From 018a04280a60660be2e09b91a4e2284f45a2f802 Mon Sep 17 00:00:00 2001
From: avrusanov <49242440+avrusanov@users.noreply.github.com>
Date: Fri, 12 Jun 2020 13:03:39 +0500
Subject: [PATCH] [Fix #8132] Fix handling of names like _ and i with
 Naming/MethodName and EnforcedStyle: camelCase (#8140)

---
 CHANGELOG.md                                  | 2 ++
 lib/rubocop/cop/mixin/configurable_naming.rb  | 2 +-
 spec/rubocop/cop/naming/variable_name_spec.rb | 8 ++++++++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9bc193cac1b..166f0e55c92 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 
 ### Bug fixes
 
+* [#8132](https://github.com/rubocop-hq/rubocop/issues/8132): Fix the problem with `Naming/MethodName: EnforcedStyle: camelCase` and `_` or `i` variables. ([@avrusanov][])
 * [#8115](https://github.com/rubocop-hq/rubocop/issues/8115): Fix false negative for `Lint::FormatParameterMismatch` when argument contains formatting. ([@andrykonchin][])
 * [#8131](https://github.com/rubocop-hq/rubocop/pull/8131): Fix false positive for `Style/RedundantRegexpEscape` with escaped delimiters. ([@owst][])
 * [#8124](https://github.com/rubocop-hq/rubocop/issues/8124): Fix a false positive for `Lint/FormatParameterMismatch` when using named parameters with escaped `%`. ([@koic][])
@@ -4586,3 +4587,4 @@
 [@ric2b]: https://github.com/ric2b
 [@burnettk]: https://github.com/burnettk
 [@andrykonchin]: https://github.com/andrykonchin
+[@avrusanov]: https://github.com/avrusanov
diff --git a/lib/rubocop/cop/mixin/configurable_naming.rb b/lib/rubocop/cop/mixin/configurable_naming.rb
index e9829a077a8..49734795aa8 100644
--- a/lib/rubocop/cop/mixin/configurable_naming.rb
+++ b/lib/rubocop/cop/mixin/configurable_naming.rb
@@ -9,7 +9,7 @@ module ConfigurableNaming
 
       FORMATS = {
         snake_case: /^@{0,2}[\da-z_]+[!?=]?$/,
-        camelCase:  /^@{0,2}_?[a-z][\da-zA-Z]+[!?=]?$/
+        camelCase:  /^@{0,2}(?:_|_?[a-z][\da-zA-Z]*)[!?=]?$/
       }.freeze
     end
   end
diff --git a/spec/rubocop/cop/naming/variable_name_spec.rb b/spec/rubocop/cop/naming/variable_name_spec.rb
index f7f4798fed8..5513771c36d 100644
--- a/spec/rubocop/cop/naming/variable_name_spec.rb
+++ b/spec/rubocop/cop/naming/variable_name_spec.rb
@@ -17,6 +17,14 @@
     it 'accepts assignment with indexing of self' do
       expect_no_offenses('self[:a] = b')
     end
+
+    it 'accepts local variables marked as unused' do
+      expect_no_offenses('_ = 1')
+    end
+
+    it 'accepts one symbol size local variables' do
+      expect_no_offenses('i = 1')
+    end
   end
 
   context 'when configured for snake_case' do