summaryrefslogtreecommitdiff
path: root/spec/ruby/core/kernel/Rational_spec.rb
diff options
context:
space:
mode:
Diffstat (limited to 'spec/ruby/core/kernel/Rational_spec.rb')
-rw-r--r--spec/ruby/core/kernel/Rational_spec.rb234
1 files changed, 232 insertions, 2 deletions
diff --git a/spec/ruby/core/kernel/Rational_spec.rb b/spec/ruby/core/kernel/Rational_spec.rb
index 2d1051db7f..b13ab4cf55 100644
--- a/spec/ruby/core/kernel/Rational_spec.rb
+++ b/spec/ruby/core/kernel/Rational_spec.rb
@@ -1,6 +1,236 @@
require_relative '../../spec_helper'
-require_relative '../../shared/rational/Rational'
+require_relative '../rational/fixtures/rational'
describe "Kernel.Rational" do
- it_behaves_like :kernel_Rational, :Rational
+ describe "passed Integer" do
+ # Guard against the Mathn library
+ guard -> { !defined?(Math.rsqrt) } do
+ it "returns a new Rational number with 1 as the denominator" do
+ Rational(1).should.eql?(Rational(1, 1))
+ Rational(-3).should.eql?(Rational(-3, 1))
+ Rational(bignum_value).should.eql?(Rational(bignum_value, 1))
+ end
+ end
+ end
+
+ describe "passed two integers" do
+ it "returns a new Rational number" do
+ rat = Rational(1, 2)
+ rat.numerator.should == 1
+ rat.denominator.should == 2
+ rat.should.instance_of?(Rational)
+
+ rat = Rational(-3, -5)
+ rat.numerator.should == 3
+ rat.denominator.should == 5
+ rat.should.instance_of?(Rational)
+
+ rat = Rational(bignum_value, 3)
+ rat.numerator.should == bignum_value
+ rat.denominator.should == 3
+ rat.should.instance_of?(Rational)
+ end
+
+ it "reduces the Rational" do
+ rat = Rational(2, 4)
+ rat.numerator.should == 1
+ rat.denominator.should == 2
+
+ rat = Rational(3, 9)
+ rat.numerator.should == 1
+ rat.denominator.should == 3
+ end
+ end
+
+ describe "when passed a String" do
+ it "converts the String to a Rational using the same method as String#to_r" do
+ r = Rational(13, 25)
+ s_r = ".52".to_r
+ r_s = Rational(".52")
+
+ r_s.should == r
+ r_s.should == s_r
+ end
+
+ it "scales the Rational value of the first argument by the Rational value of the second" do
+ Rational(".52", ".6").should == Rational(13, 15)
+ Rational(".52", "1.6").should == Rational(13, 40)
+ end
+
+ it "does not use the same method as Float#to_r" do
+ r = Rational(3, 5)
+ f_r = 0.6.to_r
+ r_s = Rational("0.6")
+
+ r_s.should == r
+ r_s.should_not == f_r
+ end
+ end
+
+ describe "when passed a Numeric" do
+ it "calls #to_r to convert the first argument to a Rational" do
+ num = RationalSpecs::SubNumeric.new(2)
+
+ Rational(num).should == Rational(2)
+ end
+ end
+
+ describe "when passed a Complex" do
+ context "[Complex]" do
+ it "returns a Rational from the real part if the imaginary part is 0" do
+ Rational(Complex(1, 0)).should == Rational(1)
+ end
+
+ it "raises a RangeError if the imaginary part is not 0" do
+ -> { Rational(Complex(1, 2)) }.should.raise(RangeError, "can't convert 1+2i into Rational")
+ end
+ end
+
+ context "[Numeric, Complex]" do
+ it "uses the real part if the imaginary part is 0" do
+ Rational(1, Complex(2, 0)).should == Rational(1, 2)
+ end
+
+ it "divides a numerator by the Complex denominator if the imaginary part is not 0" do
+ Rational(1, Complex(2, 1)).should == Complex(2/5r, -1/5r)
+ end
+ end
+ end
+
+ context "when passed neither a Numeric nor a String" do
+ it "converts to Rational with #to_r method" do
+ obj = Object.new
+ def obj.to_r; 1/2r; end
+
+ Rational(obj).should == 1/2r
+ end
+
+ it "tries to convert to Integer with #to_int method if it does not respond to #to_r" do
+ obj = Object.new
+ def obj.to_int; 1; end
+
+ Rational(obj).should == 1r
+ end
+
+ it "raises TypeError if it neither responds to #to_r nor #to_int method" do
+ -> { Rational([]) }.should.raise(TypeError, "can't convert Array into Rational")
+ -> { Rational({}) }.should.raise(TypeError, "can't convert Hash into Rational")
+ -> { Rational(nil) }.should.raise(TypeError, "can't convert nil into Rational")
+ end
+
+ it "swallows exception raised in #to_int method" do
+ object = Object.new
+ def object.to_int() raise NoMethodError; end
+
+ -> { Rational(object) }.should.raise(TypeError)
+ -> { Rational(object, 1) }.should.raise(TypeError)
+ -> { Rational(1, object) }.should.raise(TypeError)
+ end
+
+ it "raises TypeError if #to_r does not return Rational" do
+ obj = Object.new
+ def obj.to_r; []; end
+
+ -> { Rational(obj) }.should raise_consistent_error(TypeError, "can't convert Object into Rational (Object#to_r gives Array)")
+ end
+ end
+
+ it "raises a ZeroDivisionError if the second argument is 0" do
+ -> { Rational(1, 0) }.should.raise(ZeroDivisionError, "divided by 0")
+ -> { Rational(1, 0.0) }.should.raise(ZeroDivisionError, "divided by 0")
+ end
+
+ it "raises a TypeError if the first argument is nil" do
+ -> { Rational(nil) }.should.raise(TypeError, "can't convert nil into Rational")
+ end
+
+ it "raises a TypeError if the second argument is nil" do
+ -> { Rational(1, nil) }.should.raise(TypeError, "can't convert nil into Rational")
+ end
+
+ it "raises a TypeError if the first argument is a Symbol" do
+ -> { Rational(:sym) }.should.raise(TypeError)
+ end
+
+ it "raises a TypeError if the second argument is a Symbol" do
+ -> { Rational(1, :sym) }.should.raise(TypeError)
+ end
+
+ describe "when passed exception: false" do
+ describe "and [non-Numeric]" do
+ it "swallows an error" do
+ Rational(:sym, exception: false).should == nil
+ Rational("abc", exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_r" do
+ obj = Object.new
+ def obj.to_r; raise; end
+ Rational(obj, exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_int" do
+ obj = Object.new
+ def obj.to_int; raise; end
+ Rational(obj, exception: false).should == nil
+ end
+ end
+
+ describe "and [non-Numeric, Numeric]" do
+ it "swallows an error" do
+ Rational(:sym, 1, exception: false).should == nil
+ Rational("abc", 1, exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_r" do
+ obj = Object.new
+ def obj.to_r; raise; end
+ Rational(obj, 1, exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_int" do
+ obj = Object.new
+ def obj.to_int; raise; end
+ Rational(obj, 1, exception: false).should == nil
+ end
+ end
+
+ describe "and [anything, non-Numeric]" do
+ it "swallows an error" do
+ Rational(:sym, :sym, exception: false).should == nil
+ Rational("abc", :sym, exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_r" do
+ obj = Object.new
+ def obj.to_r; raise; end
+ Rational(obj, obj, exception: false).should == nil
+ end
+
+ it "swallows an exception raised in #to_int" do
+ obj = Object.new
+ def obj.to_int; raise; end
+ Rational(obj, obj, exception: false).should == nil
+ end
+ end
+
+ describe "and non-Numeric String arguments" do
+ it "swallows an error" do
+ Rational("a", "b", exception: false).should == nil
+ Rational("a", 0, exception: false).should == nil
+ Rational(0, "b", exception: false).should == nil
+ end
+ end
+
+ describe "and nil arguments" do
+ it "swallows an error" do
+ Rational(nil, exception: false).should == nil
+ Rational(nil, nil, exception: false).should == nil
+ end
+ end
+ end
+
+ it "freezes its result" do
+ Rational(1).frozen?.should == true
+ end
end