Auto merge of rust-lang#7300 - DevinR528:import-rename, r=camsteffen

Add import_rename lint, this adds a field on the Conf struct

fixes rust-lang#7276

changelog: Add ``[`import_rename`]`` a lint that enforces import renaming defined in the config file.

Author: bors

CHANGELOG.md

@@ -2657,6 +2657,7 @@ Released 2018-09-13
 [`misrefactored_assign_op`]: https://rust-lang.github.io/rust-clippy/master/index.html#misrefactored_assign_op
 [`missing_const_for_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_const_for_fn
 [`missing_docs_in_private_items`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_docs_in_private_items
+[`missing_enforced_import_renames`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_enforced_import_renames
 [`missing_errors_doc`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_errors_doc
 [`missing_inline_in_public_items`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_inline_in_public_items
 [`missing_panics_doc`]: https://rust-lang.github.io/rust-clippy/master/index.html#missing_panics_doc

clippy_lints/src/lib.rs

@@ -267,6 +267,7 @@ mod misc;
 mod misc_early;
 mod missing_const_for_fn;
 mod missing_doc;
+mod missing_enforced_import_rename;
 mod missing_inline;
 mod modulo_arithmetic;
 mod multiple_crate_versions;
@@ -813,6 +814,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         misc_early::ZERO_PREFIXED_LITERAL,
         missing_const_for_fn::MISSING_CONST_FOR_FN,
         missing_doc::MISSING_DOCS_IN_PRIVATE_ITEMS,
+        missing_enforced_import_rename::MISSING_ENFORCED_IMPORT_RENAMES,
         missing_inline::MISSING_INLINE_IN_PUBLIC_ITEMS,
         modulo_arithmetic::MODULO_ARITHMETIC,
         multiple_crate_versions::MULTIPLE_CRATE_VERSIONS,
@@ -1017,6 +1019,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(misc::FLOAT_CMP_CONST),
         LintId::of(misc_early::UNNEEDED_FIELD_PATTERN),
         LintId::of(missing_doc::MISSING_DOCS_IN_PRIVATE_ITEMS),
+        LintId::of(missing_enforced_import_rename::MISSING_ENFORCED_IMPORT_RENAMES),
         LintId::of(missing_inline::MISSING_INLINE_IN_PUBLIC_ITEMS),
         LintId::of(modulo_arithmetic::MODULO_ARITHMETIC),
         LintId::of(panic_in_result_fn::PANIC_IN_RESULT_FN),
@@ -2077,6 +2080,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| box unused_async::UnusedAsync);
     let disallowed_types = conf.disallowed_types.iter().cloned().collect::<FxHashSet<_>>();
     store.register_late_pass(move || box disallowed_type::DisallowedType::new(&disallowed_types));
+    let import_renames = conf.enforced_import_renames.clone();
+    store.register_late_pass(move || box missing_enforced_import_rename::ImportRename::new(import_renames.clone()));
 
 }
 

clippy_lints/src/missing_enforced_import_rename.rs

@@ -0,0 +1,102 @@
+use clippy_utils::{diagnostics::span_lint_and_sugg, source::snippet_opt};
+
+use rustc_data_structures::fx::FxHashMap;
+use rustc_errors::Applicability;
+use rustc_hir::{def::Res, def_id::DefId, Crate, Item, ItemKind, UseKind};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::Symbol;
+
+use crate::utils::conf::Rename;
+
+declare_clippy_lint! {
+    /// **What it does:** Checks for imports that do not rename the item as specified
+    /// in the `enforce-import-renames` config option.
+    ///
+    /// **Why is this bad?** Consistency is important, if a project has defined import
+    /// renames they should be followed. More practically, some item names are too
+    /// vague outside of their defining scope this can enforce a more meaningful naming.
+    ///
+    /// **Known problems:** None
+    ///
+    /// **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;
+    /// ```
+    pub MISSING_ENFORCED_IMPORT_RENAMES,
+    restriction,
+    "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<'_>, _: &Crate<'_>) {
+        for Rename { path, rename } in &self.conf_renames {
+            if let Res::Def(_, id) = clippy_utils::path_to_res(cx, &path.split("::").collect::<Vec<_>>()) {
+                self.renames.insert(id, Symbol::intern(rename));
+            }
+        }
+    }
+
+    fn check_item(&mut self, cx: &LateContext<'_>, item: &Item<'_>) {
+        if_chain! {
+            if let ItemKind::Use(path, UseKind::Single) = &item.kind;
+            if let Res::Def(_, id) = path.res;
+            if 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, ';');
+            if let Some(snip) = snippet_opt(cx, span_without_semi);
+            if 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())
+                    }
+                },
+            };
+            then {
+                span_lint_and_sugg(
+                    cx,
+                    MISSING_ENFORCED_IMPORT_RENAMES,
+                    span_without_semi,
+                    "this import should be renamed",
+                    "try",
+                    format!(
+                        "{} as {}",
+                        import,
+                        name,
+                    ),
+                    Applicability::MachineApplicable,
+                );
+            }
+        }
+    }
+}

clippy_lints/src/utils/conf.rs

@@ -8,6 +8,13 @@ use std::error::Error;
 use std::path::{Path, PathBuf};
 use std::{env, fmt, fs, io};
 
+/// Holds information used by `MISSING_ENFORCED_IMPORT_RENAMES` lint.
+#[derive(Clone, Debug, Deserialize)]
+pub struct Rename {
+    pub path: String,
+    pub rename: String,
+}
+
 /// Conf with parse errors
 #[derive(Default)]
 pub struct TryConf {
@@ -203,6 +210,8 @@ define_Conf! {
     (cargo_ignore_publish: bool = false),
     /// Lint: NONSTANDARD_MACRO_BRACES. Enforce the named macros always use the braces specified. <br> A `MacroMatcher` can be added like so `{ name = "macro_name", brace = "(" }`. If the macro is could be used with a full path two `MacroMatcher`s have to be added one with the full path `crate_name::macro_name` and one with just the macro name.
     (standard_macro_braces: Vec<crate::nonstandard_macro_braces::MacroMatcher> = Vec::new()),
+    /// Lint: MISSING_ENFORCED_IMPORT_RENAMES. The list of imports to always rename, a fully qualified path followed by the rename.
+    (enforced_import_renames: Vec<crate::utils::conf::Rename> = Vec::new()),
 }
 
 /// Search for the configuration file.

tests/ui-toml/missing_enforced_import_rename/clippy.toml

@@ -0,0 +1,10 @@
+enforced-import-renames = [
+    { path = "std::option::Option", rename = "Maybe" },
+    { path = "std::process::Child", rename = "Kid" },
+    { path = "std::process::exit", rename = "goodbye" },
+    { path = "std::collections::BTreeMap", rename = "Map" },
+    { path = "std::clone", rename = "foo" },
+    { path = "std::thread::sleep", rename = "thread_sleep" },
+    { path = "std::any::type_name", rename = "ident" },
+    { path = "std::sync::Mutex", rename = "StdMutie" }
+]

tests/ui-toml/missing_enforced_import_rename/conf_missing_enforced_import_rename.rs

@@ -0,0 +1,16 @@
+#![warn(clippy::missing_enforced_import_renames)]
+
+use std::alloc as colla;
+use std::option::Option as Maybe;
+use std::process::{exit as wrong_exit, Child as Kid};
+use std::thread::sleep;
+#[rustfmt::skip]
+use std::{
+    any::{type_name, Any},
+    clone,
+    sync :: Mutex,
+};
+
+fn main() {
+    use std::collections::BTreeMap as OopsWrongRename;
+}

tests/ui-toml/missing_enforced_import_rename/conf_missing_enforced_import_rename.stderr

@@ -0,0 +1,40 @@
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:5:20
+   |
+LL | use std::process::{exit as wrong_exit, Child as Kid};
+   |                    ^^^^^^^^^^^^^^^^^^ help: try: `exit as goodbye`
+   |
+   = note: `-D clippy::missing-enforced-import-renames` implied by `-D warnings`
+
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:6:1
+   |
+LL | use std::thread::sleep;
+   | ^^^^^^^^^^^^^^^^^^^^^^ help: try: `use std::thread::sleep as thread_sleep`
+
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:9:11
+   |
+LL |     any::{type_name, Any},
+   |           ^^^^^^^^^ help: try: `type_name as ident`
+
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:10:5
+   |
+LL |     clone,
+   |     ^^^^^ help: try: `clone as foo`
+
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:11:5
+   |
+LL |     sync :: Mutex,
+   |     ^^^^^^^^^^^^^ help: try: `sync :: Mutex as StdMutie`
+
+error: this import should be renamed
+  --> $DIR/conf_missing_enforced_import_rename.rs:15:5
+   |
+LL |     use std::collections::BTreeMap as OopsWrongRename;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `use std::collections::BTreeMap as Map`
+
+error: aborting due to 6 previous errors
+

tests/ui-toml/toml_unknown_key/conf_unknown_key.stderr

@@ -1,4 +1,4 @@
-error: error reading Clippy's configuration file `$DIR/clippy.toml`: unknown field `foobar`, expected one of `avoid-breaking-exported-api`, `msrv`, `blacklisted-names`, `cognitive-complexity-threshold`, `cyclomatic-complexity-threshold`, `doc-valid-idents`, `too-many-arguments-threshold`, `type-complexity-threshold`, `single-char-binding-names-threshold`, `too-large-for-stack`, `enum-variant-name-threshold`, `enum-variant-size-threshold`, `verbose-bit-mask-threshold`, `literal-representation-threshold`, `trivial-copy-size-limit`, `pass-by-value-size-limit`, `too-many-lines-threshold`, `array-size-threshold`, `vec-box-size-threshold`, `max-trait-bounds`, `max-struct-bools`, `max-fn-params-bools`, `warn-on-all-wildcard-imports`, `disallowed-methods`, `disallowed-types`, `unreadable-literal-lint-fractions`, `upper-case-acronyms-aggressive`, `cargo-ignore-publish`, `standard-macro-braces`, `third-party` at line 5 column 1
+error: error reading Clippy's configuration file `$DIR/clippy.toml`: unknown field `foobar`, expected one of `avoid-breaking-exported-api`, `msrv`, `blacklisted-names`, `cognitive-complexity-threshold`, `cyclomatic-complexity-threshold`, `doc-valid-idents`, `too-many-arguments-threshold`, `type-complexity-threshold`, `single-char-binding-names-threshold`, `too-large-for-stack`, `enum-variant-name-threshold`, `enum-variant-size-threshold`, `verbose-bit-mask-threshold`, `literal-representation-threshold`, `trivial-copy-size-limit`, `pass-by-value-size-limit`, `too-many-lines-threshold`, `array-size-threshold`, `vec-box-size-threshold`, `max-trait-bounds`, `max-struct-bools`, `max-fn-params-bools`, `warn-on-all-wildcard-imports`, `disallowed-methods`, `disallowed-types`, `unreadable-literal-lint-fractions`, `upper-case-acronyms-aggressive`, `cargo-ignore-publish`, `standard-macro-braces`, `enforced-import-renames`, `third-party` at line 5 column 1
 
 error: aborting due to previous error