Fix Android Escaping of "'", "&" and "@".

Inspired by PR from Falko Richter:
netbe#133

lib/babelish/csv2android.rb

@@ -20,6 +20,8 @@ def language_filepaths(language)
 
     def process_value(row_value, default_value)
       value = super(row_value, default_value)
+      value = escape_android_characters(value)
+
       # if the value begins and ends with a quote we must leave them unescapted
       if value.size > 4 && value[0, 2] == "\\\"" && value[value.size - 2, value.size] == "\\\""
         value[0, 2] = "\""
@@ -28,6 +30,14 @@ def process_value(row_value, default_value)
       value.to_utf8
     end
 
+    # see https://developer.android.com/guide/topics/resources/string-resource#escaping_quotes
+    def escape_android_characters(value)
+      value.gsub!(/'/, "'" => "\\'") # \' should be the result...
+      value.gsub!(/&/, "&" => "&")
+      value.gsub!(/@/, "@" => "\@")
+      value
+    end
+
     def get_row_format(row_key, row_value, comment = nil, indentation = 0)
       entry = comment.to_s.empty? ? "" : "\n\t<!-- #{comment} -->\n"
       entry + "\t<string name=\"#{row_key}\">#{row_value}</string>\n"

test/babelish/test_csv2android.rb

@@ -69,4 +69,31 @@ def test_converting_with_basename
     # clean up
     system("rm -rf ./values-en")
   end
+
+  def test_android_character_escaping
+    converter = Babelish::CSV2Android.new(
+      "test/data/test_data_with_characters_that_need_escaping.csv",
+      { "English" => "en" },
+      output_basename: "escaped_strings"
+    )
+    converter.convert
+    exist = File.exist?("values-en/escaped_strings.xml")
+    assert exist, "the ouptut file does not exist"
+
+    output = File.read("values-en/escaped_strings.xml")
+    expected_output = File.read(
+      "test/data/test_data_with_characters_that_need_escaping.xml"
+    )
+
+    assert_equal expected_output, output
+
+    assert_true FileUtils.identical?(
+      "values-en/escaped_strings.xml",
+      "test/data/test_data_with_characters_that_need_escaping.xml"
+    )
+
+    # clean up
+    system("rm -rf ./values-en")
+
+  end
 end

test/data/test_data_with_characters_that_need_escaping.csv

@@ -0,0 +1,3 @@
+variables,English
+NEEDS_ESCAPING,?  '  @  <  &
+ANOTHER_STRING,hello

test/data/test_data_with_characters_that_need_escaping.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+	<string name="NEEDS_ESCAPING">\?  \'  \@  &lt;  &amp;</string>
+	<string name="ANOTHER_STRING">hello</string>
+</resources>