Merge pull request #565 from mcarton/or_fun_call

Handle Entry types in OR_FUN_CALL lint
This commit is contained in:
llogiq 2016-01-20 12:31:54 +01:00
commit fdcd9743ee
3 changed files with 45 additions and 13 deletions

View file

@ -9,7 +9,10 @@ use syntax::codemap::Span;
use utils::{snippet, span_lint, span_note_and_lint, match_path, match_type, method_chain_args, match_trait_method,
walk_ptrs_ty_depth, walk_ptrs_ty, get_trait_def_id, implements_trait};
use utils::{DEFAULT_TRAIT_PATH, OPTION_PATH, RESULT_PATH, STRING_PATH};
use utils::{
BTREEMAP_ENTRY_PATH, DEFAULT_TRAIT_PATH, HASHMAP_ENTRY_PATH, OPTION_PATH,
RESULT_PATH, STRING_PATH
};
use utils::MethodArgs;
use rustc::middle::cstore::CrateStore;
@ -343,19 +346,31 @@ fn lint_or_fun_call(cx: &LateContext, expr: &Expr, name: &str, args: &[P<Expr>])
or_has_args: bool,
span: Span
) {
// (path, fn_has_argument, methods)
let know_types : &[(&[_], _, &[_], _)] = &[
(&BTREEMAP_ENTRY_PATH, false, &["or_insert"], "with"),
(&HASHMAP_ENTRY_PATH, false, &["or_insert"], "with"),
(&OPTION_PATH, false, &["map_or", "ok_or", "or", "unwrap_or"], "else"),
(&RESULT_PATH, true, &["or", "unwrap_or"], "else"),
];
let self_ty = cx.tcx.expr_ty(self_expr);
let is_result = if match_type(cx, self_ty, &RESULT_PATH) {
true
}
else if match_type(cx, self_ty, &OPTION_PATH) {
false
let (fn_has_arguments, poss, suffix) =
if let Some(&(_, fn_has_arguments, poss, suffix)) = know_types.iter().find(|&&i| {
match_type(cx, self_ty, i.0)
}) {
(fn_has_arguments, poss, suffix)
}
else {
return;
return
};
let sugg = match (is_result, !or_has_args) {
if !poss.contains(&name) {
return
}
let sugg = match (fn_has_arguments, !or_has_args) {
(true, _) => format!("|_| {}", snippet(cx, arg.span, "..")),
(false, false) => format!("|| {}", snippet(cx, arg.span, "..")),
(false, true) => format!("{}", snippet(cx, fun.span, "..")),
@ -364,13 +379,14 @@ fn lint_or_fun_call(cx: &LateContext, expr: &Expr, name: &str, args: &[P<Expr>])
span_lint(cx, OR_FUN_CALL, span,
&format!("use of `{}` followed by a function call", name))
.span_suggestion(span, "try this",
format!("{}.{}_else({})",
format!("{}.{}_{}({})",
snippet(cx, self_expr.span, "_"),
name,
suffix,
sugg));
}
if args.len() == 2 && ["map_or", "ok_or", "or", "unwrap_or"].contains(&name) {
if args.len() == 2 {
if let ExprCall(ref fun, ref or_args) = args[1].node {
let or_has_args = !or_args.is_empty();
if !check_unwrap_or_default(cx, name, fun, &args[0], &args[1], or_has_args, expr.span) {

View file

@ -20,10 +20,12 @@ 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_ENTRY_PATH: [&'static str; 4] = ["collections", "btree", "map", "Entry"];
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 DEFAULT_TRAIT_PATH: [&'static str; 3] = ["core", "default", "Default"];
pub const HASHMAP_ENTRY_PATH: [&'static str; 5] = ["std", "collections", "hash", "map", "Entry"];
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"];

View file

@ -4,6 +4,8 @@
#![allow(unused)]
#![deny(clippy, clippy_pedantic)]
use std::collections::BTreeMap;
use std::collections::HashMap;
use std::ops::Mul;
struct T;
@ -238,6 +240,18 @@ fn or_fun_call() {
//~^ERROR use of `unwrap_or`
//~|HELP try this
//~|SUGGESTION without_default.unwrap_or_else(Foo::new);
let mut map = HashMap::<u64, String>::new();
map.entry(42).or_insert(String::new());
//~^ERROR use of `or_insert` followed by a function call
//~|HELP try this
//~|SUGGESTION map.entry(42).or_insert_with(String::new);
let mut btree = BTreeMap::<u64, String>::new();
btree.entry(42).or_insert(String::new());
//~^ERROR use of `or_insert` followed by a function call
//~|HELP try this
//~|SUGGESTION btree.entry(42).or_insert_with(String::new);
}
fn main() {