diff --git a/Gemfile.lock b/Gemfile.lock
index 5ff9311..fddb8ca 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -2,76 +2,78 @@ PATH
   remote: .
   specs:
     rubytree (2.1.0)
-      json (~> 2.0, > 2.3.1)
+      json (~> 2.0, > 2.9)
 
 GEM
   remote: https://rubygems.org/
   specs:
     ast (2.4.2)
+    date (3.4.1)
     diff-lcs (1.5.1)
     docile (1.4.1)
-    json (2.7.2)
+    json (2.9.1)
     language_server-protocol (3.17.0.3)
-    parallel (1.26.2)
-    parser (3.3.4.2)
+    parallel (1.26.3)
+    parser (3.3.6.0)
       ast (~> 2.4.1)
       racc
-    power_assert (2.0.3)
-    psych (5.1.2)
+    power_assert (2.0.4)
+    psych (5.2.2)
+      date
       stringio
     racc (1.8.1)
     rainbow (3.1.1)
     rake (13.2.1)
-    rdoc (6.7.0)
+    rdoc (6.10.0)
       psych (>= 4.0.0)
-    regexp_parser (2.9.2)
-    rexml (3.3.9)
+    regexp_parser (2.9.3)
     rspec (3.13.0)
       rspec-core (~> 3.13.0)
       rspec-expectations (~> 3.13.0)
       rspec-mocks (~> 3.13.0)
-    rspec-core (3.13.0)
+    rspec-core (3.13.2)
       rspec-support (~> 3.13.0)
-    rspec-expectations (3.13.1)
+    rspec-expectations (3.13.3)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-mocks (3.13.1)
+    rspec-mocks (3.13.2)
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.13.0)
-    rspec-support (3.13.1)
+    rspec-support (3.13.2)
     rtags (0.97)
     rtagstask (0.0.4)
       rtags (> 0.0.0)
-    rubocop (1.65.1)
+    rubocop (1.69.2)
       json (~> 2.3)
       language_server-protocol (>= 3.17.0)
       parallel (~> 1.10)
       parser (>= 3.3.0.2)
       rainbow (>= 2.2.2, < 4.0)
-      regexp_parser (>= 2.4, < 3.0)
-      rexml (>= 3.2.5, < 4.0)
-      rubocop-ast (>= 1.31.1, < 2.0)
+      regexp_parser (>= 2.9.3, < 3.0)
+      rubocop-ast (>= 1.36.2, < 2.0)
       ruby-progressbar (~> 1.7)
-      unicode-display_width (>= 2.4.0, < 3.0)
-    rubocop-ast (1.32.0)
+      unicode-display_width (>= 2.4.0, < 4.0)
+    rubocop-ast (1.37.0)
       parser (>= 3.3.1.0)
     rubocop-rake (0.6.0)
       rubocop (~> 1.0)
-    rubocop-rspec (3.0.4)
+    rubocop-rspec (3.3.0)
       rubocop (~> 1.61)
     ruby-progressbar (1.13.0)
     simplecov (0.22.0)
       docile (~> 1.1)
       simplecov-html (~> 0.11)
       simplecov_json_formatter (~> 0.1)
-    simplecov-html (0.12.3)
+    simplecov-html (0.13.1)
     simplecov-lcov (0.8.0)
     simplecov_json_formatter (0.1.4)
-    stringio (3.1.1)
-    test-unit (3.6.2)
+    stringio (3.1.2)
+    test-unit (3.6.7)
       power_assert
-    unicode-display_width (2.5.0)
-    yard (0.9.36)
+    unicode-display_width (3.1.2)
+      unicode-emoji (~> 4.0, >= 4.0.4)
+    unicode-emoji (4.0.4)
+    yard (0.9.37)
 
 PLATFORMS
   ruby
@@ -79,17 +81,17 @@ PLATFORMS
 DEPENDENCIES
   bundler (~> 2.3)
   rake (~> 13.2)
-  rdoc (~> 6.7)
-  rspec (~> 3.0, > 3.10)
+  rdoc (~> 6.10)
+  rspec (~> 3.0, >= 3.13)
   rtagstask (~> 0.0.4)
-  rubocop (~> 1.65)
+  rubocop (~> 1.69)
   rubocop-rake (~> 0.6)
-  rubocop-rspec (~> 3.0)
+  rubocop-rspec (~> 3.3)
   rubytree!
   simplecov (~> 0.22)
   simplecov-lcov (~> 0.8)
   test-unit (~> 3.6)
-  yard (~> 0.0, >= 0.9.36)
+  yard (~> 0.0, >= 0.9.37)
 
 BUNDLED WITH
    2.3.4
diff --git a/rubytree.gemspec b/rubytree.gemspec
index 50022cb..8f970aa 100644
--- a/rubytree.gemspec
+++ b/rubytree.gemspec
@@ -63,21 +63,21 @@ Gem::Specification.new do |s|
                             '--main', 'README.md',
                             '--quiet']
 
-  s.add_runtime_dependency 'json', '~> 2.0', '> 2.3.1'
+  s.add_runtime_dependency 'json', '~> 2.0', '> 2.9'
 
   # NOTE: Rake is added as a development and test dependency in the Gemfile.
   s.add_development_dependency 'bundler', '~> 2.3'
   s.add_development_dependency 'rake', '~> 13.2'
-  s.add_development_dependency 'rdoc', '~> 6.7'
-  s.add_development_dependency 'rspec', '~> 3.0', '> 3.10'
+  s.add_development_dependency 'rdoc', '~> 6.10'
+  s.add_development_dependency 'rspec', '~> 3.0', '>= 3.13'
   s.add_development_dependency 'rtagstask', '~> 0.0.4'
-  s.add_development_dependency 'rubocop', '~> 1.65'
+  s.add_development_dependency 'rubocop', '~> 1.69'
   s.add_development_dependency 'rubocop-rake', '~> 0.6'
-  s.add_development_dependency 'rubocop-rspec', '~> 3.0'
+  s.add_development_dependency 'rubocop-rspec', '~> 3.3'
   s.add_development_dependency 'simplecov', '~> 0.22'
   s.add_development_dependency 'simplecov-lcov', '~> 0.8'
   s.add_development_dependency 'test-unit', '~> 3.6'
-  s.add_development_dependency 'yard', '~> 0.0', '>= 0.9.36'
+  s.add_development_dependency 'yard', '~> 0.0', '>= 0.9.37'
 
   s.post_install_message = <<-END_MESSAGE
     ========================================================================