bumping ruby version and rubocop fixes (#39)

.rubocop.yml

@@ -3,7 +3,7 @@ require:
   - rubocop-rake
 
 AllCops:
-  TargetRubyVersion: 2.7
+  TargetRubyVersion: 3.0
   NewCops: enable
 
 Style/SpecialGlobalVars:

Gemfile

@@ -4,3 +4,18 @@ source 'https://rubygems.org'
 
 # Specify your gem's dependencies in exiftoolr.gemspec
 gemspec
+
+group :development do
+  gem 'bundler'
+  gem 'minitest'
+  gem 'minitest-great_expectations'
+  gem 'minitest-reporters' unless ENV['CI']
+  gem 'rake'
+  gem 'rubocop'
+  gem 'rubocop-minitest'
+  gem 'rubocop-rake'
+  gem 'simplecov'
+  gem 'simplecov-console'
+  gem 'simplecov_json_formatter'
+  gem 'yard'
+end

exiftool.gemspec

@@ -16,24 +16,12 @@ Gem::Specification.new do |spec|
 
   spec.metadata['rubygems_mfa_required'] = 'true'
 
-  spec.required_ruby_version = '>= 2.7'
+  spec.required_ruby_version = '>= 3.0'
 
   spec.files         = `git ls-files -- lib`.split($/)
   spec.require_paths = %w[lib]
 
   spec.requirements << 'ExifTool (see http://exiftool.org)'
 
   spec.add_dependency 'json'
-  spec.add_development_dependency 'bundler'
-  spec.add_development_dependency 'minitest'
-  spec.add_development_dependency 'minitest-great_expectations'
-  spec.add_development_dependency 'minitest-reporters' unless ENV['CI']
-  spec.add_development_dependency 'rake'
-  spec.add_development_dependency 'rubocop'
-  spec.add_development_dependency 'rubocop-minitest'
-  spec.add_development_dependency 'rubocop-rake'
-  spec.add_development_dependency 'simplecov'
-  spec.add_development_dependency 'simplecov-console'
-  spec.add_development_dependency 'simplecov_json_formatter'
-  spec.add_development_dependency 'yard'
 end

lib/exiftool/field_parser.rb

@@ -6,9 +6,9 @@ class Exiftool
   # Exiftool FiledParser Class
   class FieldParser
     WORD_BOUNDARY_RES = [/([A-Z\d]+)([A-Z][a-z])/, /([a-z\d])([A-Z])/].freeze
-    FRACTION_RE = %r{^(\d+)/(\d+)$}.freeze
-    YMD_RE = /\A(\d{4}):(\d{2}):(\d{2})\b/.freeze
-    ZERO_DATE_RE = /\A[+:0 ]+\z/.freeze
+    FRACTION_RE = %r{^(\d+)/(\d+)$}
+    YMD_RE = /\A(\d{4}):(\d{2}):(\d{2})\b/
+    ZERO_DATE_RE = /\A[+:0 ]+\z/
 
     attr_reader :key, :display_key, :sym_key, :raw_value