Limit number values to a sensible range

Number values are now limited to a maximum of `Float::MAX` and a minimum
of negative `Float::MAX`.

Internally, `Integer` is now used for numbers parsed as the "integer"
type (as defined in the spec), while `Float` is used for numbers parsed
as the "number" type.

Fixes #10

lib/crass/tokenizer.rb

@@ -429,27 +429,36 @@ def consume_number
     # 4.3.3. http://dev.w3.org/csswg/css-syntax/#consume-a-numeric-token
     def consume_numeric
       number = consume_number
+      repr = number[0]
+      value = number[1]
+      type = number[2]
+
+      if type == :integer
+        value = value.to_i
+      else
+        value = value.to_f
+      end
 
       if start_identifier?(@s.peek(3))
         create_token(:dimension,
-          :repr  => number[0],
-          :type  => number[2],
-          :unit  => consume_name,
-          :value => number[1])
+          :repr => repr,
+          :type => type,
+          :unit => consume_name,
+          :value => value)
 
       elsif @s.peek == '%'
         @s.consume
 
         create_token(:percentage,
-          :repr  => number[0],
-          :type  => number[2],
-          :value => number[1])
+          :repr => repr,
+          :type => type,
+          :value => value)
 
       else
         create_token(:number,
-          :repr  => number[0],
-          :type  => number[2],
-          :value => number[1])
+          :repr => repr,
+          :type => type,
+          :value => value)
       end
     end
 
@@ -588,9 +597,19 @@ def convert_string_to_number(str)
       t = matches[:exponent_sign] == '-' ? -1 : 1
       e = matches[:exponent].to_i
 
-      # I know this looks nutty, but it's exactly what's defined in the spec,
-      # and it works.
-      s * (i + f * 10**-d) * 10**(t * e)
+      # I know this formula looks nutty, but it's exactly what's defined in the
+      # spec, and it works.
+      value = s * (i + f * 10**-d) * 10**(t * e)
+
+      # Maximum and minimum values aren't defined in the spec, but are enforced
+      # here for sanity.
+      if value > Float::MAX
+        value = Float::MAX
+      elsif value < -Float::MAX
+        value = -Float::MAX
+      end
+
+      value
     end
 
     # Creates and returns a new token with the given _properties_.

test/shared/parse_rules.rb

@@ -313,6 +313,155 @@
     end
   end
 
+  # https://github.com/rgrove/crass/issues/10
+  it 'should limit number values to a maximum of `Float::MAX`' do
+    tree = parse("div { height: 5e99999 }")
+
+    assert_equal([
+      {:node=>:style_rule,
+        :selector=>
+         {:node=>:selector,
+          :value=>"div",
+          :tokens=>
+           [{:node=>:ident, :pos=>0, :raw=>"div", :value=>"div"},
+            {:node=>:whitespace, :pos=>3, :raw=>" "}]},
+        :children=>
+         [{:node=>:whitespace, :pos=>5, :raw=>" "},
+          {:node=>:property,
+           :name=>"height",
+           :value=>"5e99999",
+           :children=>
+            [{:node=>:whitespace, :pos=>13, :raw=>" "},
+             {:node=>:number,
+              :pos=>14,
+              :raw=>"5e99999",
+              :repr=>"5e99999",
+              :type=>:number,
+              :value=>1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>21, :raw=>" "}],
+           :important=>false,
+           :tokens=>
+            [{:node=>:ident, :pos=>6, :raw=>"height", :value=>"height"},
+             {:node=>:colon, :pos=>12, :raw=>":"},
+             {:node=>:whitespace, :pos=>13, :raw=>" "},
+             {:node=>:number,
+              :pos=>14,
+              :raw=>"5e99999",
+              :repr=>"5e99999",
+              :type=>:number,
+              :value=>1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>21, :raw=>" "}]}]}
+    ], tree)
+  end
+
+  # https://github.com/rgrove/crass/issues/10
+  it 'should limit number values to a minimum of `-Float::MAX`' do
+    tree = parse("div { margin: -5e99999 }")
+
+    assert_equal([
+      {:node=>:style_rule,
+        :selector=>
+         {:node=>:selector,
+          :value=>"div",
+          :tokens=>
+           [{:node=>:ident, :pos=>0, :raw=>"div", :value=>"div"},
+            {:node=>:whitespace, :pos=>3, :raw=>" "}]},
+        :children=>
+         [{:node=>:whitespace, :pos=>5, :raw=>" "},
+          {:node=>:property,
+           :name=>"margin",
+           :value=>"-5e99999",
+           :children=>
+            [{:node=>:whitespace, :pos=>13, :raw=>" "},
+             {:node=>:number,
+              :pos=>14,
+              :raw=>"-5e99999",
+              :repr=>"-5e99999",
+              :type=>:number,
+              :value=>-1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>22, :raw=>" "}],
+           :important=>false,
+           :tokens=>
+            [{:node=>:ident, :pos=>6, :raw=>"margin", :value=>"margin"},
+             {:node=>:colon, :pos=>12, :raw=>":"},
+             {:node=>:whitespace, :pos=>13, :raw=>" "},
+             {:node=>:number,
+              :pos=>14,
+              :raw=>"-5e99999",
+              :repr=>"-5e99999",
+              :type=>:number,
+              :value=>-1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>22, :raw=>" "}]}]}
+    ], tree)
+  end
+
+  # https://github.com/rgrove/crass/issues/10
+  it 'should parse a class selector that looks like an exponent' do
+    tree = parse("p.5e1367490fa5f06927cafe55msonormal {}")
+
+    assert_equal([
+      {:node=>:style_rule,
+        :selector=>
+         {:node=>:selector,
+          :value=>"p.5e1367490fa5f06927cafe55msonormal",
+          :tokens=>
+           [{:node=>:ident, :pos=>0, :raw=>"p", :value=>"p"},
+            {:node=>:dimension,
+             :pos=>1,
+             :raw=>".5e1367490fa5f06927cafe55msonormal",
+             :repr=>".5e1367490",
+             :type=>:number,
+             :unit=>"fa5f06927cafe55msonormal",
+             :value=>1.7976931348623157e+308},
+            {:node=>:whitespace, :pos=>35, :raw=>" "}]},
+        :children=>[]}
+    ], tree)
+  end
+
+  # https://github.com/rgrove/crass/issues/10
+  it 'should parse a property value that looks like an exponent' do
+    tree = parse("p { mso-style-name:5e1367490fa5f06927cafe55msonormal }")
+
+    assert_equal([
+      {:node=>:style_rule,
+        :selector=>
+         {:node=>:selector,
+          :value=>"p",
+          :tokens=>
+           [{:node=>:ident, :pos=>0, :raw=>"p", :value=>"p"},
+            {:node=>:whitespace, :pos=>1, :raw=>" "}]},
+        :children=>
+         [{:node=>:whitespace, :pos=>3, :raw=>" "},
+          {:node=>:property,
+           :name=>"mso-style-name",
+           :value=>"5e1367490fa5f06927cafe55msonormal",
+           :children=>
+            [{:node=>:dimension,
+              :pos=>19,
+              :raw=>"5e1367490fa5f06927cafe55msonormal",
+              :repr=>"5e1367490",
+              :type=>:number,
+              :unit=>"fa5f06927cafe55msonormal",
+              :value=>1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>52, :raw=>" "}],
+           :important=>false,
+           :tokens=>
+            [{:node=>:ident,
+              :pos=>4,
+              :raw=>"mso-style-name",
+              :value=>"mso-style-name"},
+             {:node=>:colon, :pos=>18, :raw=>":"},
+             {:node=>:dimension,
+              :pos=>19,
+              :raw=>"5e1367490fa5f06927cafe55msonormal",
+              :repr=>"5e1367490",
+              :type=>:number,
+              :unit=>"fa5f06927cafe55msonormal",
+              :value=>1.7976931348623157e+308},
+             {:node=>:whitespace, :pos=>52, :raw=>" "}]}]}
+    ], tree)
+  end
+
   it 'should parse property values containing functions' do
     tree = parse("p:before { content: a\\ttr(data-foo) \" \"; }")