13 files changed, 213 insertions, 0 deletions
diff --git a/spec/ruby/library/mathn/bignum/exponent_spec.rb b/spec/ruby/library/mathn/bignum/exponent_spec.rb
new file mode 100644
index 0000000000..758c2f27fd
--- /dev/null
+++ b/spec/ruby/library/mathn/bignum/exponent_spec.rb
@@ -0,0 +1,21 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Bignum#**" do
+    before :each do
+      @bignum = bignum_value(47)
+    end
+
+    it "returns self raised to other (positive) power" do
+      (@bignum ** 4).should == 7237005577332262361485077344629993318496048279512298547155833600056910050625
+      (@bignum ** 1.2).should be_close(57262152889751597425762.57804, TOLERANCE)
+    end
+
+    it "returns a complex number when negative and raised to a fractional power" do
+      ((-@bignum) ** (1/3)).should be_close(Complex(1048576,1816186.907597341), TOLERANCE)
+      ((-@bignum) ** (1.0/3)).should be_close(Complex(1048576,1816186.907597341), TOLERANCE)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/complex/Complex_spec.rb b/spec/ruby/library/mathn/complex/Complex_spec.rb
new file mode 100644
index 0000000000..93bb3f0c60
--- /dev/null
+++ b/spec/ruby/library/mathn/complex/Complex_spec.rb
@@ -0,0 +1,14 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Kernel#Complex" do
+    it "returns an Integer if imaginary part is 0" do
+      Complex(42,0).should == 42
+      Complex(42,0).should be_kind_of(Fixnum)
+      Complex(bignum_value,0).should == bignum_value
+      Complex(bignum_value,0).should be_kind_of(Bignum)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/fixnum/exponent_spec.rb b/spec/ruby/library/mathn/fixnum/exponent_spec.rb
new file mode 100644
index 0000000000..d72bc5aa00
--- /dev/null
+++ b/spec/ruby/library/mathn/fixnum/exponent_spec.rb
@@ -0,0 +1,17 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Fixnum#**" do
+    it "returns self raised to other (positive) power" do
+      (2 ** 4).should == 16
+      (2 ** 1.2).should be_close(2.2973967, TOLERANCE)
+    end
+
+    it "returns a complex number when negative and raised to a fractional power" do
+      ((-8) ** (1/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
+      ((-8) ** (1.0/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/float/exponent_spec.rb b/spec/ruby/library/mathn/float/exponent_spec.rb
new file mode 100644
index 0000000000..55af43ce5b
--- /dev/null
+++ b/spec/ruby/library/mathn/float/exponent_spec.rb
@@ -0,0 +1,17 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Float#**" do
+    it "returns self raised to other (positive) power" do
+      (2.0 ** 4).should == 16.0
+      (2.0 ** 1.2).should be_close(2.2973967, TOLERANCE)
+    end
+
+    it "returns a complex number when negative and raised to a fractional power" do
+      ((-8.0) ** (1/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
+      ((-8.0) ** (1.0/3)).should be_close(Complex(1, 1.73205), TOLERANCE)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/integer/from_prime_division_spec.rb b/spec/ruby/library/mathn/integer/from_prime_division_spec.rb
new file mode 100644
index 0000000000..47aaf47797
--- /dev/null
+++ b/spec/ruby/library/mathn/integer/from_prime_division_spec.rb
@@ -0,0 +1,11 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Integer.from_prime_division" do
+    it "reverses a prime factorization of an integer" do
+      Integer.from_prime_division([[2, 1], [3, 2], [7, 1]]).should == 126
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/integer/prime_division_spec.rb b/spec/ruby/library/mathn/integer/prime_division_spec.rb
new file mode 100644
index 0000000000..63a5c39733
--- /dev/null
+++ b/spec/ruby/library/mathn/integer/prime_division_spec.rb
@@ -0,0 +1,21 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Integer#prime_division" do
+    it "performs a prime factorization of a positive integer" do
+      100.prime_division.should == [[2, 2], [5, 2]]
+    end
+
+    # Proper handling of negative integers has been added to MRI trunk
+    # in revision 24091. Prior to that, all versions of MRI returned nonsense.
+    it "performs a prime factorization of a negative integer" do
+      -26.prime_division.should == [[-1, 1], [2, 1], [13, 1]]
+    end
+
+    it "raises a ZeroDivisionError when is called on zero" do
+      lambda { 0.prime_division }.should raise_error(ZeroDivisionError)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/math/fixtures/classes.rb b/spec/ruby/library/mathn/math/fixtures/classes.rb
new file mode 100644
index 0000000000..024732fa7a
--- /dev/null
+++ b/spec/ruby/library/mathn/math/fixtures/classes.rb
@@ -0,0 +1,3 @@
+class IncludesMath
+  include Math
+end
diff --git a/spec/ruby/library/mathn/math/rsqrt_spec.rb b/spec/ruby/library/mathn/math/rsqrt_spec.rb
new file mode 100644
index 0000000000..a49efa6ff9
--- /dev/null
+++ b/spec/ruby/library/mathn/math/rsqrt_spec.rb
@@ -0,0 +1,17 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require File.expand_path('../shared/rsqrt', __FILE__)
+
+  describe "Math#rsqrt" do
+    it_behaves_like :mathn_math_rsqrt, :_, IncludesMath.new
+
+    it "is a private instance method" do
+      IncludesMath.should have_private_instance_method(:rsqrt)
+    end
+  end
+
+  describe "Math.rsqrt" do
+    it_behaves_like :mathn_math_rsqrt, :_, Math
+  end
+end
diff --git a/spec/ruby/library/mathn/math/shared/rsqrt.rb b/spec/ruby/library/mathn/math/shared/rsqrt.rb
new file mode 100644
index 0000000000..68e2f7d02f
--- /dev/null
+++ b/spec/ruby/library/mathn/math/shared/rsqrt.rb
@@ -0,0 +1,21 @@
+require 'mathn'
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :mathn_math_rsqrt, shared: true do
+  it "returns the square root for Rational numbers" do
+    @object.send(:rsqrt, Rational(9, 25)).should == Rational(3, 5)
+    @object.send(:rsqrt, 16/64).should == Rational(1, 2)
+  end
+
+  it "returns the square root for positive numbers" do
+    @object.send(:rsqrt, 1).should == 1
+    @object.send(:rsqrt, 4.0).should == 2.0
+    @object.send(:rsqrt, 12.34).should == Math.sqrt!(12.34)
+  end
+
+  it "raises an Math::DomainError if the argument is a negative number" do
+    lambda { @object.send(:rsqrt, -1) }.should raise_error(Math::DomainError)
+    lambda { @object.send(:rsqrt, -4.0) }.should raise_error(Math::DomainError)
+    lambda { @object.send(:rsqrt, -16/64) }.should raise_error(Math::DomainError)
+  end
+end
diff --git a/spec/ruby/library/mathn/math/shared/sqrt.rb b/spec/ruby/library/mathn/math/shared/sqrt.rb
new file mode 100644
index 0000000000..6aab25fc5d
--- /dev/null
+++ b/spec/ruby/library/mathn/math/shared/sqrt.rb
@@ -0,0 +1,25 @@
+require 'mathn'
+require File.expand_path('../../fixtures/classes', __FILE__)
+
+describe :mathn_math_sqrt, shared: true do
+  it "returns the square root for Rational numbers" do
+    @object.send(:sqrt, Rational(9, 25)).should == Rational(3, 5)
+    @object.send(:sqrt, 16/64).should == Rational(1, 2)
+  end
+
+  it "returns the square root for Complex numbers" do
+    @object.send(:sqrt, Complex(1, 0)).should == 1
+  end
+
+  it "returns the square root for positive numbers" do
+    @object.send(:sqrt, 1).should == 1
+    @object.send(:sqrt, 4.0).should == 2.0
+    @object.send(:sqrt, 12.34).should == Math.sqrt!(12.34)
+  end
+
+  it "returns the square root for negative numbers" do
+    @object.send(:sqrt, -9).should == Complex(0, 3)
+    @object.send(:sqrt, -5.29).should == Complex(0, 2.3)
+    @object.send(:sqrt, -16/64).should == Complex(0, 1/2)
+  end
+end
diff --git a/spec/ruby/library/mathn/math/sqrt_spec.rb b/spec/ruby/library/mathn/math/sqrt_spec.rb
new file mode 100644
index 0000000000..b723360891
--- /dev/null
+++ b/spec/ruby/library/mathn/math/sqrt_spec.rb
@@ -0,0 +1,17 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require File.expand_path('../shared/sqrt', __FILE__)
+
+  describe "Math#rsqrt" do
+    it_behaves_like :mathn_math_sqrt, :_, IncludesMath.new
+
+    it "is a private instance method" do
+      IncludesMath.should have_private_instance_method(:sqrt)
+    end
+  end
+
+  describe "Math.rsqrt" do
+    it_behaves_like :mathn_math_sqrt, :_, Math
+  end
+end
diff --git a/spec/ruby/library/mathn/rational/Rational_spec.rb b/spec/ruby/library/mathn/rational/Rational_spec.rb
new file mode 100644
index 0000000000..71433529c5
--- /dev/null
+++ b/spec/ruby/library/mathn/rational/Rational_spec.rb
@@ -0,0 +1,14 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Kernel#Rational" do
+    it "returns an Integer if denominator divides numerator evenly" do
+      Rational(42,6).should == 7
+      Rational(42,6).should be_kind_of(Fixnum)
+      Rational(bignum_value,1).should == bignum_value
+      Rational(bignum_value,1).should be_kind_of(Bignum)
+    end
+  end
+end
diff --git a/spec/ruby/library/mathn/rational/inspect_spec.rb b/spec/ruby/library/mathn/rational/inspect_spec.rb
new file mode 100644
index 0000000000..ce1205faaa
--- /dev/null
+++ b/spec/ruby/library/mathn/rational/inspect_spec.rb
@@ -0,0 +1,15 @@
+require File.expand_path('../../../../spec_helper', __FILE__)
+
+ruby_version_is ''...'2.5' do
+  require 'mathn'
+
+  describe "Rational#inspect" do
+    it "returns a string representation of self" do
+      Rational(3, 4).inspect.should == "(3/4)"
+      Rational(-5, 8).inspect.should == "(-5/8)"
+      Rational(-1, -2).inspect.should == "(1/2)"
+      Rational(0, 2).inspect.should == "0"
+      Rational(bignum_value, 1).inspect.should == "#{bignum_value}"
+    end
+  end
+end