package torrent import ( "testing" "github.com/bradfitz/iter" qt "github.com/frankban/quicktest" pp "github.com/anacrolix/torrent/peer_protocol" ) func keysAsSlice(m map[Request]struct{}) (sl []Request) { for k := range m { sl = append(sl, k) } return } func makeTypicalRequests() map[Request]struct{} { m := make(map[Request]struct{}) for p := pp.Integer(0); p < 4; p++ { for c := pp.Integer(0); c < 16; c++ { m[Request{p, ChunkSpec{c * defaultChunkSize, defaultChunkSize}}] = struct{}{} } } return m } func TestLogExampleRequestMapOrdering(t *testing.T) { for k := range makeTypicalRequests() { t.Log(k) } } func TestRequestMapOrderingPersistent(t *testing.T) { m := makeTypicalRequests() // Shows that map order is persistent across separate range statements. qt.Assert(t, keysAsSlice(m), qt.ContentEquals, keysAsSlice(m)) } func TestRequestMapOrderAcrossInstances(t *testing.T) { // This shows that different map instances with the same contents can have the same range order. qt.Assert(t, keysAsSlice(makeTypicalRequests()), qt.ContentEquals, keysAsSlice(makeTypicalRequests())) } // Added for testing repeating loop iteration after shuffling in Peer.applyRequestState. func TestForLoopRepeatItem(t *testing.T) { t.Run("ExplicitLoopVar", func(t *testing.T) { once := false var seen []int for i := 0; i < 4; i++ { seen = append(seen, i) if !once && i == 2 { once = true i-- // Will i++ still run? continue } } // We can mutate i and it's observed by the loop. No special treatment of the loop var. qt.Assert(t, seen, qt.DeepEquals, []int{0, 1, 2, 2, 3}) }) t.Run("Range", func(t *testing.T) { once := false var seen []int for i := range iter.N(4) { seen = append(seen, i) if !once && i == 2 { once = true // Can we actually modify the next value of i produced by the range? i-- continue } } // Range ignores any mutation to i. qt.Assert(t, seen, qt.DeepEquals, []int{0, 1, 2, 3}) }) }