2018-03-04 10:09:32 -05:00
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require_relative '../spec_helper'
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2017-05-07 08:04:49 -04:00
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describe 'Optional variable assignments' do
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describe 'using ||=' do
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describe 'using a single variable' do
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it 'assigns a new variable' do
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a ||= 10
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a.should == 10
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end
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it 're-assigns an existing variable set to false' do
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a = false
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a ||= 10
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a.should == 10
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end
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it 're-assigns an existing variable set to nil' do
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a = nil
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a ||= 10
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a.should == 10
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end
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it 'does not re-assign a variable with a truthy value' do
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a = 10
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a ||= 20
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a.should == 10
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end
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it 'does not evaluate the right side when not needed' do
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a = 10
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a ||= raise('should not be executed')
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a.should == 10
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end
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it 'does not re-assign a variable with a truthy value when using an inline rescue' do
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a = 10
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a ||= 20 rescue 30
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a.should == 10
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end
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end
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describe 'using a accessor' do
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before do
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klass = Class.new { attr_accessor :b }
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@a = klass.new
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end
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it 'assigns a new variable' do
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@a.b ||= 10
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@a.b.should == 10
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end
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it 're-assigns an existing variable set to false' do
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@a.b = false
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@a.b ||= 10
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@a.b.should == 10
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end
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it 're-assigns an existing variable set to nil' do
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@a.b = nil
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@a.b ||= 10
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@a.b.should == 10
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end
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it 'does not re-assign a variable with a truthy value' do
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@a.b = 10
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@a.b ||= 20
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@a.b.should == 10
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end
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it 'does not evaluate the right side when not needed' do
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@a.b = 10
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@a.b ||= raise('should not be executed')
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@a.b.should == 10
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end
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it 'does not re-assign a variable with a truthy value when using an inline rescue' do
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@a.b = 10
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@a.b ||= 20 rescue 30
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@a.b.should == 10
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end
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end
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end
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describe 'using &&=' do
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describe 'using a single variable' do
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it 'leaves new variable unassigned' do
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a &&= 10
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a.should == nil
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end
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it 'leaves false' do
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a = false
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a &&= 10
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a.should == false
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end
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it 'leaves nil' do
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a = nil
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a &&= 10
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a.should == nil
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end
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it 'does not evaluate the right side when not needed' do
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a = nil
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a &&= raise('should not be executed')
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a.should == nil
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end
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it 'does re-assign a variable with a truthy value' do
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a = 10
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a &&= 20
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a.should == 20
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end
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it 'does re-assign a variable with a truthy value when using an inline rescue' do
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a = 10
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a &&= 20 rescue 30
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a.should == 20
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end
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end
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describe 'using a single variable' do
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before do
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klass = Class.new { attr_accessor :b }
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@a = klass.new
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end
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it 'leaves new variable unassigned' do
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@a.b &&= 10
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@a.b.should == nil
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end
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it 'leaves false' do
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@a.b = false
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@a.b &&= 10
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@a.b.should == false
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end
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it 'leaves nil' do
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@a.b = nil
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@a.b &&= 10
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@a.b.should == nil
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end
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it 'does not evaluate the right side when not needed' do
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@a.b = nil
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@a.b &&= raise('should not be executed')
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@a.b.should == nil
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end
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it 'does re-assign a variable with a truthy value' do
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@a.b = 10
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@a.b &&= 20
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@a.b.should == 20
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end
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it 'does re-assign a variable with a truthy value when using an inline rescue' do
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@a.b = 10
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@a.b &&= 20 rescue 30
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@a.b.should == 20
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end
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end
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end
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describe 'using compunded constants' do
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before do
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Object.send(:remove_const, :A) if defined? Object::A
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end
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it 'with ||= assignments' do
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Object::A ||= 10
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Object::A.should == 10
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end
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it 'with ||= do not reassign' do
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Object::A = 20
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Object::A ||= 10
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Object::A.should == 20
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end
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it 'with &&= assignments' do
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Object::A = 20
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-> {
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Object::A &&= 10
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}.should complain(/already initialized constant/)
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Object::A.should == 10
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end
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2017-10-28 11:15:48 -04:00
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it 'with &&= assignments will fail with non-existent constants' do
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2017-05-07 08:04:49 -04:00
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lambda { Object::A &&= 10 }.should raise_error(NameError)
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end
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it 'with operator assignments' do
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Object::A = 20
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-> {
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Object::A += 10
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}.should complain(/already initialized constant/)
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Object::A.should == 30
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end
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2017-10-28 11:15:48 -04:00
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it 'with operator assignments will fail with non-existent constants' do
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2017-05-07 08:04:49 -04:00
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lambda { Object::A += 10 }.should raise_error(NameError)
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end
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end
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end
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