cmd/loop: drop legacy text payload shim

Remove the temporary reader fallback that accepted the old
text-based stdout and stderr payloads now that the recorded
session corpus has been rewritten. The remaining code only
handles the line-based layout and keeps the replay and
recorder path focused on the final schema.

Drop the transition-only test coverage alongside the shim.
The steady-state tests continue to cover replay, blessing,
and timestamp normalization against the converted fixtures.

Author: starius

cmd/loop/session_fixture_update_test.go

@@ -571,32 +571,6 @@ func TestRewriteSessionFixtureSkipsNormalizedTimestampNoise(t *testing.T) {
 	require.Equal(t, fixture, updated)
 }
 
-// TestRewriteSessionFixtureCanonicalizesLegacyText verifies that bless mode
-// rewrites legacy text payloads into the canonical line-based layout even when
-// the visible output is unchanged.
-func TestRewriteSessionFixtureCanonicalizesLegacyText(t *testing.T) {
-	fixture := sessionFile{
-		Events: []sessionEvent{
-			legacyTextEvent(t, 2, eventStdout, "hello\nworld\n"),
-			exitEvent(t, 3, nil),
-		},
-	}
-
-	updated, changed, err := rewriteSessionFixture(fixture,
-		replayedSessionOutput{
-			stdout:       "hello\nworld\n",
-			stdoutChunks: []string{"hello\nworld\n"},
-		},
-	)
-	require.NoError(t, err)
-	require.True(t, changed)
-	require.Equal(t, "hello\nworld\n", textEventText(t, updated.Events[0]))
-
-	var payload textPayload
-	require.NoError(t, json.Unmarshal(updated.Events[0].Data, &payload))
-	require.Equal(t, []string{"hello\n", "world\n"}, payload.Lines)
-}
-
 // textEvent builds a text session event for tests.
 func textEvent(t *testing.T, timeMS int64, kind, text string) sessionEvent {
 	t.Helper()
@@ -611,24 +585,6 @@ func textEvent(t *testing.T, timeMS int64, kind, text string) sessionEvent {
 	}
 }
 
-// legacyTextEvent builds a legacy text payload for transition tests.
-func legacyTextEvent(t *testing.T, timeMS int64, kind, text string) sessionEvent {
-	t.Helper()
-
-	data, err := json.Marshal(struct {
-		Text string `json:"text"`
-	}{
-		Text: text,
-	})
-	require.NoError(t, err)
-
-	return sessionEvent{
-		TimeMS: timeMS,
-		Kind:   kind,
-		Data:   data,
-	}
-}
-
 // exitEvent builds an exit session event for tests.
 func exitEvent(t *testing.T, timeMS int64, runError *string) sessionEvent {
 	t.Helper()

cmd/loop/session_recorder.go

@@ -107,33 +107,6 @@ func (p textPayload) text() string {
 	return joinTextLines(p.Lines)
 }
 
-// UnmarshalJSON accepts the current line-based layout and the previous
-// text-based layout so fixtures can be transitioned in place.
-func (p *textPayload) UnmarshalJSON(data []byte) error {
-	var payload struct {
-		Lines []string `json:"lines"`
-		Text  *string  `json:"text"`
-	}
-	if err := json.Unmarshal(data, &payload); err != nil {
-		return err
-	}
-
-	switch {
-	case payload.Lines != nil:
-		p.Lines = append([]string(nil), payload.Lines...)
-
-		return nil
-
-	case payload.Text != nil:
-		p.Lines = splitTextLines(*payload.Text)
-
-		return nil
-
-	default:
-		return errors.New("missing text payload lines")
-	}
-}
-
 // stdinPayload records stdin chunks.
 type stdinPayload struct {
 	Text string `json:"text"`