-// 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.
-
-
-use crate::rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass, LintContext, in_external_macro};
-use crate::rustc::{declare_tool_lint, lint_array};
-use crate::rustc_data_structures::fx::FxHashMap;
+use crate::utils::{
+ constants, snippet, snippet_opt, span_help_and_lint, span_lint, span_lint_and_sugg, span_lint_and_then,
+};
use if_chain::if_chain;
-use std::char;
-use crate::syntax::ast::*;
-use crate::syntax::source_map::Span;
-use crate::syntax::visit::{FnKind, Visitor, walk_expr};
-use crate::utils::{constants, snippet, snippet_opt, span_help_and_lint, span_lint, span_lint_and_then};
-use crate::rustc_errors::Applicability;
+use rustc::lint::{in_external_macro, EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass};
+use rustc::{declare_lint_pass, declare_tool_lint};
+use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::Applicability;
+use syntax::ast::*;
+use syntax::source_map::Span;
+use syntax::visit::{walk_expr, FnKind, Visitor};
-/// **What it does:** Checks for structure field patterns bound to wildcards.
-///
-/// **Why is this bad?** Using `..` instead is shorter and leaves the focus on
-/// the fields that are actually bound.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// let { a: _, b: ref b, c: _ } = ..
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for structure field patterns bound to wildcards.
+ ///
+ /// **Why is this bad?** Using `..` instead is shorter and leaves the focus on
+ /// the fields that are actually bound.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```ignore
+ /// let { a: _, b: ref b, c: _ } = ..
+ /// ```
pub UNNEEDED_FIELD_PATTERN,
style,
"struct fields bound to a wildcard instead of using `..`"
}
-/// **What it does:** Checks for function arguments having the similar names
-/// differing by an underscore.
-///
-/// **Why is this bad?** It affects code readability.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// fn foo(a: i32, _a: i32) {}
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for function arguments having the similar names
+ /// differing by an underscore.
+ ///
+ /// **Why is this bad?** It affects code readability.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// fn foo(a: i32, _a: i32) {}
+ /// ```
pub DUPLICATE_UNDERSCORE_ARGUMENT,
style,
"function arguments having names which only differ by an underscore"
}
-/// **What it does:** Detects closures called in the same expression where they
-/// are defined.
-///
-/// **Why is this bad?** It is unnecessarily adding to the expression's
-/// complexity.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// (|| 42)()
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Detects closures called in the same expression where they
+ /// are defined.
+ ///
+ /// **Why is this bad?** It is unnecessarily adding to the expression's
+ /// complexity.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust,ignore
+ /// (|| 42)()
+ /// ```
pub REDUNDANT_CLOSURE_CALL,
complexity,
"throwaway closures called in the expression they are defined"
}
-/// **What it does:** Detects expressions of the form `--x`.
-///
-/// **Why is this bad?** It can mislead C/C++ programmers to think `x` was
-/// decremented.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// --x;
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Detects expressions of the form `--x`.
+ ///
+ /// **Why is this bad?** It can mislead C/C++ programmers to think `x` was
+ /// decremented.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// let mut x = 3;
+ /// --x;
+ /// ```
pub DOUBLE_NEG,
style,
"`--x`, which is a double negation of `x` and not a pre-decrement as in C/C++"
}
-/// **What it does:** Warns on hexadecimal literals with mixed-case letter
-/// digits.
-///
-/// **Why is this bad?** It looks confusing.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// let y = 0x1a9BAcD;
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Warns on hexadecimal literals with mixed-case letter
+ /// digits.
+ ///
+ /// **Why is this bad?** It looks confusing.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// let y = 0x1a9BAcD;
+ /// ```
pub MIXED_CASE_HEX_LITERALS,
style,
"hex literals whose letter digits are not consistently upper- or lowercased"
}
-/// **What it does:** Warns if literal suffixes are not separated by an
-/// underscore.
-///
-/// **Why is this bad?** It is much less readable.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// let y = 123832i32;
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Warns if literal suffixes are not separated by an
+ /// underscore.
+ ///
+ /// **Why is this bad?** It is much less readable.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// let y = 123832i32;
+ /// ```
pub UNSEPARATED_LITERAL_SUFFIX,
pedantic,
"literals whose suffix is not separated by an underscore"
}
-/// **What it does:** Warns if an integral constant literal starts with `0`.
-///
-/// **Why is this bad?** In some languages (including the infamous C language
-/// and most of its
-/// family), this marks an octal constant. In Rust however, this is a decimal
-/// constant. This could
-/// be confusing for both the writer and a reader of the constant.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-///
-/// In Rust:
-/// ```rust
-/// fn main() {
-/// let a = 0123;
-/// println!("{}", a);
-/// }
-/// ```
-///
-/// prints `123`, while in C:
-///
-/// ```c
-/// #include <stdio.h>
-///
-/// int main() {
-/// int a = 0123;
-/// printf("%d\n", a);
-/// }
-/// ```
-///
-/// prints `83` (as `83 == 0o123` while `123 == 0o173`).
declare_clippy_lint! {
+ /// **What it does:** Warns if an integral constant literal starts with `0`.
+ ///
+ /// **Why is this bad?** In some languages (including the infamous C language
+ /// and most of its
+ /// family), this marks an octal constant. In Rust however, this is a decimal
+ /// constant. This could
+ /// be confusing for both the writer and a reader of the constant.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ ///
+ /// In Rust:
+ /// ```rust
+ /// fn main() {
+ /// let a = 0123;
+ /// println!("{}", a);
+ /// }
+ /// ```
+ ///
+ /// prints `123`, while in C:
+ ///
+ /// ```c
+ /// #include <stdio.h>
+ ///
+ /// int main() {
+ /// int a = 0123;
+ /// printf("%d\n", a);
+ /// }
+ /// ```
+ ///
+ /// prints `83` (as `83 == 0o123` while `123 == 0o173`).
pub ZERO_PREFIXED_LITERAL,
complexity,
"integer literals starting with `0`"
}
-/// **What it does:** Warns if a generic shadows a built-in type.
-///
-/// **Why is this bad?** This gives surprising type errors.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-///
-/// ```rust
-/// impl<u32> Foo<u32> {
-/// fn impl_func(&self) -> u32 {
-/// 42
-/// }
-/// }
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Warns if a generic shadows a built-in type.
+ ///
+ /// **Why is this bad?** This gives surprising type errors.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ ///
+ /// ```ignore
+ /// impl<u32> Foo<u32> {
+ /// fn impl_func(&self) -> u32 {
+ /// 42
+ /// }
+ /// }
+ /// ```
pub BUILTIN_TYPE_SHADOW,
style,
"shadowing a builtin type"
}
-#[derive(Copy, Clone)]
-pub struct MiscEarly;
-
-impl LintPass for MiscEarly {
- fn get_lints(&self) -> LintArray {
- lint_array!(
- UNNEEDED_FIELD_PATTERN,
- DUPLICATE_UNDERSCORE_ARGUMENT,
- REDUNDANT_CLOSURE_CALL,
- DOUBLE_NEG,
- MIXED_CASE_HEX_LITERALS,
- UNSEPARATED_LITERAL_SUFFIX,
- ZERO_PREFIXED_LITERAL,
- BUILTIN_TYPE_SHADOW
- )
- }
+declare_clippy_lint! {
+ /// **What it does:** Checks for patterns in the form `name @ _`.
+ ///
+ /// **Why is this bad?** It's almost always more readable to just use direct
+ /// bindings.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// # let v = Some("abc");
+ ///
+ /// match v {
+ /// Some(x) => (),
+ /// y @ _ => (), // easier written as `y`,
+ /// }
+ /// ```
+ pub REDUNDANT_PATTERN,
+ style,
+ "using `name @ _` in a pattern"
}
-// Used to find `return` statements or equivalents e.g. `?`
+declare_lint_pass!(MiscEarlyLints => [
+ UNNEEDED_FIELD_PATTERN,
+ DUPLICATE_UNDERSCORE_ARGUMENT,
+ REDUNDANT_CLOSURE_CALL,
+ DOUBLE_NEG,
+ MIXED_CASE_HEX_LITERALS,
+ UNSEPARATED_LITERAL_SUFFIX,
+ ZERO_PREFIXED_LITERAL,
+ BUILTIN_TYPE_SHADOW,
+ REDUNDANT_PATTERN
+]);
+
+// Used to find `return` statements or equivalents e.g., `?`
struct ReturnVisitor {
found_return: bool,
}
impl ReturnVisitor {
- fn new() -> ReturnVisitor {
- ReturnVisitor {
- found_return: false,
- }
+ fn new() -> Self {
+ Self { found_return: false }
}
}
}
}
-impl EarlyLintPass for MiscEarly {
+impl EarlyLintPass for MiscEarlyLints {
fn check_generics(&mut self, cx: &EarlyContext<'_>, gen: &Generics) {
for param in &gen.params {
if let GenericParamKind::Type { .. } = param.kind {
fn check_pat(&mut self, cx: &EarlyContext<'_>, pat: &Pat) {
if let PatKind::Struct(ref npat, ref pfields, _) = pat.node {
let mut wilds = 0;
- let type_name = npat.segments
+ let type_name = npat
+ .segments
.last()
.expect("A path must have at least one segment")
.ident
.name;
for field in pfields {
- if let PatKind::Wild = field.node.pat.node {
+ if let PatKind::Wild = field.pat.node {
wilds += 1;
}
}
let mut normal = vec![];
for field in pfields {
- match field.node.pat.node {
+ match field.pat.node {
PatKind::Wild => {},
- _ => if let Ok(n) = cx.sess().source_map().span_to_snippet(field.span) {
- normal.push(n);
+ _ => {
+ if let Ok(n) = cx.sess().source_map().span_to_snippet(field.span) {
+ normal.push(n);
+ }
},
}
}
for field in pfields {
- if let PatKind::Wild = field.node.pat.node {
+ if let PatKind::Wild = field.pat.node {
wilds -= 1;
if wilds > 0 {
span_lint(
}
}
}
+
+ if let PatKind::Ident(_, ident, Some(ref right)) = pat.node {
+ if let PatKind::Wild = right.node {
+ span_lint_and_sugg(
+ cx,
+ REDUNDANT_PATTERN,
+ pat.span,
+ &format!(
+ "the `{} @ _` pattern can be written as just `{}`",
+ ident.name, ident.name,
+ ),
+ "try",
+ format!("{}", ident.name),
+ Applicability::MachineApplicable,
+ );
+ }
+ }
}
fn check_fn(&mut self, cx: &EarlyContext<'_>, _: FnKind<'_>, decl: &FnDecl, _: Span, _: NodeId) {
name makes code comprehension and documentation more difficult",
arg_name[1..].to_owned()
),
- );;
+ );
}
} else {
registered_names.insert(arg_name, arg.pat.span);
return;
}
match expr.node {
- ExprKind::Call(ref paren, _) => if let ExprKind::Paren(ref closure) = paren.node {
- if let ExprKind::Closure(_, _, _, ref decl, ref block, _) = closure.node {
- let mut visitor = ReturnVisitor::new();
- visitor.visit_expr(block);
- if !visitor.found_return {
- span_lint_and_then(
- cx,
- REDUNDANT_CLOSURE_CALL,
- expr.span,
- "Try not to call a closure in the expression where it is declared.",
- |db| if decl.inputs.is_empty() {
- let hint = snippet(cx, block.span, "..").into_owned();
- db.span_suggestion_with_applicability(
- expr.span,
- "Try doing something like: ",
- hint,
- Applicability::MachineApplicable, // snippet
- );
- },
- );
+ ExprKind::Call(ref paren, _) => {
+ if let ExprKind::Paren(ref closure) = paren.node {
+ if let ExprKind::Closure(_, _, _, ref decl, ref block, _) = closure.node {
+ let mut visitor = ReturnVisitor::new();
+ visitor.visit_expr(block);
+ if !visitor.found_return {
+ span_lint_and_then(
+ cx,
+ REDUNDANT_CLOSURE_CALL,
+ expr.span,
+ "Try not to call a closure in the expression where it is declared.",
+ |db| {
+ if decl.inputs.is_empty() {
+ let hint = snippet(cx, block.span, "..").into_owned();
+ db.span_suggestion(
+ expr.span,
+ "Try doing something like: ",
+ hint,
+ Applicability::MachineApplicable, // snippet
+ );
+ }
+ },
+ );
+ }
}
}
},
- ExprKind::Unary(UnOp::Neg, ref inner) => if let ExprKind::Unary(UnOp::Neg, _) = inner.node {
- span_lint(
- cx,
- DOUBLE_NEG,
- expr.span,
- "`--x` could be misinterpreted as pre-decrement by C programmers, is usually a no-op",
- );
+ ExprKind::Unary(UnOp::Neg, ref inner) => {
+ if let ExprKind::Unary(UnOp::Neg, _) = inner.node {
+ span_lint(
+ cx,
+ DOUBLE_NEG,
+ expr.span,
+ "`--x` could be misinterpreted as pre-decrement by C programmers, is usually a no-op",
+ );
+ }
},
ExprKind::Lit(ref lit) => self.check_lit(cx, lit),
_ => (),
}
}
-impl MiscEarly {
+impl MiscEarlyLints {
fn check_lit(self, cx: &EarlyContext<'_>, lit: &Lit) {
- if_chain! {
- if let LitKind::Int(value, ..) = lit.node;
- if let Some(src) = snippet_opt(cx, lit.span);
- if let Some(firstch) = src.chars().next();
- if char::to_digit(firstch, 10).is_some();
- then {
- let mut prev = '\0';
- for ch in src.chars() {
- if ch == 'i' || ch == 'u' {
- if prev != '_' {
- span_lint(cx, UNSEPARATED_LITERAL_SUFFIX, lit.span,
- "integer type suffix should be separated by an underscore");
- }
- break;
- }
- prev = ch;
- }
- if src.starts_with("0x") {
- let mut seen = (false, false);
- for ch in src.chars() {
- match ch {
- 'a' ..= 'f' => seen.0 = true,
- 'A' ..= 'F' => seen.1 = true,
- 'i' | 'u' => break, // start of suffix already
- _ => ()
- }
+ // We test if first character in snippet is a number, because the snippet could be an expansion
+ // from a built-in macro like `line!()` or a proc-macro like `#[wasm_bindgen]`.
+ // Note that this check also covers special case that `line!()` is eagerly expanded by compiler.
+ // See <https://github.com/rust-lang/rust-clippy/issues/4507> for a regression.
+ // FIXME: Find a better way to detect those cases.
+ let lit_snip = match snippet_opt(cx, lit.span) {
+ Some(snip) if snip.chars().next().map_or(false, |c| c.is_digit(10)) => snip,
+ _ => return,
+ };
+
+ if let LitKind::Int(value, lit_int_type) = lit.node {
+ let suffix = match lit_int_type {
+ LitIntType::Signed(ty) => ty.ty_to_string(),
+ LitIntType::Unsigned(ty) => ty.ty_to_string(),
+ LitIntType::Unsuffixed => "",
+ };
+
+ let maybe_last_sep_idx = lit_snip.len() - suffix.len() - 1;
+ // Do not lint when literal is unsuffixed.
+ if !suffix.is_empty() && lit_snip.as_bytes()[maybe_last_sep_idx] != b'_' {
+ span_lint_and_sugg(
+ cx,
+ UNSEPARATED_LITERAL_SUFFIX,
+ lit.span,
+ "integer type suffix should be separated by an underscore",
+ "add an underscore",
+ format!("{}_{}", &lit_snip[..=maybe_last_sep_idx], suffix),
+ Applicability::MachineApplicable,
+ );
+ }
+
+ if lit_snip.starts_with("0x") {
+ let mut seen = (false, false);
+ for ch in lit_snip.as_bytes()[2..=maybe_last_sep_idx].iter() {
+ match ch {
+ b'a'..=b'f' => seen.0 = true,
+ b'A'..=b'F' => seen.1 = true,
+ _ => {},
}
if seen.0 && seen.1 {
- span_lint(cx, MIXED_CASE_HEX_LITERALS, lit.span,
- "inconsistent casing in hexadecimal literal");
+ span_lint(
+ cx,
+ MIXED_CASE_HEX_LITERALS,
+ lit.span,
+ "inconsistent casing in hexadecimal literal",
+ );
+ break;
}
- } else if src.starts_with("0b") || src.starts_with("0o") {
- /* nothing to do */
- } else if value != 0 && src.starts_with('0') {
- span_lint_and_then(cx,
- ZERO_PREFIXED_LITERAL,
- lit.span,
- "this is a decimal constant",
- |db| {
- db.span_suggestion_with_applicability(
+ }
+ } else if lit_snip.starts_with("0b") || lit_snip.starts_with("0o") {
+ /* nothing to do */
+ } else if value != 0 && lit_snip.starts_with('0') {
+ span_lint_and_then(
+ cx,
+ ZERO_PREFIXED_LITERAL,
+ lit.span,
+ "this is a decimal constant",
+ |db| {
+ db.span_suggestion(
lit.span,
- "if you mean to use a decimal constant, remove the `0` to remove confusion",
- src.trim_left_matches(|c| c == '_' || c == '0').to_string(),
+ "if you mean to use a decimal constant, remove the `0` to avoid confusion",
+ lit_snip.trim_start_matches(|c| c == '_' || c == '0').to_string(),
Applicability::MaybeIncorrect,
);
- db.span_suggestion_with_applicability(
+ db.span_suggestion(
lit.span,
"if you mean to use an octal constant, use `0o`",
- format!("0o{}", src.trim_left_matches(|c| c == '_' || c == '0')),
+ format!("0o{}", lit_snip.trim_start_matches(|c| c == '_' || c == '0')),
Applicability::MaybeIncorrect,
);
- });
- }
+ },
+ );
}
- }
- if_chain! {
- if let LitKind::Float(..) = lit.node;
- if let Some(src) = snippet_opt(cx, lit.span);
- if let Some(firstch) = src.chars().next();
- if char::to_digit(firstch, 10).is_some();
- then {
- let mut prev = '\0';
- for ch in src.chars() {
- if ch == 'f' {
- if prev != '_' {
- span_lint(cx, UNSEPARATED_LITERAL_SUFFIX, lit.span,
- "float type suffix should be separated by an underscore");
- }
- break;
- }
- prev = ch;
- }
+ } else if let LitKind::Float(_, float_ty) = lit.node {
+ let suffix = float_ty.ty_to_string();
+ let maybe_last_sep_idx = lit_snip.len() - suffix.len() - 1;
+ if lit_snip.as_bytes()[maybe_last_sep_idx] != b'_' {
+ span_lint_and_sugg(
+ cx,
+ UNSEPARATED_LITERAL_SUFFIX,
+ lit.span,
+ "float type suffix should be separated by an underscore",
+ "add an underscore",
+ format!("{}_{}", &lit_snip[..=maybe_last_sep_idx], suffix),
+ Applicability::MachineApplicable,
+ );
}
}
}
projects / rust.git / blobdiff