File: //usr/local/rvm/src/ruby-2.5.9/spec/ruby/core/string/start_with_spec.rb
# -*- encoding: utf-8 -*-
require File.expand_path('../../../spec_helper', __FILE__)
require File.expand_path('../fixtures/classes.rb', __FILE__)
describe "String#start_with?" do
it "returns true only if beginning match" do
s = "hello"
s.start_with?('h').should be_true
s.start_with?('hel').should be_true
s.start_with?('el').should be_false
end
it "returns true only if any beginning match" do
"hello".start_with?('x', 'y', 'he', 'z').should be_true
end
it "returns true if the search string is empty" do
"hello".start_with?("").should be_true
"".start_with?("").should be_true
end
it "converts its argument using :to_str" do
s = "hello"
find = mock('h')
find.should_receive(:to_str).and_return("h")
s.start_with?(find).should be_true
end
it "ignores arguments not convertible to string" do
"hello".start_with?().should be_false
lambda { "hello".start_with?(1) }.should raise_error(TypeError)
lambda { "hello".start_with?(["h"]) }.should raise_error(TypeError)
lambda { "hello".start_with?(1, nil, "h") }.should raise_error(TypeError)
end
it "uses only the needed arguments" do
find = mock('h')
find.should_not_receive(:to_str)
"hello".start_with?("h",find).should be_true
end
it "works for multibyte strings" do
"céréale".start_with?("cér").should be_true
end
end