X-Git-Url: http://git.giacomolli.uk/onechat/blobdiff_plain/9f17bfb1173524553fff5301b0664267b430e6e3..b2873a2a0bf8b0ba648aebac51759e5fed89a2e2:/memory_test.go

diff --git a/memory_test.go b/memory_test.go
index b5bddb0..7b39795 100644
--- a/memory_test.go
+++ b/memory_test.go
@@ -1,10 +1,18 @@
 package main
 
 import (
+	"context"
+	"errors"
 	"fmt"
+	"maps"
 	"os"
 	"path/filepath"
+	"slices"
+	"strings"
+	"sync"
 	"testing"
+	"time"
+	"unicode/utf8"
 
 	"github.com/stretchr/testify/require"
 )
@@ -12,23 +20,26 @@ import (
 func TestMemoryRestartLoadsTheSameView(t *testing.T) {
 	root := t.TempDir()
 	clock := newTestClock()
-	memory, err := openMemory(t.Context(), root, clock.Now)
+	memory, err := openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	memory.chat.high = 200
 	memory.chat.low = 100
+	memory.cview.high = 80
+	memory.cview.low = 40
 	for n := range 100 {
 		_, err = memory.Append("user", fmt.Sprint(n))
 		require.NoError(t, err)
 	}
 
 	view := memory.View()
+	context := memory.Context(0, 100)
 	saved, err := os.ReadFile(filepath.Join(root, "view.json"))
 	require.NoError(t, err)
 	require.Less(t, len(memory.chat.lines), 100)
 	require.NoError(t, memory.Close())
 
-	memory, err = openMemory(t.Context(), root, clock.Now)
+	memory, err = openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	defer func() {
@@ -36,14 +47,192 @@ func TestMemoryRestartLoadsTheSameView(t *testing.T) {
 	}()
 
 	require.Equal(t, view, memory.View())
+	require.Equal(t, context, memory.Context(0, 100))
 
 	loaded, err := os.ReadFile(filepath.Join(root, "view.json"))
 	require.NoError(t, err)
 	require.Equal(t, saved, loaded)
 }
 
+func TestMemoryOpensAfterACrashBeforeTheViewSave(t *testing.T) {
+	root := t.TempDir()
+	clock := newTestClock()
+	memory, err := openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
+	require.NoError(t, err)
+
+	_, err = memory.Append("user", "first")
+	require.NoError(t, err)
+
+	saved, err := os.ReadFile(filepath.Join(root, "view.json"))
+	require.NoError(t, err)
+
+	_, err = memory.Append("user", "second")
+	require.NoError(t, err)
+
+	view := memory.View()
+	require.NoError(t, memory.Close())
+
+	// The log and the tree hold message 1, but the view does not.
+	require.NoError(t, os.WriteFile(filepath.Join(root, "view.json"), saved, 0o600))
+
+	memory, err = openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
+	require.NoError(t, err)
+	require.Equal(t, view, memory.View())
+	require.NoError(t, memory.Close())
+}
+
+func TestMemoryKeepsTheCompactionViewCoarser(t *testing.T) {
+	memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now, newFakeSummarizer())
+	require.NoError(t, err)
+
+	defer func() {
+		require.NoError(t, memory.Close())
+	}()
+
+	memory.chat.high = 200
+	memory.chat.low = 100
+	memory.cview.high = 80
+	memory.cview.low = 40
+	for n := range 64 {
+		_, err = memory.Append("user", fmt.Sprint(n%10))
+		require.NoError(t, err)
+
+		coarse := 0
+		for _, line := range memory.chat.lines {
+			outer := memory.cview.lines[coarse]
+			for nodeEnd(outer.level, outer.index) <= line.index<<line.level {
+				coarse++
+				outer = memory.cview.lines[coarse]
+			}
+
+			require.GreaterOrEqual(t, outer.level, line.level, "message %d", n)
+		}
+	}
+}
+
+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() == maxBuilds
+	}, 10*time.Second, time.Millisecond)
+
+	close(summarizer.gate)
+	require.NoError(t, memory.Wait(t.Context()))
+	require.Equal(t, maxBuilds, 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))
+}
+
 func TestMemoryBuildsFreeParents(t *testing.T) {
-	memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now)
+	memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	defer func() {
@@ -55,29 +244,40 @@ func TestMemoryBuildsFreeParents(t *testing.T) {
 		require.NoError(t, err)
 	}
 
-	node, built := memory.tree.Node(2, 0)
-	require.True(t, built)
+	node := readNode(t, memory.tree, 2, 0)
 	require.Equal(t, "user: a\nuser: b\nuser: c\nuser: d", node.Text)
 }
 
 func TestMemoryKeepsALongMessageOutOfTheView(t *testing.T) {
-	memory, err := openMemory(t.Context(), t.TempDir(), newTestClock().Now)
+	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())
 	}()
 
-	_, err = memory.Append("echo", string(make([]byte, nodeBytes)))
+	_, err = memory.Append("echo", longText(0))
 	require.NoError(t, err)
-
+	require.NoError(t, memory.Wait(t.Context()))
 	require.Equal(t, "<chat>\n0+1|"+pending+"\n</chat>", memory.View())
+
+	summarizer.SetFailing(false)
+
+	_, err = memory.Append("user", "again")
+	require.NoError(t, err)
+	require.NoError(t, memory.Wait(t.Context()))
+
+	task, err := memory.task(nodeKey{0, 0})
+	require.NoError(t, err)
+	require.Equal(t, "<chat>\n0+1|"+fakeLine(task)+"\n1+1|user: again\n</chat>", memory.View())
 }
 
 func TestMemoryCoversMessagesAfterTheSavedView(t *testing.T) {
 	root := t.TempDir()
 	clock := newTestClock()
-	memory, err := openMemory(t.Context(), root, clock.Now)
+	memory, err := openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	_, err = memory.Append("user", "a")
@@ -87,7 +287,7 @@ func TestMemoryCoversMessagesAfterTheSavedView(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, memory.Close())
 
-	memory, err = openMemory(t.Context(), root, clock.Now)
+	memory, err = openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	defer func() {
@@ -100,7 +300,7 @@ func TestMemoryCoversMessagesAfterTheSavedView(t *testing.T) {
 func TestMemoryRefusesToRebuildAMissingView(t *testing.T) {
 	root := t.TempDir()
 	clock := newTestClock()
-	memory, err := openMemory(t.Context(), root, clock.Now)
+	memory, err := openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.NoError(t, err)
 
 	_, err = memory.Append("user", "a")
@@ -108,6 +308,94 @@ func TestMemoryRefusesToRebuildAMissingView(t *testing.T) {
 	require.NoError(t, memory.Close())
 	require.NoError(t, os.Remove(filepath.Join(root, "view.json")))
 
-	_, err = openMemory(t.Context(), root, clock.Now)
+	_, err = openMemory(t.Context(), root, clock.Now, newFakeSummarizer())
 	require.ErrorIs(t, err, errNoView)
 }
+
+// fakeSummarizer builds each node with a line of fakeLine. It fails each task
+// while failing is true, and each task waits for gate when gate is not nil.
+type fakeSummarizer struct {
+	mutex   sync.Mutex
+	gate    chan struct{}
+	failing bool
+	active  int
+	peak    int
+	tasks   []Task
+}
+
+func newFakeSummarizer() *fakeSummarizer {
+	return &fakeSummarizer{}
+}
+
+func (f *fakeSummarizer) Summarize(ctx context.Context, task Task) (string, error) {
+	f.mutex.Lock()
+	f.tasks = append(f.tasks, task)
+	f.active++
+	f.peak = max(f.peak, f.active)
+	fail := f.failing
+	f.mutex.Unlock()
+
+	defer func() {
+		f.mutex.Lock()
+		f.active--
+		f.mutex.Unlock()
+	}()
+
+	if f.gate != nil {
+		select {
+		case <-f.gate:
+		case <-ctx.Done():
+			return "", ctx.Err()
+		}
+	}
+
+	if fail {
+		return "", errors.New("fake failure")
+	}
+
+	return fakeLine(task), nil
+}
+
+// fakeLine returns a line of nodeBytes bytes or less that names the node and
+// starts with the input. A real line of this size makes each merge a model
+// call.
+func fakeLine(task Task) string {
+	count := 1 << task.Level
+	line := fmt.Sprintf("summary %d+%d: %s", task.Index*count, count, strings.Join(task.Input, " "))
+	line = strings.ReplaceAll(line, "\n", " ")
+	for len(line) > nodeBytes-12 {
+		_, size := utf8.DecodeLastRuneInString(line)
+		line = line[:len(line)-size]
+	}
+
+	return line
+}
+
+// longText returns a text that is too long for its own node.
+func longText(n int) string {
+	return fmt.Sprintf("long %d ", n) + strings.Repeat("x", nodeBytes)
+}
+
+// SetFailing makes the next tasks fail or not.
+func (f *fakeSummarizer) SetFailing(failing bool) {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	f.failing = failing
+}
+
+// Active returns the number of tasks that run now.
+func (f *fakeSummarizer) Active() int {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	return f.active
+}
+
+// Tasks returns the tasks so far.
+func (f *fakeSummarizer) Tasks() []Task {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	return slices.Clone(f.tasks)
+}