Merge pull request #10 from gammazero/master
Get() accepts negative index.
Evan Huus authored 7 years ago
GitHub committed 7 years ago
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}
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// Get returns the element at index i in the queue. If the index is
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// invalid, the call will panic.
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// invalid, the call will panic. This method accepts both positive and
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// negative index values. Index 0 refers to the first element, and
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// index -1 refers to the last.
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func (q *Queue) Get(i int) interface{} {
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// If indexing backwards, convert to positive index.
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if i < 0 {
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i += q.count
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}
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if i < 0 || i >= q.count {
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panic("queue: Get() called with index out of range")
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}
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}
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}
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func TestQueueGetNegative(t *testing.T) {
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q := New()
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for i := 0; i < 1000; i++ {
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q.Add(i)
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for j := 1; j <= q.Length(); j++ {
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if q.Get(-j).(int) != q.Length()-j {
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t.Errorf("index %d doesn't contain %d", -j, q.Length()-j)
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}
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}
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}
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}
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func TestQueueGetOutOfRangePanics(t *testing.T) {
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q := New()
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q.Add(3)
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assertPanics(t, "should panic when negative index", func() {
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q.Get(-1)
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q.Get(-4)
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})
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assertPanics(t, "should panic when index greater than length", func() {
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