrap_or_else(|| Sugg::NonParen(Cow::Borrowed(default)))
}
+ /// Same as `hir`, but it adapts the applicability level by following rules:
+ ///
+ /// - Applicability level `Unspecified` will never be changed.
+ /// - If the span is inside a macro, change the applicability level to `MaybeIncorrect`.
+ /// - If the default value is used and the applicability level is `MachineApplicable`, change it
+ /// to
+ /// `HasPlaceholders`
+ pub fn hir_with_applicability(
+ cx: &LateContext<'_, '_>,
+ expr: &hir::Expr,
+ default: &'a str,
+ applicability: &mut Applicability,
+ ) -> Self {
+ if *applicability != Applicability::Unspecified && in_macro(expr.span) {
+ *applicability = Applicability::MaybeIncorrect;
+ }
+ Self::hir_opt(cx, expr).unwrap_or_else(|| {
+ if *applicability == Applicability::MachineApplicable {
+ *applicability = Applicability::HasPlaceholders;
+ }
+ Sugg::NonParen(Cow::Borrowed(default))
+ })
+ }
+
/// Prepare a suggestion from an expression.
- pub fn ast(cx: &EarlyContext, expr: &ast::Expr, default: &'a str) -> Self {
+ pub fn ast(cx: &EarlyContext<'_>, expr: &ast::Expr, default: &'a str) -> Self {
use syntax::ast::RangeLimits;
let snippet = snippet(cx, expr.span, default);
match expr.node {
- ast::ExprKind::AddrOf(..) |
- ast::ExprKind::Box(..) |
- ast::ExprKind::Closure(..) |
- ast::ExprKind::If(..) |
- ast::ExprKind::IfLet(..) |
- ast::ExprKind::ObsoleteInPlace(..) |
- ast::ExprKind::Unary(..) |
- ast::ExprKind::Match(..) => Sugg::MaybeParen(snippet),
- ast::ExprKind::Block(..) |
- ast::ExprKind::Break(..) |
- ast::ExprKind::Call(..) |
- ast::ExprKind::Catch(..) |
- ast::ExprKind::Continue(..) |
- ast::ExprKind::Yield(..) |
- ast::ExprKind::Field(..) |
- ast::ExprKind::ForLoop(..) |
- ast::ExprKind::Index(..) |
- ast::ExprKind::InlineAsm(..) |
- ast::ExprKind::Lit(..) |
- ast::ExprKind::Loop(..) |
- ast::ExprKind::Mac(..) |
- ast::ExprKind::MethodCall(..) |
- ast::ExprKind::Paren(..) |
- ast::ExprKind::Path(..) |
- ast::ExprKind::Repeat(..) |
- ast::ExprKind::Ret(..) |
- ast::ExprKind::Struct(..) |
- ast::ExprKind::Try(..) |
- ast::ExprKind::Tup(..) |
- ast::ExprKind::Array(..) |
- ast::ExprKind::While(..) |
- ast::ExprKind::WhileLet(..) => Sugg::NonParen(snippet),
+ ast::ExprKind::AddrOf(..)
+ | ast::ExprKind::Box(..)
+ | ast::ExprKind::Closure(..)
+ | ast::ExprKind::If(..)
+ | ast::ExprKind::IfLet(..)
+ | ast::ExprKind::ObsoleteInPlace(..)
+ | ast::ExprKind::Unary(..)
+ | ast::ExprKind::Match(..) => Sugg::MaybeParen(snippet),
+ ast::ExprKind::Async(..)
+ | ast::ExprKind::Block(..)
+ | ast::ExprKind::Break(..)
+ | ast::ExprKind::Call(..)
+ | ast::ExprKind::Continue(..)
+ | ast::ExprKind::Yield(..)
+ | ast::ExprKind::Field(..)
+ | ast::ExprKind::ForLoop(..)
+ | ast::ExprKind::Index(..)
+ | ast::ExprKind::InlineAsm(..)
+ | ast::ExprKind::Lit(..)
+ | ast::ExprKind::Loop(..)
+ | ast::ExprKind::Mac(..)
+ | ast::ExprKind::MethodCall(..)
+ | ast::ExprKind::Paren(..)
+ | ast::ExprKind::Path(..)
+ | ast::ExprKind::Repeat(..)
+ | ast::ExprKind::Ret(..)
+ | ast::ExprKind::Struct(..)
+ | ast::ExprKind::Try(..)
+ | ast::ExprKind::TryBlock(..)
+ | ast::ExprKind::Tup(..)
+ | ast::ExprKind::Array(..)
+ | ast::ExprKind::While(..)
+ | ast::ExprKind::WhileLet(..)
+ | ast::ExprKind::Err => Sugg::NonParen(snippet),
ast::ExprKind::Range(.., RangeLimits::HalfOpen) => Sugg::BinOp(AssocOp::DotDot, snippet),
ast::ExprKind::Range(.., RangeLimits::Closed) => Sugg::BinOp(AssocOp::DotDotEq, snippet),
ast::ExprKind::Assign(..) => Sugg::BinOp(AssocOp::Assign, snippet),
make_binop(ast::BinOpKind::And, &self, rhs)
}
+ /// Convenience method to create the `<lhs> & <rhs>` suggestion.
+ pub fn bit_and(self, rhs: &Self) -> Sugg<'static> {
+ make_binop(ast::BinOpKind::BitAnd, &self, rhs)
+ }
+
/// Convenience method to create the `<lhs> as <rhs>` suggestion.
pub fn as_ty<R: Display>(self, rhs: R) -> Sugg<'static> {
make_assoc(AssocOp::As, &self, &Sugg::NonParen(rhs.to_string().into()))
/// Convenience method to create the `<lhs>..<rhs>` or `<lhs>...<rhs>`
/// suggestion.
+ #[allow(dead_code)]
pub fn range(self, end: &Self, limit: ast::RangeLimits) -> Sugg<'static> {
match limit {
ast::RangeLimits::HalfOpen => make_assoc(AssocOp::DotDot, &self, end),
match self {
Sugg::NonParen(..) => self,
// (x) and (x).y() both don't need additional parens
- Sugg::MaybeParen(sugg) => if sugg.starts_with('(') && sugg.ends_with(')') {
- Sugg::MaybeParen(sugg)
- } else {
- Sugg::NonParen(format!("({})", sugg).into())
+ Sugg::MaybeParen(sugg) => {
+ if sugg.starts_with('(') && sugg.ends_with(')') {
+ Sugg::MaybeParen(sugg)
+ } else {
+ Sugg::NonParen(format!("({})", sugg).into())
+ }
},
Sugg::BinOp(_, sugg) => Sugg::NonParen(format!("({})", sugg).into()),
}
impl<T> ParenHelper<T> {
/// Build a `ParenHelper`.
fn new(paren: bool, wrapped: T) -> Self {
- Self {
- paren,
- wrapped,
- }
+ Self { paren, wrapped }
}
}
impl<T: Display> Display for ParenHelper<T> {
- fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
if self.paren {
write!(f, "({})", self.wrapped)
} else {
/// For convenience, the operator is taken as a string because all unary
/// operators have the same
/// precedence.
-pub fn make_unop(op: &str, expr: Sugg) -> Sugg<'static> {
+pub fn make_unop(op: &str, expr: Sugg<'_>) -> Sugg<'static> {
Sugg::MaybeParen(format!("{}{}", op, expr.maybe_par()).into())
}
/// Precedence of shift operator relative to other arithmetic operation is
/// often confusing so
/// parenthesis will always be added for a mix of these.
-pub fn make_assoc(op: AssocOp, lhs: &Sugg, rhs: &Sugg) -> Sugg<'static> {
+pub fn make_assoc(op: AssocOp, lhs: &Sugg<'_>, rhs: &Sugg<'_>) -> Sugg<'static> {
/// Whether the operator is a shift operator `<<` or `>>`.
fn is_shift(op: &AssocOp) -> bool {
matches!(*op, AssocOp::ShiftLeft | AssocOp::ShiftRight)
|| (other.precedence() == op.precedence()
&& ((op != other && associativity(op) != dir)
|| (op == other && associativity(op) != Associativity::Both)))
- || is_shift(op) && is_arith(other) || is_shift(other) && is_arith(op)
+ || is_shift(op) && is_arith(other)
+ || is_shift(other) && is_arith(op)
}
let lhs_paren = if let Sugg::BinOp(ref lop, _) = *lhs {
let lhs = ParenHelper::new(lhs_paren, lhs);
let rhs = ParenHelper::new(rhs_paren, rhs);
let sugg = match op {
- AssocOp::Add |
- AssocOp::BitAnd |
- AssocOp::BitOr |
- AssocOp::BitXor |
- AssocOp::Divide |
- AssocOp::Equal |
- AssocOp::Greater |
- AssocOp::GreaterEqual |
- AssocOp::LAnd |
- AssocOp::LOr |
- AssocOp::Less |
- AssocOp::LessEqual |
- AssocOp::Modulus |
- AssocOp::Multiply |
- AssocOp::NotEqual |
- AssocOp::ShiftLeft |
- AssocOp::ShiftRight |
- AssocOp::Subtract => format!("{} {} {}", lhs, op.to_ast_binop().expect("Those are AST ops").to_string(), rhs),
+ AssocOp::Add
+ | AssocOp::BitAnd
+ | AssocOp::BitOr
+ | AssocOp::BitXor
+ | AssocOp::Divide
+ | AssocOp::Equal
+ | AssocOp::Greater
+ | AssocOp::GreaterEqual
+ | AssocOp::LAnd
+ | AssocOp::LOr
+ | AssocOp::Less
+ | AssocOp::LessEqual
+ | AssocOp::Modulus
+ | AssocOp::Multiply
+ | AssocOp::NotEqual
+ | AssocOp::ShiftLeft
+ | AssocOp::ShiftRight
+ | AssocOp::Subtract => format!(
+ "{} {} {}",
+ lhs,
+ op.to_ast_binop().expect("Those are AST ops").to_string(),
+ rhs
+ ),
AssocOp::Assign => format!("{} = {}", lhs, rhs),
AssocOp::ObsoleteInPlace => format!("in ({}) {}", lhs, rhs),
AssocOp::AssignOp(op) => format!("{} {}= {}", lhs, token_to_string(&token::BinOp(op)), rhs),
Sugg::BinOp(op, sugg.into())
}
-/// Convinience wrapper arround `make_assoc` and `AssocOp::from_ast_binop`.
-pub fn make_binop(op: ast::BinOpKind, lhs: &Sugg, rhs: &Sugg) -> Sugg<'static> {
+/// Convenience wrapper around `make_assoc` and `AssocOp::from_ast_binop`.
+pub fn make_binop(op: ast::BinOpKind, lhs: &Sugg<'_>, rhs: &Sugg<'_>) -> Sugg<'static> {
make_assoc(AssocOp::from_ast_binop(op), lhs, rhs)
}
match *op {
ObsoleteInPlace | Assign | AssignOp(_) => Associativity::Right,
Add | BitAnd | BitOr | BitXor | LAnd | LOr | Multiply | As | Colon => Associativity::Both,
- Divide |
- Equal |
- Greater |
- GreaterEqual |
- Less |
- LessEqual |
- Modulus |
- NotEqual |
- ShiftLeft |
- ShiftRight |
- Subtract => Associativity::Left,
+ Divide | Equal | Greater | GreaterEqual | Less | LessEqual | Modulus | NotEqual | ShiftLeft | ShiftRight
+ | Subtract => Associativity::Left,
DotDot | DotDotEq => Associativity::None,
}
}
/// Convert a `hir::BinOp` to the corresponding assigning binary operator.
fn hirbinop2assignop(op: hir::BinOp) -> AssocOp {
- use rustc::hir::BinOp_::*;
use syntax::parse::token::BinOpToken::*;
AssocOp::AssignOp(match op.node {
- BiAdd => Plus,
- BiBitAnd => And,
- BiBitOr => Or,
- BiBitXor => Caret,
- BiDiv => Slash,
- BiMul => Star,
- BiRem => Percent,
- BiShl => Shl,
- BiShr => Shr,
- BiSub => Minus,
- BiAnd | BiEq | BiGe | BiGt | BiLe | BiLt | BiNe | BiOr => panic!("This operator does not exist"),
+ hir::BinOpKind::Add => Plus,
+ hir::BinOpKind::BitAnd => And,
+ hir::BinOpKind::BitOr => Or,
+ hir::BinOpKind::BitXor => Caret,
+ hir::BinOpKind::Div => Slash,
+ hir::BinOpKind::Mul => Star,
+ hir::BinOpKind::Rem => Percent,
+ hir::BinOpKind::Shl => Shl,
+ hir::BinOpKind::Shr => Shr,
+ hir::BinOpKind::Sub => Minus,
+
+ hir::BinOpKind::And
+ | hir::BinOpKind::Eq
+ | hir::BinOpKind::Ge
+ | hir::BinOpKind::Gt
+ | hir::BinOpKind::Le
+ | hir::BinOpKind::Lt
+ | hir::BinOpKind::Ne
+ | hir::BinOpKind::Or => panic!("This operator does not exist"),
})
}
/// Return the indentation before `span` if there are nothing but `[ \t]`
/// before it on its line.
fn indentation<'a, T: LintContext<'a>>(cx: &T, span: Span) -> Option<String> {
- let lo = cx.sess().codemap().lookup_char_pos(span.lo());
- if let Some(line) = lo.file
- .get_line(lo.line - 1 /* line numbers in `Loc` are 1-based */)
- {
+ let lo = cx.sess().source_map().lookup_char_pos(span.lo());
+ if let Some(line) = lo.file.get_line(lo.line - 1 /* line numbers in `Loc` are 1-based */) {
if let Some((pos, _)) = line.char_indices().find(|&(_, c)| c != ' ' && c != '\t') {
// we can mix char and byte positions here because we only consider `[ \t]`
if lo.col == CharPos(pos) {
/// ```rust,ignore
/// db.suggest_item_with_attr(cx, item, "#[derive(Default)]");
/// ```
- fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D);
+ fn suggest_item_with_attr<D: Display + ?Sized>(
+ &mut self,
+ cx: &T,
+ item: Span,
+ msg: &str,
+ attr: &D,
+ applicability: Applicability,
+ );
/// Suggest to add an item before another.
///
/// bar();
/// }");
/// ```
- fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str);
+ fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str, applicability: Applicability);
/// Suggest to completely remove an item.
///
/// ```rust,ignore
/// db.suggest_remove_item(cx, item, "remove this")
/// ```
- fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str);
+ fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str, applicability: Applicability);
}
impl<'a, 'b, 'c, T: LintContext<'c>> DiagnosticBuilderExt<'c, T> for rustc_errors::DiagnosticBuilder<'b> {
- fn suggest_item_with_attr<D: Display + ?Sized>(&mut self, cx: &T, item: Span, msg: &str, attr: &D) {
+ fn suggest_item_with_attr<D: Display + ?Sized>(
+ &mut self,
+ cx: &T,
+ item: Span,
+ msg: &str,
+ attr: &D,
+ applicability: Applicability,
+ ) {
if let Some(indent) = indentation(cx, item) {
let span = item.with_hi(item.lo());
- self.span_suggestion(span, msg, format!("{}\n{}", attr, indent));
+ self.span_suggestion_with_applicability(span, msg, format!("{}\n{}", attr, indent), applicability);
}
}
- fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str) {
+ fn suggest_prepend_item(&mut self, cx: &T, item: Span, msg: &str, new_item: &str, applicability: Applicability) {
if let Some(indent) = indentation(cx, item) {
let span = item.with_hi(item.lo());
})
.collect::<String>();
- self.span_suggestion(span, msg, format!("{}\n{}", new_item, indent));
+ self.span_suggestion_with_applicability(span, msg, format!("{}\n{}", new_item, indent), applicability);
}
}
- fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str) {
+ fn suggest_remove_item(&mut self, cx: &T, item: Span, msg: &str, applicability: Applicability) {
let mut remove_span = item;
- let hi = cx.sess().codemap().next_point(remove_span).hi();
- let fmpos = cx.sess().codemap().lookup_byte_offset(hi);
+ let hi = cx.sess().source_map().next_point(remove_span).hi();
+ let fmpos = cx.sess().source_map().lookup_byte_offset(hi);
- if let Some(ref src) = fmpos.fm.src {
+ if let Some(ref src) = fmpos.sf.src {
let non_whitespace_offset = src[fmpos.pos.to_usize()..].find(|c| c != ' ' && c != '\t' && c != '\n');
if let Some(non_whitespace_offset) = non_whitespace_offset {
- remove_span = remove_span.with_hi(remove_span.hi() + BytePos(non_whitespace_offset as u32))
+ remove_span = remove_span
+ .with_hi(remove_span.hi() + BytePos(non_whitespace_offset.try_into().expect("offset too large")))
}
}
- self.span_suggestion(remove_span, msg, String::new());
+ self.span_suggestion_with_applicability(remove_span, msg, String::new(), applicability);
}
}