Add support for boolean values

including auto format, which will detect the strings 'true' and
'false' as boolean values.

README.md

@@ -36,8 +36,8 @@ Or install it yourself as:
 # Creates a new workbook and closes it at the end of the block
 Xlsxtream::Workbook.open('my_data.xlsx') do |xlsx|
   xlsx.write_worksheet 'Sheet1' do |sheet|
-    # Date, Time, DateTime and Numeric are properly mapped
-    sheet << [Date.today, 'hello', 'world', 42, 3.14159265359, 42**13]
+    # Boolean, Date, Time, DateTime and Numeric are properly mapped
+    sheet << [true, Date.today, 'hello', 'world', 42, 3.14159265359, 42**13]
   end
 end
 
@@ -71,10 +71,11 @@ end
 # appropriately. This is a convenient way to avoid an Excel-warning about
 # "Number stored as text". Dates and times must be in the ISO-8601 format and
 # numeric values must contain only numbers and an optional decimal separator.
+# The strings true and false are detected as boolean values.
 xlsx.write_worksheet('SheetWithAutoFormat', :auto_format => true) do |sheet|
   # these two rows will be identical in the xlsx-output
-  sheet << [11.85, DateTime.parse('2050-01-01T12:00'), Date.parse('1984-01-01')]
-  sheet << ['11.85', '2050-01-01T12:00', '1984-01-01']
+  sheet << [true, 11.85, DateTime.parse('2050-01-01T12:00'), Date.parse('1984-01-01')]
+  sheet << ['true', '11.85', '2050-01-01T12:00', '1984-01-01']
 end
 
 # Writes metadata and ZIP archive central directory

lib/xlsxtream/row.rb

@@ -13,6 +13,9 @@ class Row
     # ISO 8601 yyyy-mm-ddThh:mm:ss(.s)(Z|+hh:mm|-hh:mm)
     TIME_PATTERN = /\A[0-9]{4}-[0-9]{2}-[0-9]{2}T[0-9]{2}:[0-9]{2}(?::[0-9]{2}(?:\.[0-9]{1,9})?)?(?:Z|[+-][0-9]{2}:[0-9]{2})?\z/.freeze
 
+    TRUE_STRING = 'true'.freeze
+    FALSE_STRING = 'false'.freeze
+
     DATE_STYLE = 1
     TIME_STYLE = 2
 
@@ -38,6 +41,8 @@ def to_xml
         case value
         when Numeric
           xml << %Q{<c r="#{cid}" t="n"><v>#{value}</v></c>}
+        when TrueClass, FalseClass
+          xml << %Q{<c r="#{cid}" t="b"><v>#{value ? 1 : 0}</v></c>}
         when Time, DateTime
           xml << %Q{<c r="#{cid}" s="#{TIME_STYLE}"><v>#{time_to_oa_date(value)}</v></c>}
         when Date
@@ -65,6 +70,10 @@ def to_xml
     # Detects and casts numbers, date, time in text
     def auto_format(value)
       case value
+      when TRUE_STRING
+        true
+      when FALSE_STRING
+        false
       when NUMBER_PATTERN
         value.include?('.') ? value.to_f : value.to_i
       when DATE_PATTERN

test/xlsxtream/row_test.rb

@@ -24,6 +24,28 @@ def test_symbol_column
       assert_equal expected, actual
     end
 
+    def test_boolean_column
+      row = Row.new([true], 1)
+      actual = row.to_xml
+      expected = '<row r="1"><c r="A1" t="b"><v>1</v></c></row>'
+      assert_equal expected, actual
+      row = Row.new([false], 1)
+      actual = row.to_xml
+      expected = '<row r="1"><c r="A1" t="b"><v>0</v></c></row>'
+      assert_equal expected, actual
+    end
+
+    def test_text_boolean_column
+      row = Row.new(['true'], 1, :auto_format => true)
+      actual = row.to_xml
+      expected = '<row r="1"><c r="A1" t="b"><v>1</v></c></row>'
+      assert_equal expected, actual
+      row = Row.new(['false'], 1, :auto_format => true)
+      actual = row.to_xml
+      expected = '<row r="1"><c r="A1" t="b"><v>0</v></c></row>'
+      assert_equal expected, actual
+    end
+
     def test_integer_column
       row = Row.new([1], 1)
       actual = row.to_xml