Fixed the behaviour of Table when the specified width exceeds the tot…

…al column width

lib/terminal-table/table.rb

@@ -166,7 +166,7 @@ def additional_column_widths
       return [] if style.width.nil?
       spacing = style.width - columns_width
       if spacing < 0
-        raise "Table width exceeds wanted width of #{wanted} characters."
+        raise "Table width exceeds wanted width of #{style.width} characters."
       else
         per_col = spacing / number_of_columns
         arr = (1...number_of_columns).to_a.map { |i| per_col }

spec/table_spec.rb

@@ -173,6 +173,16 @@ module Terminal
       EOF
     end
 
+    it "should raise an error if the table width exceeds style width" do
+      @table.headings = ['Char', 'Num']
+      @table << ['a', 1]
+      @table << ['b', 2]
+      @table << ['c', 3]
+      @table << ['d', 'x' * 22]
+      @table.style.width = 21
+      expect { @table.render }.to raise_error "Table width exceeds wanted width of 21 characters."
+    end
+
     it "should render title properly" do
       @table.title = "Title"
       @table.headings = ['Char', 'Num']