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Merge pull request #548 from mcarton/fixes

Browse source 
Fix #433 and doc
This commit is contained in:
Manish Goregaokar 2016-01-13 22:04:44 +05:30
commit f6f8723c78
7 changed files with 162 additions and 134 deletions
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1
Cargo.toml
View file

@ -29,5 +29,4 @@ rustc-serialize = "0.3"
[features]
structured_logging = []
debugging = []

2
README.md
View file

@ -32,7 +32,6 @@ name
[explicit_iter_loop](https://github.com/Manishearth/rust-clippy/wiki#explicit_iter_loop) | warn | for-looping over `_.iter()` or `_.iter_mut()` when `&_` or `&mut _` would do
[filter_next](https://github.com/Manishearth/rust-clippy/wiki#filter_next) | warn | using `filter(p).next()`, which is more succinctly expressed as `.find(p)`
[float_cmp](https://github.com/Manishearth/rust-clippy/wiki#float_cmp) | warn | using `==` or `!=` on float values (as floating-point operations usually involve rounding errors, it is always better to check for approximate equality within small bounds)
[hashmap_entry](https://github.com/Manishearth/rust-clippy/wiki#hashmap_entry) | warn | use of `contains_key` followed by `insert` on a `HashMap`
[identity_op](https://github.com/Manishearth/rust-clippy/wiki#identity_op) | warn | using identity operations, e.g. `x + 0` or `y / 1`
[ineffective_bit_mask](https://github.com/Manishearth/rust-clippy/wiki#ineffective_bit_mask) | warn | expressions where a bit mask will be rendered useless by a comparison, e.g. `(x | 1) > 2`
[inline_always](https://github.com/Manishearth/rust-clippy/wiki#inline_always) | warn | `#[inline(always)]` is a bad idea in most cases
@ -43,6 +42,7 @@ name
[let_unit_value](https://github.com/Manishearth/rust-clippy/wiki#let_unit_value) | warn | creating a let binding to a value of unit type, which usually can't be used afterwards
[linkedlist](https://github.com/Manishearth/rust-clippy/wiki#linkedlist) | warn | usage of LinkedList, usually a vector is faster, or a more specialized data structure like a VecDeque
[map_clone](https://github.com/Manishearth/rust-clippy/wiki#map_clone) | warn | using `.map(|x| x.clone())` to clone an iterator or option's contents (recommends `.cloned()` instead)
[map_entry](https://github.com/Manishearth/rust-clippy/wiki#map_entry) | warn | use of `contains_key` followed by `insert` on a `HashMap` or `BTreeMap`
[match_bool](https://github.com/Manishearth/rust-clippy/wiki#match_bool) | warn | a match on boolean expression; recommends `if..else` block instead
[match_overlapping_arm](https://github.com/Manishearth/rust-clippy/wiki#match_overlapping_arm) | warn | a match has overlapping arms
[match_ref_pats](https://github.com/Manishearth/rust-clippy/wiki#match_ref_pats) | warn | a match or `if let` has all arms prefixed with `&`; the match expression can be dereferenced instead

70
src/hashmap.rs → src/entry.rs
View file

@ -1,12 +1,13 @@
use rustc::lint::*;
use rustc_front::hir::*;
use syntax::codemap::Span;
use utils::{get_item_name, is_exp_equal, match_type, snippet, span_help_and_lint, walk_ptrs_ty};
use utils::HASHMAP_PATH;
use utils::{get_item_name, is_exp_equal, match_type, snippet, span_lint_and_then, walk_ptrs_ty};
use utils::{BTREEMAP_PATH, HASHMAP_PATH};
/// **What it does:** This lint checks for uses of `contains_key` + `insert` on `HashMap`.
/// **What it does:** This lint checks for uses of `contains_key` + `insert` on `HashMap` or
/// `BTreeMap`.
///
/// **Why is this bad?** Using `HashMap::entry` is more efficient.
/// **Why is this bad?** Using `entry` is more efficient.
///
/// **Known problems:** Some false negatives, eg.:
/// ```
@ -23,9 +24,9 @@ use utils::HASHMAP_PATH;
/// m.entry(k).or_insert(v);
/// ```
declare_lint! {
pub HASHMAP_ENTRY,
pub MAP_ENTRY,
Warn,
"use of `contains_key` followed by `insert` on a `HashMap`"
"use of `contains_key` followed by `insert` on a `HashMap` or `BTreeMap`"
}
#[derive(Copy,Clone)]
@ -33,7 +34,7 @@ pub struct HashMapLint;
impl LintPass for HashMapLint {
fn get_lints(&self) -> LintArray {
lint_array!(HASHMAP_ENTRY)
lint_array!(MAP_ENTRY)
}
}
@ -55,17 +56,25 @@ impl LateLintPass for HashMapLint {
let map = &params[0];
let obj_ty = walk_ptrs_ty(cx.tcx.expr_ty(map));
if match_type(cx, obj_ty, &HASHMAP_PATH) {
let sole_expr = if then.expr.is_some() { 1 } else { 0 } + then.stmts.len() == 1;
let kind = if match_type(cx, obj_ty, &BTREEMAP_PATH) {
"BTreeMap"
}
else if match_type(cx, obj_ty, &HASHMAP_PATH) {
"HashMap"
}
else {
return
};
if let Some(ref then) = then.expr {
check_for_insert(cx, expr.span, map, key, then, sole_expr);
}
let sole_expr = if then.expr.is_some() { 1 } else { 0 } + then.stmts.len() == 1;
for stmt in &then.stmts {
if let StmtSemi(ref stmt, _) = stmt.node {
check_for_insert(cx, expr.span, map, key, stmt, sole_expr);
}
if let Some(ref then) = then.expr {
check_for_insert(cx, expr.span, map, key, then, sole_expr, kind);
}
for stmt in &then.stmts {
if let StmtSemi(ref stmt, _) = stmt.node {
check_for_insert(cx, expr.span, map, key, stmt, sole_expr, kind);
}
}
}
@ -73,7 +82,7 @@ impl LateLintPass for HashMapLint {
}
}
fn check_for_insert(cx: &LateContext, span: Span, map: &Expr, key: &Expr, expr: &Expr, sole_expr: bool) {
fn check_for_insert(cx: &LateContext, span: Span, map: &Expr, key: &Expr, expr: &Expr, sole_expr: bool, kind: &str) {
if_let_chain! {
[
let ExprMethodCall(ref name, _, ref params) = expr.node,
@ -82,21 +91,22 @@ fn check_for_insert(cx: &LateContext, span: Span, map: &Expr, key: &Expr, expr:
get_item_name(cx, map) == get_item_name(cx, &*params[0]),
is_exp_equal(cx, key, &params[1])
], {
if sole_expr {
span_help_and_lint(cx, HASHMAP_ENTRY, span,
"usage of `contains_key` followed by `insert` on `HashMap`",
&format!("Consider using `{}.entry({}).or_insert({})`",
snippet(cx, map.span, ".."),
snippet(cx, params[1].span, ".."),
snippet(cx, params[2].span, "..")));
let help = if sole_expr {
format!("{}.entry({}).or_insert({})",
snippet(cx, map.span, ".."),
snippet(cx, params[1].span, ".."),
snippet(cx, params[2].span, ".."))
}
else {
span_help_and_lint(cx, HASHMAP_ENTRY, span,
"usage of `contains_key` followed by `insert` on `HashMap`",
&format!("Consider using `{}.entry({})`",
snippet(cx, map.span, ".."),
snippet(cx, params[1].span, "..")));
}
format!("{}.entry({})",
snippet(cx, map.span, ".."),
snippet(cx, params[1].span, ".."))
};
span_lint_and_then(cx, MAP_ENTRY, span,
&format!("usage of `contains_key` followed by `insert` on `{}`", kind), |db| {
db.span_suggestion(span, "Consider using", help.clone());
});
}
}
}

6
src/lib.rs
View file

@ -71,7 +71,7 @@ pub mod temporary_assignment;
pub mod transmute;
pub mod cyclomatic_complexity;
pub mod escape;
pub mod hashmap;
pub mod entry;
pub mod misc_early;
pub mod array_indexing;
pub mod panic;
@ -113,7 +113,7 @@ pub fn plugin_registrar(reg: &mut Registry) {
reg.register_late_lint_pass(box types::UnitCmp);
reg.register_late_lint_pass(box loops::LoopsPass);
reg.register_late_lint_pass(box lifetimes::LifetimePass);
reg.register_late_lint_pass(box hashmap::HashMapLint);
reg.register_late_lint_pass(box entry::HashMapLint);
reg.register_late_lint_pass(box ranges::StepByZero);
reg.register_late_lint_pass(box types::CastPass);
reg.register_late_lint_pass(box types::TypeComplexityPass);
@ -167,10 +167,10 @@ pub fn plugin_registrar(reg: &mut Registry) {
block_in_if_condition::BLOCK_IN_IF_CONDITION_STMT,
collapsible_if::COLLAPSIBLE_IF,
cyclomatic_complexity::CYCLOMATIC_COMPLEXITY,
entry::MAP_ENTRY,
eq_op::EQ_OP,
escape::BOXED_LOCAL,
eta_reduction::REDUNDANT_CLOSURE,
hashmap::HASHMAP_ENTRY,
identity_op::IDENTITY_OP,
len_zero::LEN_WITHOUT_IS_EMPTY,
len_zero::LEN_ZERO,

124
src/utils.rs
View file

@ -19,17 +19,18 @@ use std::ops::{Deref, DerefMut};
pub type MethodArgs = HirVec<P<Expr>>;
// module DefPaths for certain structs/enums we check for
pub const BEGIN_UNWIND: [&'static str; 3] = ["std", "rt", "begin_unwind"];
pub const BTREEMAP_PATH: [&'static str; 4] = ["collections", "btree", "map", "BTreeMap"];
pub const CLONE_PATH: [&'static str; 2] = ["Clone", "clone"];
pub const COW_PATH: [&'static str; 3] = ["collections", "borrow", "Cow"];
pub const HASHMAP_PATH: [&'static str; 5] = ["std", "collections", "hash", "map", "HashMap"];
pub const LL_PATH: [&'static str; 3] = ["collections", "linked_list", "LinkedList"];
pub const MUTEX_PATH: [&'static str; 4] = ["std", "sync", "mutex", "Mutex"];
pub const OPEN_OPTIONS_PATH: [&'static str; 3] = ["std", "fs", "OpenOptions"];
pub const OPTION_PATH: [&'static str; 3] = ["core", "option", "Option"];
pub const RESULT_PATH: [&'static str; 3] = ["core", "result", "Result"];
pub const STRING_PATH: [&'static str; 3] = ["collections", "string", "String"];
pub const VEC_PATH: [&'static str; 3] = ["collections", "vec", "Vec"];
pub const LL_PATH: [&'static str; 3] = ["collections", "linked_list", "LinkedList"];
pub const HASHMAP_PATH: [&'static str; 5] = ["std", "collections", "hash", "map", "HashMap"];
pub const OPEN_OPTIONS_PATH: [&'static str; 3] = ["std", "fs", "OpenOptions"];
pub const MUTEX_PATH: [&'static str; 4] = ["std", "sync", "mutex", "Mutex"];
pub const CLONE_PATH: [&'static str; 2] = ["Clone", "clone"];
pub const BEGIN_UNWIND: [&'static str; 3] = ["std", "rt", "begin_unwind"];
pub const COW_PATH: [&'static str; 3] = ["collections", "borrow", "Cow"];
/// Produce a nested chain of if-lets and ifs from the patterns:
///
@ -77,20 +78,21 @@ macro_rules! if_let_chain {
};
}
/// Returns true if the two spans come from differing expansions (i.e. one is from a macro and one isn't)
/// Returns true if the two spans come from differing expansions (i.e. one is from a macro and one
/// isn't).
pub fn differing_macro_contexts(sp1: Span, sp2: Span) -> bool {
sp1.expn_id != sp2.expn_id
}
/// returns true if this expn_info was expanded by any macro
/// Returns true if this `expn_info` was expanded by any macro.
pub fn in_macro<T: LintContext>(cx: &T, span: Span) -> bool {
cx.sess().codemap().with_expn_info(span.expn_id, |info| info.is_some())
}
/// returns true if the macro that expanded the crate was outside of
/// the current crate or was a compiler plugin
/// Returns true if the macro that expanded the crate was outside of the current crate or was a
/// compiler plugin.
pub fn in_external_macro<T: LintContext>(cx: &T, span: Span) -> bool {
/// invokes in_macro with the expansion info of the given span
/// slightly heavy, try to use this after other checks have already happened
/// Invokes in_macro with the expansion info of the given span slightly heavy, try to use this
/// after other checks have already happened.
fn in_macro_ext<T: LintContext>(cx: &T, opt_info: Option<&ExpnInfo>) -> bool {
// no ExpnInfo = no macro
opt_info.map_or(false, |info| {
@ -109,9 +111,12 @@ pub fn in_external_macro<T: LintContext>(cx: &T, span: Span) -> bool {
cx.sess().codemap().with_expn_info(span.expn_id, |info| in_macro_ext(cx, info))
}
/// check if a DefId's path matches the given absolute type path
/// usage e.g. with
/// `match_def_path(cx, id, &["core", "option", "Option"])`
/// Check if a `DefId`'s path matches the given absolute type path usage.
///
/// # Examples
/// ```
/// match_def_path(cx, id, &["core", "option", "Option"])
/// ```
pub fn match_def_path(cx: &LateContext, def_id: DefId, path: &[&str]) -> bool {
cx.tcx.with_path(def_id, |iter| {
iter.zip(path)
@ -119,7 +124,7 @@ pub fn match_def_path(cx: &LateContext, def_id: DefId, path: &[&str]) -> bool {
})
}
/// check if type is struct or enum type with given def path
/// Check if type is struct or enum type with given def path.
pub fn match_type(cx: &LateContext, ty: ty::Ty, path: &[&str]) -> bool {
match ty.sty {
ty::TyEnum(ref adt, _) | ty::TyStruct(ref adt, _) => match_def_path(cx, adt.did, path),
@ -127,7 +132,7 @@ pub fn match_type(cx: &LateContext, ty: ty::Ty, path: &[&str]) -> bool {
}
}
/// check if method call given in "expr" belongs to given trait
/// Check if the method call given in `expr` belongs to given trait.
pub fn match_impl_method(cx: &LateContext, expr: &Expr, path: &[&str]) -> bool {
let method_call = ty::MethodCall::expr(expr.id);
@ -144,9 +149,10 @@ pub fn match_impl_method(cx: &LateContext, expr: &Expr, path: &[&str]) -> bool {
}
}
/// check if method call given in "expr" belongs to given trait
/// Check if the method call given in `expr` belongs to given trait.
pub fn match_trait_method(cx: &LateContext, expr: &Expr, path: &[&str]) -> bool {
let method_call = ty::MethodCall::expr(expr.id);
let trt_id = cx.tcx
.tables
.borrow()
@ -160,21 +166,31 @@ pub fn match_trait_method(cx: &LateContext, expr: &Expr, path: &[&str]) -> bool
}
}
/// match a Path against a slice of segment string literals, e.g.
/// `match_path(path, &["std", "rt", "begin_unwind"])`
/// Match a `Path` against a slice of segment string literals.
///
/// # Examples
/// ```
/// match_path(path, &["std", "rt", "begin_unwind"])
/// ```
pub fn match_path(path: &Path, segments: &[&str]) -> bool {
path.segments.iter().rev().zip(segments.iter().rev()).all(|(a, b)| a.identifier.name.as_str() == *b)
}
/// match a Path against a slice of segment string literals, e.g.
/// `match_path(path, &["std", "rt", "begin_unwind"])`
/// Match a `Path` against a slice of segment string literals, e.g.
///
/// # Examples
/// ```
/// match_path(path, &["std", "rt", "begin_unwind"])
/// ```
pub fn match_path_ast(path: &ast::Path, segments: &[&str]) -> bool {
path.segments.iter().rev().zip(segments.iter().rev()).all(|(a, b)| a.identifier.name.as_str() == *b)
}
/// match an Expr against a chain of methods, and return the matched Exprs. For example, if `expr`
/// represents the `.baz()` in `foo.bar().baz()`, `matched_method_chain(expr, &["bar", "baz"])`
/// will return a Vec containing the Exprs for `.bar()` and `.baz()`
/// Match an `Expr` against a chain of methods, and return the matched `Expr`s.
///
/// For example, if `expr` represents the `.baz()` in `foo.bar().baz()`,
/// `matched_method_chain(expr, &["bar", "baz"])` will return a `Vec` containing the `Expr`s for
/// `.bar()` and `.baz()`
pub fn method_chain_args<'a>(expr: &'a Expr, methods: &[&str]) -> Option<Vec<&'a MethodArgs>> {
let mut current = expr;
let mut matched = Vec::with_capacity(methods.len());
@ -196,7 +212,7 @@ pub fn method_chain_args<'a>(expr: &'a Expr, methods: &[&str]) -> Option<Vec<&'a
}
/// get the name of the item the expression is in, if available
/// Get the name of the item the expression is in, if available.
pub fn get_item_name(cx: &LateContext, expr: &Expr) -> Option<Name> {
let parent_id = cx.tcx.map.get_parent(expr.id);
match cx.tcx.map.find(parent_id) {
@ -207,7 +223,7 @@ pub fn get_item_name(cx: &LateContext, expr: &Expr) -> Option<Name> {
}
}
/// checks if a `let` decl is from a for loop desugaring
/// Checks if a `let` decl is from a `for` loop desugaring.
pub fn is_from_for_desugar(decl: &Decl) -> bool {
if_let_chain! {
[
@ -221,31 +237,39 @@ pub fn is_from_for_desugar(decl: &Decl) -> bool {
}
/// convert a span to a code snippet if available, otherwise use default, e.g.
/// `snippet(cx, expr.span, "..")`
/// Convert a span to a code snippet if available, otherwise use default.
///
/// # Example
/// ```
/// snippet(cx, expr.span, "..")
/// ```
pub fn snippet<'a, T: LintContext>(cx: &T, span: Span, default: &'a str) -> Cow<'a, str> {
cx.sess().codemap().span_to_snippet(span).map(From::from).unwrap_or(Cow::Borrowed(default))
}
/// Converts a span to a code snippet. Returns None if not available.
/// Convert a span to a code snippet. Returns `None` if not available.
pub fn snippet_opt<T: LintContext>(cx: &T, span: Span) -> Option<String> {
cx.sess().codemap().span_to_snippet(span).ok()
}
/// convert a span (from a block) to a code snippet if available, otherwise use default, e.g.
/// `snippet(cx, expr.span, "..")`
/// This trims the code of indentation, except for the first line
/// Use it for blocks or block-like things which need to be printed as such
/// Convert a span (from a block) to a code snippet if available, otherwise use default.
/// This trims the code of indentation, except for the first line. Use it for blocks or block-like
/// things which need to be printed as such.
///
/// # Example
/// ```
/// snippet(cx, expr.span, "..")
/// ```
pub fn snippet_block<'a, T: LintContext>(cx: &T, span: Span, default: &'a str) -> Cow<'a, str> {
let snip = snippet(cx, span, default);
trim_multiline(snip, true)
}
/// Like snippet_block, but add braces if the expr is not an ExprBlock
/// Also takes an Option<String> which can be put inside the braces
/// Like `snippet_block`, but add braces if the expr is not an `ExprBlock`.
/// Also takes an `Option<String>` which can be put inside the braces.
pub fn expr_block<'a, T: LintContext>(cx: &T, expr: &Expr, option: Option<String>, default: &'a str) -> Cow<'a, str> {
let code = snippet_block(cx, expr.span, default);
let string = option.map_or("".to_owned(), |s| s);
let string = option.unwrap_or_default();
if let ExprBlock(_) = expr.node {
Cow::Owned(format!("{}{}", code, string))
} else if string.is_empty() {
@ -255,8 +279,7 @@ pub fn expr_block<'a, T: LintContext>(cx: &T, expr: &Expr, option: Option<String
}
}
/// Trim indentation from a multiline string
/// with possibility of ignoring the first line
/// Trim indentation from a multiline string with possibility of ignoring the first line.
pub fn trim_multiline(s: Cow<str>, ignore_first: bool) -> Cow<str> {
let s_space = trim_multiline_inner(s, ignore_first, ' ');
let s_tab = trim_multiline_inner(s_space, ignore_first, '\t');
@ -296,7 +319,7 @@ fn trim_multiline_inner(s: Cow<str>, ignore_first: bool, ch: char) -> Cow<str> {
}
}
/// get a parent expr if any – this is useful to constrain a lint
/// Get a parent expressions if any – this is useful to constrain a lint.
pub fn get_parent_expr<'c>(cx: &'c LateContext, e: &Expr) -> Option<&'c Expr> {
let map = &cx.tcx.map;
let node_id: NodeId = e.id;
@ -349,7 +372,6 @@ impl<'a> Deref for DiagnosticWrapper<'a> {
}
}
#[cfg(not(feature="structured_logging"))]
pub fn span_lint<'a, T: LintContext>(cx: &'a T, lint: &'static Lint, sp: Span, msg: &str) -> DiagnosticWrapper<'a> {
let mut db = cx.struct_span_lint(lint, sp, msg);
if cx.current_level(lint) != Level::Allow {
@ -360,20 +382,6 @@ pub fn span_lint<'a, T: LintContext>(cx: &'a T, lint: &'static Lint, sp: Span, m
DiagnosticWrapper(db)
}
#[cfg(feature="structured_logging")]
pub fn span_lint<'a, T: LintContext>(cx: &'a T, lint: &'static Lint, sp: Span, msg: &str) -> DiagnosticWrapper<'a> {
// lint.name / lint.desc is can give details of the lint
// cx.sess().codemap() has all these nice functions for line/column/snippet details
// http://doc.rust-lang.org/syntax/codemap/struct.CodeMap.html#method.span_to_string
let mut db = cx.struct_span_lint(lint, sp, msg);
if cx.current_level(lint) != Level::Allow {
db.fileline_help(sp,
&format!("for further information visit https://github.com/Manishearth/rust-clippy/wiki#{}",
lint.name_lower()));
}
DiagnosticWrapper(db)
}
pub fn span_help_and_lint<'a, T: LintContext>(cx: &'a T, lint: &'static Lint, span: Span, msg: &str, help: &str)
-> DiagnosticWrapper<'a> {
let mut db = cx.struct_span_lint(lint, span, msg);
@ -418,7 +426,7 @@ pub fn span_lint_and_then<'a, T: LintContext, F>(cx: &'a T, lint: &'static Lint,
db
}
/// return the base type for references and raw pointers
/// Return the base type for references and raw pointers.
pub fn walk_ptrs_ty(ty: ty::Ty) -> ty::Ty {
match ty.sty {
ty::TyRef(_, ref tm) | ty::TyRawPtr(ref tm) => walk_ptrs_ty(tm.ty),
@ -426,7 +434,7 @@ pub fn walk_ptrs_ty(ty: ty::Ty) -> ty::Ty {
}
}
/// return the base type for references and raw pointers, and count reference depth
/// Return the base type for references and raw pointers, and count reference depth.
pub fn walk_ptrs_ty_depth(ty: ty::Ty) -> (ty::Ty, usize) {
fn inner(ty: ty::Ty, depth: usize) -> (ty::Ty, usize) {
match ty.sty {

52
tests/compile-fail/entry.rs Normal file
View file

@ -0,0 +1,52 @@
#![feature(plugin)]
#![plugin(clippy)]
#![allow(unused)]
#![deny(map_entry)]
use std::collections::{BTreeMap, HashMap};
use std::hash::Hash;
fn foo() {}
fn insert_if_absent0<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { m.insert(k, v); }
//~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
//~| HELP Consider
//~| SUGGESTION m.entry(k).or_insert(v)
}
fn insert_if_absent1<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { foo(); m.insert(k, v); }
//~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
//~| HELP Consider
//~| SUGGESTION m.entry(k)
}
fn insert_if_absent2<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { m.insert(k, v) } else { None };
//~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
//~| HELP Consider
//~| SUGGESTION m.entry(k).or_insert(v)
}
fn insert_if_absent3<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
//~^ ERROR usage of `contains_key` followed by `insert` on `HashMap`
//~| HELP Consider
//~| SUGGESTION m.entry(k)
}
fn insert_in_btreemap<K: Ord, V>(m: &mut BTreeMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
//~^ ERROR usage of `contains_key` followed by `insert` on `BTreeMap`
//~| HELP Consider
//~| SUGGESTION m.entry(k)
}
fn insert_other_if_absent<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, o: K, v: V) {
if !m.contains_key(&k) { m.insert(o, v); }
}
fn main() {
}

41
tests/compile-fail/hashmap.rs
View file

@ -1,41 +0,0 @@
#![feature(plugin)]
#![plugin(clippy)]
#![allow(unused)]
#![deny(hashmap_entry)]
use std::collections::HashMap;
use std::hash::Hash;
fn foo() {}
fn insert_if_absent0<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { m.insert(k, v); }
//~^ERROR: usage of `contains_key` followed by `insert` on `HashMap`
//~^^HELP: Consider using `m.entry(k).or_insert(v)`
}
fn insert_if_absent1<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { foo(); m.insert(k, v); }
//~^ERROR: usage of `contains_key` followed by `insert` on `HashMap`
//~^^HELP: Consider using `m.entry(k)`
}
fn insert_if_absent2<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { m.insert(k, v) } else { None };
//~^ERROR: usage of `contains_key` followed by `insert` on `HashMap`
//~^^HELP: Consider using `m.entry(k).or_insert(v)`
}
fn insert_if_absent3<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, v: V) {
if !m.contains_key(&k) { foo(); m.insert(k, v) } else { None };
//~^ERROR: usage of `contains_key` followed by `insert` on `HashMap`
//~^^HELP: Consider using `m.entry(k)`
}
fn insert_other_if_absent<K: Eq + Hash, V>(m: &mut HashMap<K, V>, k: K, o: K, v: V) {
if !m.contains_key(&k) { m.insert(o, v); }
}
fn main() {
}