systematic revision of =~ usage in AV

Where appropriate, prefer the more concise Regexp#match?,
String#include?, String#start_with?, or String#end_with?

actionview/lib/action_view/helpers/asset_tag_helper.rb

 require 'active_support/core_ext/array/extract_options'
 require 'active_support/core_ext/hash/keys'
+require 'active_support/core_ext/regexp'
 require 'action_view/helpers/asset_url_helper'
 require 'action_view/helpers/tag_helper'
 
@@ -213,8 +214,8 @@ def image_tag(source, options={})
 
         src = options[:src] = path_to_image(source)
 
-        unless src =~ /^(?:cid|data):/ || src.blank?
-          options[:alt] = options.fetch(:alt){ image_alt(src) }
+        unless src.start_with?('cid:') || src.start_with?('data:') || src.blank?
+          options[:alt] = options.fetch(:alt) { image_alt(src) }
         end
 
         options[:width], options[:height] = extract_dimensions(options.delete(:size)) if options[:size]
@@ -322,9 +323,9 @@ def multiple_sources_tag(type, sources)
 
         def extract_dimensions(size)
           size = size.to_s
-          if size =~ %r{\A\d+x\d+\z}
+          if /\A\d+x\d+\z/.match?(size)
             size.split('x')
-          elsif size =~ %r{\A\d+\z}
+          elsif /\A\d+\z/.match?(size)
             [size, size]
           end
         end

actionview/lib/action_view/helpers/asset_url_helper.rb

 require 'zlib'
+require 'active_support/core_ext/regexp'
 
 module ActionView
   # = Action View Asset URL Helpers
@@ -131,8 +132,8 @@ def asset_path(source, options = {})
         raise ArgumentError, "nil is not a valid asset source" if source.nil?
 
         source = source.to_s
-        return "" unless source.present?
-        return source if source =~ URI_REGEXP
+        return '' if source.blank?
+        return source if URI_REGEXP.match?(source)
 
         tail, source = source[/([\?#].+)$/], source.sub(/([\?#].+)$/, ''.freeze)
 
@@ -213,19 +214,21 @@ def compute_asset_host(source = "", options = {})
         host = options[:host]
         host ||= config.asset_host if defined? config.asset_host
 
-        if host.respond_to?(:call)
-          arity = host.respond_to?(:arity) ? host.arity : host.method(:call).arity
-          args = [source]
-          args << request if request && (arity > 1 || arity < 0)
-          host = host.call(*args)
-        elsif host =~ /%d/
-          host = host % (Zlib.crc32(source) % 4)
+        if host
+          if host.respond_to?(:call)
+            arity = host.respond_to?(:arity) ? host.arity : host.method(:call).arity
+            args = [source]
+            args << request if request && (arity > 1 || arity < 0)
+            host = host.call(*args)
+          elsif host.include?('%d')
+            host = host % (Zlib.crc32(source) % 4)
+          end
         end
 
         host ||= request.base_url if request && options[:protocol] == :request
         return unless host
 
-        if host =~ URI_REGEXP
+        if URI_REGEXP.match?(host)
           host
         else
           protocol = options[:protocol] || config.default_asset_host_protocol || (request ? :request : :relative)

actionview/lib/action_view/helpers/translation_helper.rb

 require 'action_view/helpers/tag_helper'
 require 'active_support/core_ext/string/access'
+require 'active_support/core_ext/regexp'
 require 'i18n/exceptions'
 
 module ActionView
@@ -133,7 +134,7 @@ def scope_key_by_partial(key)
         end
 
         def html_safe_translation_key?(key)
-          key.to_s =~ /(\b|_|\.)html$/
+          /(\b|_|\.)html$/.match?(key.to_s)
         end
     end
   end

actionview/lib/action_view/helpers/url_helper.rb

@@ -2,6 +2,7 @@
 require 'active_support/core_ext/array/access'
 require 'active_support/core_ext/hash/keys'
 require 'active_support/core_ext/string/output_safety'
+require 'active_support/core_ext/regexp'
 
 module ActionView
   # = Action View URL Helpers
@@ -550,7 +551,7 @@ def current_page?(options)
 
         url_string.chomp!("/") if url_string.start_with?("/") && url_string != "/"
 
-        if url_string =~ /^\w+:\/\//
+        if %r{^\w+://}.match?(url_string)
           url_string == "#{request.protocol}#{request.host_with_port}#{request_uri}"
         else
           url_string == request_uri

actionview/lib/action_view/layouts.rb

-require "action_view/rendering"
-require "active_support/core_ext/module/remove_method"
+require 'action_view/rendering'
+require 'active_support/core_ext/module/remove_method'
+require 'active_support/core_ext/regexp'
 
 module ActionView
   # Layouts reverse the common pattern of including shared headers and footers in many templates to isolate changes in
@@ -279,7 +280,7 @@ def layout(layout, conditions = {})
       def _write_layout_method # :nodoc:
         remove_possible_method(:_layout)
 
-        prefixes    = _implied_layout_name =~ /\blayouts/ ? [] : ["layouts"]
+        prefixes = /\blayouts/.match?(_implied_layout_name) ? [] : ["layouts"]
         default_behavior = "lookup_context.find_all('#{_implied_layout_name}', #{prefixes.inspect}, false, [], { formats: formats }).first || super"
         name_clause = if name
           default_behavior

actionview/lib/action_view/renderer/partial_renderer.rb

-require 'action_view/renderer/partial_renderer/collection_caching'
 require 'concurrent/map'
+require 'active_support/core_ext/regexp'
+require 'action_view/renderer/partial_renderer/collection_caching'
 
 module ActionView
   class PartialIteration
@@ -386,7 +387,7 @@ def setup(context, options, block)
       end
 
       if as = options[:as]
-        raise_invalid_option_as(as) unless as.to_s =~ /\A[a-z_]\w*\z/
+        raise_invalid_option_as(as) unless /\A[a-z_]\w*\z/.match?(as.to_s)
         as = as.to_sym
       end
 

actionview/lib/action_view/renderer/template_renderer.rb

@@ -83,7 +83,7 @@ def resolve_layout(layout, keys, formats)
       case layout
       when String
         begin
-          if layout =~ /^\//
+          if layout.start_with?('/')
             with_fallbacks { find_template(layout, nil, false, [], details) }
           else
             find_template(layout, nil, false, [], details)

actionview/lib/action_view/template/error.rb

 require "active_support/core_ext/enumerable"
+require 'active_support/core_ext/regexp'
 
 module ActionView
   # = Action View Errors
@@ -35,7 +36,7 @@ def initialize(paths, path, prefixes, partial, details, *)
       prefixes = Array(prefixes)
       template_type = if partial
         "partial"
-      elsif path =~ /layouts/i
+      elsif /layouts/i.match?(path)
         'layout'
       else
         'template'

actionview/lib/action_view/template/handlers/erb.rb

 require 'erubis'
+require 'active_support/core_ext/regexp'
 
 module ActionView
   class Template
@@ -39,7 +40,7 @@ def add_expr(src, code, indicator)
 
         def add_expr_literal(src, code)
           flush_newline_if_pending(src)
-          if code =~ BLOCK_EXPR
+          if BLOCK_EXPR.match?(code)
             src << '@output_buffer.append= ' << code
           else
             src << '@output_buffer.append=(' << code << ');'
@@ -48,7 +49,7 @@ def add_expr_literal(src, code)
 
         def add_expr_escaped(src, code)
           flush_newline_if_pending(src)
-          if code =~ BLOCK_EXPR
+          if BLOCK_EXPR.match?(code)
             src << "@output_buffer.safe_expr_append= " << code
           else
             src << "@output_buffer.safe_expr_append=(" << code << ");"

actionview/lib/action_view/testing/resolvers.rb

+require 'active_support/core_ext/regexp'
 require 'action_view/template/resolver'
 
 module ActionView #:nodoc:
@@ -29,7 +30,7 @@ def query(path, exts, formats, _)
       templates = []
       @hash.each do |_path, array|
         source, updated_at = array
-        next unless _path =~ query
+        next unless query.match?(_path)
         handler, format, variant = extract_handler_and_format_and_variant(_path, formats)
         templates << Template.new(source, _path, handler,
           :virtual_path => path.virtual,
@@ -50,4 +51,3 @@ def query(path, exts, formats, _)
     end
   end
 end
-

actionview/test/actionpack/controller/layout_test.rb

 require 'abstract_unit'
 require 'active_support/core_ext/array/extract_options'
+require 'active_support/core_ext/regexp'
 
 # The view_paths array must be set on Base and not LayoutTest so that LayoutTest's inherited
 # method has access to the view_paths array when looking for a layout to automatically assign.
@@ -252,7 +253,7 @@ def test_layout_status_is_rendered
   end
 end
 
-unless RbConfig::CONFIG['host_os'] =~ /mswin|mingw/
+unless /mswin|mingw/.match?(RbConfig::CONFIG['host_os'])
   class LayoutSymlinkedTest < LayoutTest
     layout "symlinked/symlinked_layout"
   end