Merge branch 'master' into serializedAttributes

2 files changed, 14 insertions, 2 deletions

diff --git a/lib/axlsx/util/constants.rb b/lib/axlsx/util/constants.rb
index 4697bb3a..5ef3ece1 100644
--- a/lib/axlsx/util/constants.rb
+++ b/lib/axlsx/util/constants.rb
@@ -413,4 +413,16 @@ module Axlsx
 
   # Numeric recognition
   NUMERIC_REGEX = /\A[+-]?\d+?\Z/.freeze
+
+  # Leading characters that indicate a formula.
+  # See: https://owasp.org/www-community/attacks/CSV_Injection
+  FORMULA_PREFIX = '='
+
+  # Leading characters that indicate an array formula.
+  ARRAY_FORMULA_PREFIX = '{='
+
+  # Trailing character that indicates an array formula.
+  ARRAY_FORMULA_SUFFIX = '}'
+
+  BOOLEAN_VALUES = [true, false].freeze
 end
diff --git a/lib/axlsx/util/validators.rb b/lib/axlsx/util/validators.rb
index 0004f51a..e9cf13b6 100644
--- a/lib/axlsx/util/validators.rb
+++ b/lib/axlsx/util/validators.rb
@@ -106,8 +106,8 @@ module Axlsx
     DataTypeValidator.validate :signed_int, Integer, v
   end
 
-  VALID_BOOLEAN_CLASSES = [String, Integer, Symbol, TrueClass, FalseClass].freeze
-  VALID_BOOLEAN_VALUES = [0, 1, 'true', 'false', :true, :false, true, false, '0', '1'].freeze
+  VALID_BOOLEAN_CLASSES = [TrueClass, FalseClass, Integer, String, Symbol].freeze
+  VALID_BOOLEAN_VALUES = [true, false, 1, 0, '1', '0', 'true', 'false', :true, :false].freeze
   BOOLEAN_VALIDATOR = lambda { |arg| VALID_BOOLEAN_VALUES.include?(arg) }
 
   # Requires that the value is a form that can be evaluated as a boolean in an xml document.