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require File.expand_path('../../../spec_helper', __FILE__)
ruby_version_is "1.9" do
describe "String#to_r" do
it "returns a Rational object" do
String.new.to_r.should be_an_instance_of(Rational)
end
it "returns (0/1) for the empty String" do
"".to_r.should == Rational(0, 1)
end
it "returns (n/1) for a String starting with a decimal _n_" do
"2".to_r.should == Rational(2, 1)
"1765".to_r.should == Rational(1765, 1)
end
it "ignores trailing characters" do
"2 foo".to_r.should == Rational(2, 1)
"1765, ".to_r.should == Rational(1765, 1)
end
it "ignores leading spaces" do
" 2".to_r.should == Rational(2, 1)
" 1765, ".to_r.should == Rational(1765, 1)
end
it "does not ignore arbitrary, non-numeric leading characters" do
"The rational form of 33 is...".to_r.should_not == Rational(33, 1)
"a1765, ".to_r.should_not == Rational(1765, 1)
end
it "treats leading hypens as minus signs" do
"-20".to_r.should == Rational(-20, 1)
end
it "does not treat a leading period without a numeric prefix as a decimal point" do
".9".to_r.should_not == Rational(8106479329266893, 9007199254740992)
end
it "understands decimal points" do
"3.33".to_r.should == Rational(333, 100)
"-3.33".to_r.should == Rational(-333, 100)
end
it "ignores underscores between numbers" do
"190_22".to_r.should == Rational(19022, 1)
"-190_22.7".to_r.should == Rational(-190227, 10)
end
it "understands a forward slash as separating the numerator from the denominator" do
"20/3".to_r.should == Rational(20, 3)
" -19.10/3".to_r.should == Rational(-191, 30)
end
it "returns (0/1) for Strings it can't parse" do
"glark".to_r.should == Rational(0,1)
end
end
end
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