From 762249868136febf62bc118571bd5abf5748d213 Mon Sep 17 00:00:00 2001
From: Tejas Bubane <tejasbubane@gmail.com>
Date: Thu, 10 Sep 2020 10:19:24 +0530
Subject: [PATCH] [Fix #8684] Fix an error for `Lint/InterpolationCheck` cop

Closes https://github.com/rubocop-hq/rubocop/issues/8684
---
 changelog/fix_fix_an_error_for_lintinterpolationcheck.md | 1 +
 lib/rubocop/cop/lint/interpolation_check.rb              | 9 +++++++--
 spec/rubocop/cop/lint/interpolation_check_spec.rb        | 6 ++++++
 3 files changed, 14 insertions(+), 2 deletions(-)
 create mode 100644 changelog/fix_fix_an_error_for_lintinterpolationcheck.md

diff --git a/changelog/fix_fix_an_error_for_lintinterpolationcheck.md b/changelog/fix_fix_an_error_for_lintinterpolationcheck.md
new file mode 100644
index 00000000000..59819ab1a64
--- /dev/null
+++ b/changelog/fix_fix_an_error_for_lintinterpolationcheck.md
@@ -0,0 +1 @@
+* [#8684](https://github.com/rubocop-hq/rubocop/issues/8684): Fix an error for `Lint/InterpolationCheck` cop. ([@tejasbubane][])
diff --git a/lib/rubocop/cop/lint/interpolation_check.rb b/lib/rubocop/cop/lint/interpolation_check.rb
index 70d3fa9e02a..b6edc43e490 100644
--- a/lib/rubocop/cop/lint/interpolation_check.rb
+++ b/lib/rubocop/cop/lint/interpolation_check.rb
@@ -23,10 +23,11 @@ class InterpolationCheck < Base
               'Use double quoted strings if you need interpolation.'
 
         def on_str(node)
-          parent = node.parent
-          return if parent && (parent.dstr_type? || parent.regexp_type?)
+          return unless node
+          return if string_or_regex?(node.parent)
           return unless /(?<!\\)#\{.*\}/.match?(node.source)
           return if heredoc?(node)
+          return unless node.loc.begin && node.loc.end
 
           add_offense(node) do |corrector|
             autocorrect(corrector, node)
@@ -35,6 +36,10 @@ def on_str(node)
 
         private
 
+        def string_or_regex?(node)
+          node&.dstr_type? || node&.regexp_type?
+        end
+
         def autocorrect(corrector, node)
           starting_token, ending_token = if node.source.include?('"')
                                            ['%{', '}']
diff --git a/spec/rubocop/cop/lint/interpolation_check_spec.rb b/spec/rubocop/cop/lint/interpolation_check_spec.rb
index ee7b109db15..3c0877de09b 100644
--- a/spec/rubocop/cop/lint/interpolation_check_spec.rb
+++ b/spec/rubocop/cop/lint/interpolation_check_spec.rb
@@ -60,4 +60,10 @@
       foo = "alpha #{variable} beta \#{gamma}\" delta"
     RUBY
   end
+
+  it 'does not register offense for strings in %w()' do
+    expect_no_offenses(<<~'RUBY')
+      %w("#{a}-foo")
+    RUBY
+  end
 end