brain: remove ForgetDuring and ForgetUserSince methods

We keep the information needed to implement these in terms of only
message IDs elsewhere.

Fixes #52.
For #90.

Author: zephyrtronium

brain/braintest/braintest.go

@@ -18,8 +18,7 @@ import (
 // If a brain cannot be created without error, new should call t.Fatal.
 func Test(ctx context.Context, t *testing.T, new func(context.Context) brain.Brain) {
 	t.Run("speak", testSpeak(ctx, new(ctx)))
-	t.Run("forgetMessage", testForgetMessage(ctx, new(ctx)))
-	t.Run("forgetDuring", testForgetDuring(ctx, new(ctx)))
+	t.Run("forgetMessage", testForget(ctx, new(ctx)))
 	t.Run("combinatoric", testCombinatoric(ctx, new(ctx)))
 }
 
@@ -182,11 +181,11 @@ func testSpeak(ctx context.Context, br brain.Brain) func(t *testing.T) {
 	}
 }
 
-// testForgetMessage tests that a brain can forget messages by ID.
-func testForgetMessage(ctx context.Context, br brain.Brain) func(t *testing.T) {
+// testForget tests that a brain can forget messages by ID.
+func testForget(ctx context.Context, br brain.Brain) func(t *testing.T) {
 	return func(t *testing.T) {
 		learn(ctx, t, br)
-		if err := br.ForgetMessage(ctx, "kessoku", messages[0].ID); err != nil {
+		if err := br.Forget(ctx, "kessoku", messages[0].ID); err != nil {
 			t.Errorf("failed to forget first message: %v", err)
 		}
 		got := speak(ctx, t, br, "kessoku", "", 2048)
@@ -233,51 +232,6 @@ func testForgetMessage(ctx context.Context, br brain.Brain) func(t *testing.T) {
 	}
 }
 
-// testForgetDuring tests that a brain can forget messages in a time range.
-func testForgetDuring(ctx context.Context, br brain.Brain) func(t *testing.T) {
-	return func(t *testing.T) {
-		learn(ctx, t, br)
-		if err := br.ForgetDuring(ctx, "kessoku", time.Unix(1, 0).Add(-time.Millisecond), time.Unix(2, 0).Add(time.Millisecond)); err != nil {
-			t.Errorf("failed to forget: %v", err)
-		}
-		got := speak(ctx, t, br, "kessoku", "", 2048)
-		want := map[string]struct{}{
-			"1#member bocchi":   {},
-			"1 4#member bocchi": {},
-			"1 4#member kita":   {},
-			"4#member kita":     {},
-		}
-		if diff := cmp.Diff(want, got); diff != "" {
-			t.Errorf("wrong messages after forgetting (+got/-want):\n%s", diff)
-		}
-		got = speak(ctx, t, br, "sickhack", "", 2048)
-		want = map[string]struct{}{
-			"5#member bocchi":   {},
-			"5 6#member bocchi": {},
-			"5 7#member bocchi": {},
-			"5 8#member bocchi": {},
-			"5 6#member ryou":   {},
-			"6#member ryou":     {},
-			"6 7#member ryou":   {},
-			"6 8#member ryou":   {},
-			"5 7#member nijika": {},
-			"6 7#member nijika": {},
-			"7#member nijika":   {},
-			"7 8#member nijika": {},
-			"5 8#member kita":   {},
-			"6 8#member kita":   {},
-			"7 8#member kita":   {},
-			"8#member kita":     {},
-			"9#manager seika":   {},
-		}
-		if diff := cmp.Diff(want, got); diff != "" {
-			t.Errorf("wrong spoken messages for sickhack (+got/-want):\n%s", diff)
-		}
-	}
-}
-
-// TODO(zeph): testForgetUser
-
 // testCombinatoric tests that chains can generate even with substantial
 // overlap in learned material.
 func testCombinatoric(ctx context.Context, br brain.Brain) func(t *testing.T) {

brain/braintest/braintest_test.go

@@ -66,55 +66,13 @@ func (m *membrain) forgetIDLocked(tag, id string) {
 	}
 }
 
-func (m *membrain) Forget(ctx context.Context, tag string, tuples []brain.Tuple) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	for _, tup := range tuples {
-		p := strings.Join(tup.Prefix, "\xff")
-		u := m.tups[tag][p]
-		k := slices.IndexFunc(u, func(v [2]string) bool { return v[1] == tup.Suffix })
-		if k < 0 {
-			continue
-		}
-		u[k], u[len(u)-1] = u[len(u)-1], u[k]
-		m.tups[tag][p] = u[:len(u)-1]
-	}
-	return nil
-}
-
-func (m *membrain) ForgetMessage(ctx context.Context, tag, id string) error {
+func (m *membrain) Forget(ctx context.Context, tag, id string) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	m.forgetIDLocked(tag, id)
 	return nil
 }
 
-func (m *membrain) ForgetDuring(ctx context.Context, tag string, since, before time.Time) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	s, b := since.UnixNano(), before.UnixNano()
-	for tm, u := range m.tms[tag] {
-		if tm < s || tm > b {
-			continue
-		}
-		for _, v := range u {
-			m.forgetIDLocked(tag, v)
-		}
-		delete(m.tms[tag], tm) // yea i modify the map during iteration, yea i'm cool
-	}
-	return nil
-}
-
-func (m *membrain) ForgetUser(ctx context.Context, user *userhash.Hash) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-	for _, v := range m.users[*user] {
-		m.forgetIDLocked(v[0], v[1])
-	}
-	delete(m.users, *user)
-	return nil
-}
-
 func (m *membrain) Speak(ctx context.Context, tag string, prompt []string, w *brain.Builder) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()

brain/kvbrain/forget.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"slices"
 	"sync"
-	"time"
 
 	"github.com/zephyrtronium/robot/userhash"
 )
@@ -53,45 +52,9 @@ func (p *past) findID(id string) [][]byte {
 	return nil
 }
 
-// findDuring finds all knowledge keys of messages recorded with timestamps in
-// the given time span.
-func (p *past) findDuring(since, before int64) [][]byte {
-	r := make([][]byte, 0, 64)
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	for k, v := range p.time {
-		if since <= v && v <= before {
-			keys := p.key[k]
-			r = slices.Grow(r, len(keys))
-			for _, v := range keys {
-				r = append(r, bytes.Clone(v))
-			}
-		}
-	}
-	return r
-}
-
-// findUser finds all knowledge keys of messages recorded from a given user
-// since a timestamp.
-func (p *past) findUser(user userhash.Hash) [][]byte {
-	r := make([][]byte, 0, 64)
-	p.mu.Lock()
-	defer p.mu.Unlock()
-	for k, v := range p.user {
-		if v == user {
-			keys := p.key[k]
-			r = slices.Grow(r, len(keys))
-			for _, v := range keys {
-				r = append(r, bytes.Clone(v))
-			}
-		}
-	}
-	return r
-}
-
-// ForgetMessage forgets everything learned from a single given message.
+// Forget forgets everything learned from a single given message.
 // If nothing has been learned from the message, it should be ignored.
-func (br *Brain) ForgetMessage(ctx context.Context, tag, id string) error {
+func (br *Brain) Forget(ctx context.Context, tag, id string) error {
 	past, _ := br.past.Load(tag)
 	if past == nil {
 		return nil
@@ -111,53 +74,3 @@ func (br *Brain) ForgetMessage(ctx context.Context, tag, id string) error {
 	}
 	return nil
 }
-
-// ForgetDuring forgets all messages learned in the given time span.
-func (br *Brain) ForgetDuring(ctx context.Context, tag string, since, before time.Time) error {
-	past, _ := br.past.Load(tag)
-	if past == nil {
-		return nil
-	}
-	keys := past.findDuring(since.UnixNano(), before.UnixNano())
-	batch := br.knowledge.NewWriteBatch()
-	defer batch.Cancel()
-	for _, key := range keys {
-		err := batch.Delete(key)
-		if err != nil {
-			return err
-		}
-	}
-	err := batch.Flush()
-	if err != nil {
-		return fmt.Errorf("couldn't commit deleting between times %v and %v: %w", since, before, err)
-	}
-	return nil
-}
-
-// ForgetUser forgets all messages associated with a userhash.
-func (br *Brain) ForgetUser(ctx context.Context, user *userhash.Hash) error {
-	var rangeErr error
-	u := *user
-	br.past.Range(func(tag string, past *past) bool {
-		keys := past.findUser(u)
-		if len(keys) == 0 {
-			return true
-		}
-		batch := br.knowledge.NewWriteBatch()
-		defer batch.Cancel()
-		for _, key := range keys {
-			err := batch.Delete(key)
-			if err != nil {
-				rangeErr = err
-				return false
-			}
-		}
-		err := batch.Flush()
-		if err != nil {
-			rangeErr = fmt.Errorf("couldn't commit deleting messages by user: %w", err)
-			return false
-		}
-		return false
-	})
-	return rangeErr
-}