Ticket #8626: round_with_precision.diff

activesupport/test/core_ext/float_test.rb

@@ +1 @@
+require File.dirname(__FILE__) + '/../abstract_unit'
+
+class FloatTests < Test::Unit::TestCase
+  def test_round
+    @float = 1.337
+    assert_equal 1,    @float.round
+    assert_equal 1,    @float.round(0)
+    assert_equal 1,    @float.round(nil)
+    assert_equal 1.3,  @float.round(1)
+    assert_equal 1.3,  @float.round('1')
+    assert_equal 1.3,  @float.round(1.0)
+    assert_equal 1.34, @float.round(2)
+  end
+end

activesupport/lib/active_support/core_ext/float.rb

@@ +1 @@
+class Float
+  alias_method :round_without_precision, :round
+
+  # Rounds the float, optionally with a specified precision.
+  #
+  #   x = 1.337
+  #   x.round    # => 1
+  #   x.round(1) # => 1.3
+  #   x.round(2) # => 1.34
+  def round(precision = nil)
+    precision = precision.to_i
+    if precision == 0
+      round_without_precision
+    else
+      (self * (10 ** precision)).round / (10 ** precision).to_f
+    end 
+  end
+end