+func TestMemoryRunsAtMostEightBuilds(t *testing.T) {
+ summarizer := newFakeSummarizer()
+ summarizer.gate = make(chan struct{})
+ memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now, summarizer)
+ require.NoError(t, err)
+
+ defer func() {
+ require.NoError(t, memory.Close())
+ }()
+
+ for n := range 12 {
+ _, err = memory.Append("echo", longText(n))
+ require.NoError(t, err)
+ }
+
+ memory.mutex.Lock()
+ running := slices.Collect(maps.Keys(memory.queue.running))
+ memory.mutex.Unlock()
+ slices.SortFunc(running, func(a, b nodeKey) int {
+ return a.index - b.index
+ })
+ require.Equal(t, []nodeKey{{0, 0}, {0, 1}, {0, 2}, {0, 3}, {0, 4}, {0, 5}, {0, 6}, {0, 7}}, running)
+
+ require.Eventually(t, func() bool {
+ return summarizer.Active() == buildMax
+ }, 10*time.Second, time.Millisecond)
+
+ close(summarizer.gate)
+ require.NoError(t, memory.Wait(t.Context()))
+ require.Equal(t, buildMax, summarizer.peak)
+
+ for level, count := range []int{12, 6, 3, 1} {
+ for index := range count {
+ require.True(t, isBuilt(t, memory.tree, level, index), "node (%d, %d)", level, index)
+ }
+ }
+}
+
+func TestMemoryStartsALeafAfterFewerThanEightUnbuilt(t *testing.T) {
+ summarizer := newFakeSummarizer()
+ summarizer.SetFailing(true)
+ memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now, summarizer)
+ require.NoError(t, err)
+
+ defer func() {
+ require.NoError(t, memory.Close())
+ }()
+
+ for n := range 9 {
+ _, err = memory.Append("echo", longText(n))
+ require.NoError(t, err)
+ }
+
+ require.NoError(t, memory.Wait(t.Context()))
+ for _, task := range summarizer.Tasks() {
+ require.Less(t, task.Index, 8)
+ }
+
+ require.False(t, isBuilt(t, memory.tree, 0, 8))
+ summarizer.SetFailing(false)
+
+ _, err = memory.Append("user", "retry")
+ require.NoError(t, err)
+ require.NoError(t, memory.Wait(t.Context()))
+ require.True(t, isBuilt(t, memory.tree, 0, 8))
+ require.True(t, isBuilt(t, memory.tree, 3, 0))
+}
+
+func TestMemoryMergesAfterBothHalves(t *testing.T) {
+ summarizer := newFakeSummarizer()
+ memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now, summarizer)
+ require.NoError(t, err)
+
+ defer func() {
+ require.NoError(t, memory.Close())
+ }()
+
+ _, err = memory.Append("echo", longText(0))
+ require.NoError(t, err)
+ require.NoError(t, memory.Wait(t.Context()))
+
+ _, err = memory.Append("echo", longText(1))
+ require.NoError(t, err)
+ require.NoError(t, memory.Wait(t.Context()))
+ require.Len(t, summarizer.Tasks(), 3)
+
+ left := readNode(t, memory.tree, 0, 0)
+ right := readNode(t, memory.tree, 0, 1)
+ merge := summarizer.Tasks()[2]
+ require.Equal(t, []string{left.Text, right.Text}, merge.Input)
+ require.Equal(t, "<chat>\n0+1|"+left.Text+"\n1+1|"+right.Text+"\n</chat>", merge.Context)
+ require.True(t, isBuilt(t, memory.tree, 1, 0))
+}
+
+func TestMemoryRestartRestoresTheQueue(t *testing.T) {
+ root := t.TempDir()
+ clock := newTestClock()
+ summarizer := newFakeSummarizer()
+ summarizer.SetFailing(true)
+ memory, err := openMemory(t.Context(), root, clock.Now, summarizer)
+ require.NoError(t, err)
+
+ for n := range 4 {
+ _, err = memory.Append("echo", longText(n))
+ require.NoError(t, err)
+ }
+
+ require.NoError(t, memory.Wait(t.Context()))
+ require.NoError(t, memory.Close())
+
+ memory, err = openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
+ require.NoError(t, err)
+
+ defer func() {
+ require.NoError(t, memory.Close())
+ }()
+
+ require.NoError(t, memory.Wait(t.Context()))
+ require.True(t, isBuilt(t, memory.tree, 2, 0))
+}
+