1 files changed, 77 insertions, 0 deletions
diff --git a/lib/erb/util.rb b/lib/erb/util.rb
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+# frozen_string_literal: true
+
+# Load CGI.escapeHTML and CGI.escapeURIComponent.
+# CRuby:
+#   cgi.gem v0.1.0+ (Ruby 2.7-3.4) and Ruby 4.0+ stdlib have 'cgi/escape' and CGI.escapeHTML.
+#   cgi.gem v0.3.3+ (Ruby 3.2-3.4) and Ruby 4.0+ stdlib have CGI.escapeURIComponent.
+# JRuby: cgi.gem has a Java extension 'cgi/escape'.
+# TruffleRuby: lib/truffle/cgi/escape.rb requires 'cgi/util'.
+require 'cgi/escape'
+
+# Load or define ERB::Escape#html_escape.
+# We don't build the C extension 'cgi/escape' for JRuby, TruffleRuby, and WASM.
+# miniruby (used by CRuby build scripts) also fails to load erb/escape.so.
+begin
+  require 'erb/escape'
+rescue LoadError
+  # ERB::Escape
+  #
+  # A subset of ERB::Util. Unlike ERB::Util#html_escape, we expect/hope
+  # Rails will not monkey-patch ERB::Escape#html_escape.
+  module ERB::Escape
+    # :stopdoc:
+    def html_escape(s)
+      CGI.escapeHTML(s.to_s)
+    end
+    module_function :html_escape
+  end
+end
+
+# ERB::Util
+#
+# A utility module for conversion routines, often handy in HTML generation.
+module ERB::Util
+  #
+  # A utility method for escaping HTML tag characters in _s_.
+  #
+  #   require "erb"
+  #   include ERB::Util
+  #
+  #   puts html_escape("is a > 0 & a < 10?")
+  #
+  # _Generates_
+  #
+  #   is a &gt; 0 &amp; a &lt; 10?
+  #
+  include ERB::Escape # html_escape
+  module_function :html_escape
+  alias h html_escape
+  module_function :h
+
+  if CGI.respond_to?(:escapeURIComponent)
+    #
+    # A utility method for encoding the String _s_ as a URL.
+    #
+    #   require "erb"
+    #   include ERB::Util
+    #
+    #   puts url_encode("Programming Ruby:  The Pragmatic Programmer's Guide")
+    #
+    # _Generates_
+    #
+    #   Programming%20Ruby%3A%20%20The%20Pragmatic%20Programmer%27s%20Guide
+    #
+    def url_encode(s)
+      CGI.escapeURIComponent(s.to_s)
+    end
+  else # cgi.gem <= v0.3.2
+    def url_encode(s)
+      s.to_s.b.gsub(/[^a-zA-Z0-9_\-.~]/n) do |m|
+        sprintf("%%%02X", m.unpack1("C"))
+      end
+    end
+  end
+  alias u url_encode
+  module_function :u
+  module_function :url_encode
+end