package segments import ( "testing" "github.com/stretchr/testify/assert" ) func LengthIterFromSlice(ls []Length) LengthIter { return func() (Length, bool) { switch len(ls) { case 0: return -1, false default: l := ls[0] ls = ls[1:] return l, true } } } type ScanCallbackValue struct { Index int Extent } type collectExtents []ScanCallbackValue func (me *collectExtents) scanCallback(i int, e Extent) bool { *me = append(*me, ScanCallbackValue{ Index: i, Extent: e, }) return true } type newLocater func(LengthIter) Locater func assertLocate(t *testing.T, nl newLocater, ls []Length, needle Extent, firstExpectedIndex int, expectedExtents []Extent) { var actual collectExtents var expected collectExtents for i, e := range expectedExtents { expected.scanCallback(firstExpectedIndex+i, e) } nl(LengthIterFromSlice(ls))(needle, actual.scanCallback) assert.EqualValues(t, expected, actual) } func testLocater(t *testing.T, newLocater newLocater) { assertLocate(t, newLocater, []Length{1, 0, 2, 0, 3}, Extent{2, 2}, 2, []Extent{{1, 1}, {0, 0}, {0, 1}}) assertLocate(t, newLocater, []Length{1, 0, 2, 0, 3}, Extent{6, 2}, 2, []Extent{}) assertLocate(t, newLocater, []Length{1652, 1514, 1554, 1618, 1546, 129241752, 1537}, // 128737588 Extent{0, 16384}, 0, []Extent{ {0, 1652}, {0, 1514}, {0, 1554}, {0, 1618}, {0, 1546}, {0, 8500}}) assertLocate(t, newLocater, []Length{1652, 1514, 1554, 1618, 1546, 129241752, 1537, 1536, 1551}, // 128737588 Extent{129236992, 16384}, 5, []Extent{ {129229108, 12644}, {0, 1537}, {0, 1536}, {0, 667}}) } func TestScan(t *testing.T) { testLocater(t, LocaterFromLengthIter) } func TestIndex(t *testing.T) { testLocater(t, func(li LengthIter) Locater { return NewIndex(li).Locate }) }