Fix an incorrect autocorrect for Rails/SelectMap when select has …

…no receiver and method chains are used

This commit fixes an incorrect autocorrect for `Rails/SelectMap` when `select` has no receiver and method chains are used between `select` and `map`, as follows:

Before autocorrect
```ruby
select(:column_name).where(conditions).map(&:column_name)
```

After autocorrect (syntax error)
```ruby
.where(conditions)pluck(:column_name)
```

changelog/fix_fix_an_incorrect_autocorrect_for.md

@@ -0,0 +1 @@
+* [#1390](https://github.com/rubocop/rubocop-rails/pull/1390): Fix an incorrect autocorrect for `Rails/SelectMap` when `select` has no receiver and method chains are used. ([@masato-bkn][])

lib/rubocop/cop/rails/select_map.rb

@@ -54,7 +54,7 @@ def find_select_node(node, column_name)
 
         # rubocop:disable Metrics/AbcSize
         def autocorrect(corrector, select_node, node, preferred_method)
-          corrector.remove(select_node.loc.dot || node.loc.dot)
+          corrector.remove(select_node.parent.loc.dot)
           corrector.remove(select_node.loc.selector.begin.join(select_node.source_range.end))
           corrector.replace(node.loc.selector.begin.join(node.source_range.end), preferred_method)
         end

spec/rubocop/cop/rails/select_map_spec.rb

@@ -45,7 +45,7 @@
     RUBY
   end
 
-  it 'registers an offense when using `select(:column_name).map(&:column_name)` without receiver model' do
+  it 'registers an offense when using `select(:column_name).map(&:column_name)` without receiver' do
     expect_offense(<<~RUBY)
       select(:column_name).map(&:column_name)
       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Use `pluck(:column_name)` instead of `select` with `map`.
@@ -56,6 +56,17 @@
     RUBY
   end
 
+  it 'registers an offense when using `select(:column_name).where(conditions).map(&:column_name)` without receiver' do
+    expect_offense(<<~RUBY)
+      select(:column_name).where(conditions).map(&:column_name)
+      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Use `pluck(:column_name)` instead of `select` with `map`.
+    RUBY
+
+    expect_correction(<<~RUBY)
+      where(conditions).pluck(:column_name)
+    RUBY
+  end
+
   it 'handles safe navigation chain' do
     expect_offense(<<~RUBY)
       relation&.select(:column_name)&.map(&:column_name)