Trust the statement count, not the stopwatch: this machine's suite timings
drift about 20% between runs, so the branch-read regression is recorded as
201 SELECTs -> 2 rather than as seconds.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Dvvqn9ZDR4ixeFPHNbww7
The identity map holds weak references. A branch row nobody keeps a strong
reference to is collected between two nodes, so resolving the head inside the
placement loop read it back from the database for every node in the flush: 201
SELECTs on `branches` to write 200 actions, and 36 s -> 45 s on the same 297
tests. Nothing about any result changed, which is why only a stopwatch found
it, and why there is now a test counting the reads.
Also: the two reads left un-pathed on purpose say so where they live —
`max_action_index` allocates the legacy `index` and must stay adventure-wide
or two branches issue the same number, and export is a flat v1 bundle whose
reader has no idea branches exist. And `Adventure.actions` keeps its `index`
ordering, because ordering the collection by depth would not make it a story:
it is every branch's actions, and a path is a selection out of it.
318 tests green.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Dvvqn9ZDR4ixeFPHNbww7
Phase 14 SP1. The tree goes into the schema and nothing reads it yet: a
`branches` table, `branch_id`/`depth` on actions and memories, a head pointer
on adventures, migrations 46-52, and a server-side backfill that re-reads every
existing adventure as a tree with one branch. `depth` holds the number `index`
already held, gaps included, so no story changes — a linear story *is* a tree
with one branch, which is what makes the SP0 baseline passing unmodified the
pass condition rather than a hope.
The writer had to come with it. No migration will ever visit a row written
after it ran, so columns backfilled today and populated next subphase would
leave a hole exactly the width of one deploy, and from SP2 on a row without a
branch is a row no read can see. `app/tree.py` owns that: one module, because a
node written without a branch fails by disappearing rather than by raising.
Three things the schema itself insisted on:
- `adventures.head_branch_id` is a plain integer, not a foreign key. Pointing
both ways makes the two tables a cycle create_all cannot order, and its
escape hatch needs an ALTER SQLite does not have. It is a cache, and a head
naming a branch that is gone recovers onto the root.
- `lineage` is NOT NULL, so the backfill inserts `'[]'` and fills it in a
second pass guarded on `json_array_length(lineage) = 0` — not `= '[]'`,
because Postgres `json` has no equality operator.
- SQLite will not drop a column a foreign key names, which is how two existing
tests broke: they simulated an old database by rewinding the stamp while
leaving the new columns in place. Every ADD COLUMN migration is now
idempotent, and `tests/test_tree_migration.py` builds a genuine schema 45 by
rebuilding three tables from frozen DDL so the real ALTERs run.
297 tests green, 14 of them new. `branches` costs 0.1 kB of a 733.5 kB turn;
page load and index are byte-identical to the recorded figures.
The deploy that ships this needs one `VACUUM FULL actions;` on the direct
endpoint afterwards — it rewrites every row.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Dvvqn9ZDR4ixeFPHNbww7
The stress fixture is sized from production and exists to weigh bytes, so it
leaves every column it does not weigh at its default. Checked against a freshly
built one, that is exactly the set phase 14 has to migrate: state_before and
world_state_before NULL on all 600 rows, no scenario and so no RPG layer, no
adventure scripts, both cursors 0, and a hundred retry histories whose two
attempts carry byte-identical text with variant_index pinned at 0.
That last one matters most. "Which attempt is live?" is the question SP4's
migration answers when it decides which sibling node becomes the head of a
turn, and against that fixture the question had no observable answer -- a
migration that picked wrong would have looked correct.
--rich fills in those columns and no others. A real RPG scenario read from the
seed data rather than invented, with a world state played forward so hp
declines and flags flip; monotonic per-action state snapshots, so a rollback
that does not happen reads as a wrong number instead of as nothing; a gold
script, story cards, non-zero cursors, pinned and forgotten memories; retry
attempts with distinct texts, counts of two and three, and a live attempt that
is often not the last written. Plus a second adventure, because a branch clause
that forgot its adventure still looks right on a database holding one.
The invariant SP4 reads -- text mirrors variants[variant_index] -- is asserted
at build time rather than assumed.
The plain fixture is untouched and re-measured unchanged at 1.8 kB, so the
egress ceilings stay comparable. All six shapes run clean on --rich, including
the turn path with the RPG layer and script pipeline now live. 283 tests pass.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Dvvqn9ZDR4ixeFPHNbww7
Phase 14 replaces the action list with a tree, which touches the memory bank,
the context builder, undo, retry and the UI at once. Before any of that moves,
write down what "unaffected" means and prove it holds today.
tests/test_story_tree_baseline.py drives the product over HTTP the way a player
does and asserts only on API responses, never on how anything is stored: the
turn engine, retry and variant switching, undo, paging all the way back to the
start without gaps or repeats, edit/delete, memories, export/import round-trip,
world state. 283 green with it added, from 259.
It must pass unmodified through the schema change, the branch clause and the
move of memories onto nodes. A linear story is a tree with one branch, so those
subphases have no licence to change behaviour, and this is what says so.
The plan itself records four decisions that were open: structural-first with no
runtime flag, legacy columns kept one release, full tree visualisation, and a
v2 bundle with a v1 reader. Plus four traps found by reading rather than
running -- history._from_memory and the scripting pipeline both slice
adventure.actions, which under a tree is every branch rather than the path.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017Dvvqn9ZDR4ixeFPHNbww7
Two plan documents from designing the branching story tree. The tree work
turned up that memory retrieval fetches the whole bank's embeddings every
turn -- 96% of a turn's database traffic -- and that is the one read a tree
cannot window, so it lands first.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015CYEJKobJ2Re4Dv7qUoSA7
