Auto merge of #9366 - Alexendoo:manual_string_new, r=xFrednet

Rename `manual_empty_string_creation` and move to pedantic

Renames it to `manual_string_new` and moves it to the pedantic category

Pedantic because it's a fairly minor style change but could be very noisy

changelog: *doesn't need its own entry, but remember to s/manual_empty_string_creation/manual_string_new/ the changelog entry for #9295*

r? `@xFrednet` to get it in before the upcoming sync as this isn't a `cargo dev rename_lint` style rename

CHANGELOG.md

@@ -3831,7 +3831,6 @@ Released 2018-09-13
 [`manual_assert`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_assert
 [`manual_async_fn`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_async_fn
 [`manual_bits`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_bits
-[`manual_empty_string_creations`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_empty_string_creations
 [`manual_filter_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_filter_map
 [`manual_find`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_find
 [`manual_find_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_find_map
@@ -3847,6 +3846,7 @@ Released 2018-09-13
 [`manual_saturating_arithmetic`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_saturating_arithmetic
 [`manual_split_once`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_split_once
 [`manual_str_repeat`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_str_repeat
+[`manual_string_new`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_string_new
 [`manual_strip`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_strip
 [`manual_swap`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_swap
 [`manual_unwrap_or`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_unwrap_or

clippy_lints/src/lib.register_all.rs

@@ -122,7 +122,6 @@ store.register_group(true, "clippy::all", Some("clippy_all"), vec![
     LintId::of(main_recursion::MAIN_RECURSION),
     LintId::of(manual_async_fn::MANUAL_ASYNC_FN),
     LintId::of(manual_bits::MANUAL_BITS),
-    LintId::of(manual_empty_string_creations::MANUAL_EMPTY_STRING_CREATIONS),
     LintId::of(manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE),
     LintId::of(manual_rem_euclid::MANUAL_REM_EUCLID),
     LintId::of(manual_retain::MANUAL_RETAIN),

clippy_lints/src/lib.register_lints.rs

@@ -240,11 +240,11 @@ store.register_lints(&[
     manual_assert::MANUAL_ASSERT,
     manual_async_fn::MANUAL_ASYNC_FN,
     manual_bits::MANUAL_BITS,
-    manual_empty_string_creations::MANUAL_EMPTY_STRING_CREATIONS,
     manual_instant_elapsed::MANUAL_INSTANT_ELAPSED,
     manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE,
     manual_rem_euclid::MANUAL_REM_EUCLID,
     manual_retain::MANUAL_RETAIN,
+    manual_string_new::MANUAL_STRING_NEW,
     manual_strip::MANUAL_STRIP,
     map_unit_fn::OPTION_MAP_UNIT_FN,
     map_unit_fn::RESULT_MAP_UNIT_FN,

clippy_lints/src/lib.register_pedantic.rs

@@ -48,6 +48,7 @@ store.register_group(true, "clippy::pedantic", Some("clippy_pedantic"), vec![
     LintId::of(macro_use::MACRO_USE_IMPORTS),
     LintId::of(manual_assert::MANUAL_ASSERT),
     LintId::of(manual_instant_elapsed::MANUAL_INSTANT_ELAPSED),
+    LintId::of(manual_string_new::MANUAL_STRING_NEW),
     LintId::of(matches::MATCH_BOOL),
     LintId::of(matches::MATCH_ON_VEC_ITEMS),
     LintId::of(matches::MATCH_SAME_ARMS),

clippy_lints/src/lib.register_style.rs

@@ -43,7 +43,6 @@ store.register_group(true, "clippy::style", Some("clippy_style"), vec![
     LintId::of(main_recursion::MAIN_RECURSION),
     LintId::of(manual_async_fn::MANUAL_ASYNC_FN),
     LintId::of(manual_bits::MANUAL_BITS),
-    LintId::of(manual_empty_string_creations::MANUAL_EMPTY_STRING_CREATIONS),
     LintId::of(manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE),
     LintId::of(match_result_ok::MATCH_RESULT_OK),
     LintId::of(matches::COLLAPSIBLE_MATCH),

clippy_lints/src/lib.rs

@@ -267,11 +267,11 @@ mod main_recursion;
 mod manual_assert;
 mod manual_async_fn;
 mod manual_bits;
-mod manual_empty_string_creations;
 mod manual_instant_elapsed;
 mod manual_non_exhaustive;
 mod manual_rem_euclid;
 mod manual_retain;
+mod manual_string_new;
 mod manual_strip;
 mod map_unit_fn;
 mod match_result_ok;
@@ -894,7 +894,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| Box::new(std_instead_of_core::StdReexports::default()));
     store.register_late_pass(|| Box::new(manual_instant_elapsed::ManualInstantElapsed));
     store.register_late_pass(|| Box::new(partialeq_to_none::PartialeqToNone));
-    store.register_late_pass(|| Box::new(manual_empty_string_creations::ManualEmptyStringCreations));
+    store.register_late_pass(|| Box::new(manual_string_new::ManualStringNew));
     store.register_late_pass(|| Box::new(unused_peekable::UnusedPeekable));
     // add lints here, do not remove this comment, it's used in `new_lint`
 }

clippy_lints/src/manual_string_new.rs

@@ -29,13 +29,13 @@ declare_clippy_lint! {
     /// let b = String::new();
     /// ```
     #[clippy::version = "1.65.0"]
-    pub MANUAL_EMPTY_STRING_CREATIONS,
-    style,
+    pub MANUAL_STRING_NEW,
+    pedantic,
     "empty String is being created manually"
 }
-declare_lint_pass!(ManualEmptyStringCreations => [MANUAL_EMPTY_STRING_CREATIONS]);
+declare_lint_pass!(ManualStringNew => [MANUAL_STRING_NEW]);
 
-impl LateLintPass<'_> for ManualEmptyStringCreations {
+impl LateLintPass<'_> for ManualStringNew {
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
         if expr.span.from_expansion() {
             return;
@@ -75,11 +75,10 @@ fn is_expr_kind_empty_str(expr_kind: &ExprKind<'_>) -> bool {
     false
 }
 
-/// Emits the `MANUAL_EMPTY_STRING_CREATION` warning and suggests the appropriate fix.
 fn warn_then_suggest(cx: &LateContext<'_>, span: Span) {
     span_lint_and_sugg(
         cx,
-        MANUAL_EMPTY_STRING_CREATIONS,
+        MANUAL_STRING_NEW,
         span,
         "empty String is being created manually",
         "consider using",

tests/ui/manual_string_new.fixed

@@ -1,6 +1,6 @@
 // run-rustfix
 
-#![warn(clippy::manual_empty_string_creations)]
+#![warn(clippy::manual_string_new)]
 
 macro_rules! create_strings_from_macro {
     // When inside a macro, nothing should warn to prevent false positives.

tests/ui/manual_string_new.rs

@@ -1,6 +1,6 @@
 // run-rustfix
 
-#![warn(clippy::manual_empty_string_creations)]
+#![warn(clippy::manual_string_new)]
 
 macro_rules! create_strings_from_macro {
     // When inside a macro, nothing should warn to prevent false positives.

tests/ui/manual_string_new.stderr

@@ -1,55 +1,55 @@
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:15:13
+  --> $DIR/manual_string_new.rs:15:13
    |
 LL |     let _ = "".to_string();
    |             ^^^^^^^^^^^^^^ help: consider using: `String::new()`
    |
-   = note: `-D clippy::manual-empty-string-creations` implied by `-D warnings`
+   = note: `-D clippy::manual-string-new` implied by `-D warnings`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:18:13
+  --> $DIR/manual_string_new.rs:18:13
    |
 LL |     let _ = "".to_owned();
    |             ^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:21:21
+  --> $DIR/manual_string_new.rs:21:21
    |
 LL |     let _: String = "".into();
    |                     ^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:28:13
+  --> $DIR/manual_string_new.rs:28:13
    |
 LL |     let _ = String::from("");
    |             ^^^^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:29:13
+  --> $DIR/manual_string_new.rs:29:13
    |
 LL |     let _ = <String>::from("");
    |             ^^^^^^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:34:13
+  --> $DIR/manual_string_new.rs:34:13
    |
 LL |     let _ = String::try_from("").unwrap();
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:40:21
+  --> $DIR/manual_string_new.rs:40:21
    |
 LL |     let _: String = From::from("");
    |                     ^^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:45:21
+  --> $DIR/manual_string_new.rs:45:21
    |
 LL |     let _: String = TryFrom::try_from("").unwrap();
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `String::new()`
 
 error: empty String is being created manually
-  --> $DIR/manual_empty_string_creations.rs:48:21
+  --> $DIR/manual_string_new.rs:48:21
    |
 LL |     let _: String = TryFrom::try_from("").expect("this should warn");
    |                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using: `String::new()`

tests/ui/unnecessary_owned_empty_strings.fixed

@@ -12,7 +12,7 @@ fn main() {
     ref_str_argument("");
 
     // should be linted
-    #[allow(clippy::manual_empty_string_creations)]
+    #[allow(clippy::manual_string_new)]
     ref_str_argument("");
 
     // should not be linted

tests/ui/unnecessary_owned_empty_strings.rs

@@ -12,7 +12,7 @@ fn main() {
     ref_str_argument(&String::new());
 
     // should be linted
-    #[allow(clippy::manual_empty_string_creations)]
+    #[allow(clippy::manual_string_new)]
     ref_str_argument(&String::from(""));
 
     // should not be linted