/
buffered_shared.rb
175 lines (138 loc) · 3.96 KB
/
buffered_shared.rb
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require_relative 'base_shared'
RSpec.shared_examples :channel_buffered_buffer do
it_behaves_like :channel_buffer
context '#initialize' do
it 'raises an exception if size <= 0' do
expect {
described_class.new(0)
}.to raise_error(ArgumentError)
end
end
context '#capacity' do
it 'returns the maximum capacity of the buffer' do
subject = described_class.new(10)
expect(subject.capacity).to eq 10
end
end
context '#size' do
it 'is 0 when first created' do
expect(subject.size).to eq 0
end
it 'returns the number of items in the buffer' do
fill = subject.capacity / 2
fill.times { subject.put(:foo) }
expect(subject.size).to eq fill
end
it 'is 0 when there are taking threads but no putting threads' do
t = Thread.new { subject.take }
t.join(0.1)
expect(subject.size).to eq 0
t.kill # cleanup
end
end
context '#empty?' do
it 'returns true when empty' do
subject = described_class.new(10)
expect(subject).to be_empty
end
end
context '#put' do
it 'enqueues the item when size > 0, not full, and not closed' do
subject.put(:foo)
expect(subject).to_not be_empty
end
it 'returns true when the item is put' do
expect(subject.put(:foo)).to be true
end
end
context '#offer' do
it 'enqueues the item immediately when not full and not closed' do
subject.offer(:foo)
expect(subject.take).to eq :foo
end
end
context '#take' do
it 'returns the first item when not empty' do
subject.put(:foo)
expect(subject.take).to eq :foo
end
it 'blocks until not empty' do
subject # initialize on this thread
bucket = Concurrent::AtomicReference.new(nil)
t = Thread.new do
bucket.value = subject.take
end
t.join(0.1)
before = bucket.value
subject.put(42)
t.join(0.1)
after = bucket.value
expect(before).to be nil
expect(after).to eq 42
expect(t.status).to be false
end
it 'returns Concurrent::NULL when closed and empty' do
subject.close
expect(subject.take).to eq Concurrent::NULL
end
end
context '#next' do
it 'blocks until not empty' do
subject # initialize on this thread
bucket = Concurrent::AtomicReference.new([])
t = Thread.new do
bucket.value = subject.next
end
t.join(0.1)
before = bucket.value
subject.put(42)
t.join(0.1)
after = bucket.value
expect(before).to eq []
expect(after.first).to eq 42
expect(after.last).to be true
expect(t.status).to be false
end
it 'returns <item>, true when there is only one item and not closed' do
subject.offer(42)
item, more = subject.next
expect(item).to eq 42
expect(more).to be true
end
it 'returns <item>, true when there are multiple items' do
subject.offer(:foo)
subject.offer(:bar)
subject.offer(:baz)
item1, more1 = subject.next
item2, more2 = subject.next
item3, more3 = subject.next
expect(item1).to eq :foo
expect(more1).to be true
expect(item2).to eq :bar
expect(more2).to be true
expect(item3).to eq :baz
expect(more3).to be true
end
it 'returns <item>, true when closed and last item' do
capacity = subject.capacity
expect(capacity).to be >= 1
capacity.times { subject.put(:foo) }
subject.close
capacity.times do
item, more = subject.next
expect(item).to eq :foo
expect(more).to be true
end
end
it 'returns Concurrent::NULL, false when closed and no items remain' do
capacity = subject.capacity
expect(capacity).to be >= 1
capacity.times { subject.put(:foo) }
subject.close
capacity.times { subject.next }
item, more = subject.next
expect(item).to eq Concurrent::NULL
expect(more).to be false
end
end
end