rust/clippy_lints/src/missing_enforced_import_rename.rs

107 lines
3.6 KiB
Rust

use clippy_config::types::Rename;
use clippy_utils::diagnostics::span_lint_and_sugg;
use clippy_utils::source::snippet_opt;
use rustc_data_structures::fx::FxHashMap;
use rustc_errors::Applicability;
use rustc_hir::def::Res;
use rustc_hir::def_id::DefId;
use rustc_hir::{Item, ItemKind, UseKind};
use rustc_lint::{LateContext, LateLintPass, LintContext};
use rustc_session::impl_lint_pass;
use rustc_span::Symbol;
declare_clippy_lint! {
/// ### What it does
/// Checks for imports that do not rename the item as specified
/// in the `enforced-import-renames` config option.
///
/// Note: Even though this lint is warn-by-default, it will only trigger if
/// import renames are defined in the `clippy.toml` file.
///
/// ### Why is this bad?
/// Consistency is important; if a project has defined import renames, then they should be
/// followed. More practically, some item names are too vague outside of their defining scope,
/// in which case this can enforce a more meaningful naming.
///
/// ### Example
/// An example clippy.toml configuration:
/// ```toml
/// # clippy.toml
/// enforced-import-renames = [
/// { path = "serde_json::Value", rename = "JsonValue" },
/// ]
/// ```
///
/// ```rust,ignore
/// use serde_json::Value;
/// ```
/// Use instead:
/// ```rust,ignore
/// use serde_json::Value as JsonValue;
/// ```
#[clippy::version = "1.55.0"]
pub MISSING_ENFORCED_IMPORT_RENAMES,
style,
"enforce import renames"
}
pub struct ImportRename {
conf_renames: Vec<Rename>,
renames: FxHashMap<DefId, Symbol>,
}
impl ImportRename {
pub fn new(conf_renames: Vec<Rename>) -> Self {
Self {
conf_renames,
renames: FxHashMap::default(),
}
}
}
impl_lint_pass!(ImportRename => [MISSING_ENFORCED_IMPORT_RENAMES]);
impl LateLintPass<'_> for ImportRename {
fn check_crate(&mut self, cx: &LateContext<'_>) {
for Rename { path, rename } in &self.conf_renames {
let segs = path.split("::").collect::<Vec<_>>();
for id in clippy_utils::def_path_def_ids(cx, &segs) {
self.renames.insert(id, Symbol::intern(rename));
}
}
}
fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
if let ItemKind::Use(path, UseKind::Single) = &item.kind {
for &res in &path.res {
if let Res::Def(_, id) = res
&& let Some(name) = self.renames.get(&id)
// Remove semicolon since it is not present for nested imports
&& let span_without_semi = cx.sess().source_map().span_until_char(item.span, ';')
&& let Some(snip) = snippet_opt(cx, span_without_semi)
&& let Some(import) = match snip.split_once(" as ") {
None => Some(snip.as_str()),
Some((import, rename)) => {
if rename.trim() == name.as_str() {
None
} else {
Some(import.trim())
}
},
}
{
span_lint_and_sugg(
cx,
MISSING_ENFORCED_IMPORT_RENAMES,
span_without_semi,
"this import should be renamed",
"try",
format!("{import} as {name}",),
Applicability::MachineApplicable,
);
}
}
}
}
}