Rollup merge of #5419 - dtolnay:unreadable, r=flip1995

Downgrade unreadable_literal to pedantic

As motivated by #5418. This is the top most commonly suppressed Clippy style lint, which indicates that the community has decided they don't share Clippy's opinion on the best style of this.

I've left the lint in as pedantic, though it could be that "restriction" would be better -- I can see this lint being useful as an opt-in restriction in some codebases.

changelog: Remove unreadable_literal from default set of enabled lints

clippy_lints/src/lib.rs

@@ -1105,6 +1105,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(&items_after_statements::ITEMS_AFTER_STATEMENTS),
         LintId::of(&large_stack_arrays::LARGE_STACK_ARRAYS),
         LintId::of(&literal_representation::LARGE_DIGIT_GROUPS),
+        LintId::of(&literal_representation::UNREADABLE_LITERAL),
         LintId::of(&loops::EXPLICIT_INTO_ITER_LOOP),
         LintId::of(&loops::EXPLICIT_ITER_LOOP),
         LintId::of(&macro_use::MACRO_USE_IMPORTS),
@@ -1229,7 +1230,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(&lifetimes::NEEDLESS_LIFETIMES),
         LintId::of(&literal_representation::INCONSISTENT_DIGIT_GROUPING),
         LintId::of(&literal_representation::MISTYPED_LITERAL_SUFFIXES),
-        LintId::of(&literal_representation::UNREADABLE_LITERAL),
         LintId::of(&loops::EMPTY_LOOP),
         LintId::of(&loops::EXPLICIT_COUNTER_LOOP),
         LintId::of(&loops::FOR_KV_MAP),
@@ -1436,7 +1436,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
         LintId::of(&len_zero::LEN_ZERO),
         LintId::of(&let_if_seq::USELESS_LET_IF_SEQ),
         LintId::of(&literal_representation::INCONSISTENT_DIGIT_GROUPING),
-        LintId::of(&literal_representation::UNREADABLE_LITERAL),
         LintId::of(&loops::EMPTY_LOOP),
         LintId::of(&loops::FOR_KV_MAP),
         LintId::of(&loops::NEEDLESS_RANGE_LOOP),

clippy_lints/src/literal_representation.rs

@@ -27,7 +27,7 @@ declare_clippy_lint! {
     /// let x: u64 = 61864918973511;
     /// ```
     pub UNREADABLE_LITERAL,
-    style,
+    pedantic,
     "long integer literal without underscores"
 }
 

src/lintlist/mod.rs

@@ -2301,7 +2301,7 @@ pub static ref ALL_LINTS: Vec<Lint> = vec![
     },
     Lint {
         name: "unreadable_literal",
-        group: "style",
+        group: "pedantic",
         desc: "long integer literal without underscores",
         deprecation: None,
         module: "literal_representation",

tests/ui/approx_const.rs

@@ -1,5 +1,5 @@
 #[warn(clippy::approx_constant)]
-#[allow(unused, clippy::shadow_unrelated, clippy::similar_names, clippy::unreadable_literal)]
+#[allow(unused, clippy::shadow_unrelated, clippy::similar_names)]
 fn main() {
     let my_e = 2.7182;
     let almost_e = 2.718;

tests/ui/inconsistent_digit_grouping.fixed

@@ -1,5 +1,6 @@
 // run-rustfix
 #[warn(clippy::inconsistent_digit_grouping)]
+#[deny(clippy::unreadable_literal)]
 #[allow(unused_variables, clippy::excessive_precision)]
 fn main() {
     macro_rules! mac1 {

tests/ui/inconsistent_digit_grouping.rs

@@ -1,5 +1,6 @@
 // run-rustfix
 #[warn(clippy::inconsistent_digit_grouping)]
+#[deny(clippy::unreadable_literal)]
 #[allow(unused_variables, clippy::excessive_precision)]
 fn main() {
     macro_rules! mac1 {

tests/ui/inconsistent_digit_grouping.stderr

@@ -1,5 +1,5 @@
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:25:16
+  --> $DIR/inconsistent_digit_grouping.rs:26:16
    |
 LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f32);
    |                ^^^^^^^^ help: consider: `123_456`
@@ -7,57 +7,61 @@ LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f
    = note: `-D clippy::inconsistent-digit-grouping` implied by `-D warnings`
 
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:25:26
+  --> $DIR/inconsistent_digit_grouping.rs:26:26
    |
 LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f32);
    |                          ^^^^^^^^^^ help: consider: `12_345_678`
 
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:25:38
+  --> $DIR/inconsistent_digit_grouping.rs:26:38
    |
 LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f32);
    |                                      ^^^^^^^^ help: consider: `1_234_567`
 
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:25:48
+  --> $DIR/inconsistent_digit_grouping.rs:26:48
    |
 LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f32);
    |                                                ^^^^^^^^^^^^^^ help: consider: `1_234.567_8_f32`
 
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:25:64
+  --> $DIR/inconsistent_digit_grouping.rs:26:64
    |
 LL |     let bad = (1_23_456, 1_234_5678, 1234_567, 1_234.5678_f32, 1.234_5678_f32);
    |                                                                ^^^^^^^^^^^^^^ help: consider: `1.234_567_8_f32`
 
 error: long literal lacking separators
-  --> $DIR/inconsistent_digit_grouping.rs:28:13
+  --> $DIR/inconsistent_digit_grouping.rs:29:13
    |
 LL |     let _ = 0x100000;
    |             ^^^^^^^^ help: consider: `0x0010_0000`
    |
-   = note: `-D clippy::unreadable-literal` implied by `-D warnings`
+note: the lint level is defined here
+  --> $DIR/inconsistent_digit_grouping.rs:3:8
+   |
+LL | #[deny(clippy::unreadable_literal)]
+   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: long literal lacking separators
-  --> $DIR/inconsistent_digit_grouping.rs:29:13
+  --> $DIR/inconsistent_digit_grouping.rs:30:13
    |
 LL |     let _ = 0x1000000;
    |             ^^^^^^^^^ help: consider: `0x0100_0000`
 
 error: long literal lacking separators
-  --> $DIR/inconsistent_digit_grouping.rs:30:13
+  --> $DIR/inconsistent_digit_grouping.rs:31:13
    |
 LL |     let _ = 0x10000000;
    |             ^^^^^^^^^^ help: consider: `0x1000_0000`
 
 error: long literal lacking separators
-  --> $DIR/inconsistent_digit_grouping.rs:31:13
+  --> $DIR/inconsistent_digit_grouping.rs:32:13
    |
 LL |     let _ = 0x100000000_u64;
    |             ^^^^^^^^^^^^^^^ help: consider: `0x0001_0000_0000_u64`
 
 error: digits grouped inconsistently by underscores
-  --> $DIR/inconsistent_digit_grouping.rs:34:18
+  --> $DIR/inconsistent_digit_grouping.rs:35:18
    |
 LL |     let _: f32 = 1_23_456.;
    |                  ^^^^^^^^^ help: consider: `123_456.`