The scenario suite shipped with one smoke test (CREATE TABLE +
idempotent re-apply). Add four more scenarios so the CLI covers the
features users actually exercise day-to-day, plus extend the
existing helpers with a couple of generic assertion primitives.

Scenarios

  - evolution.test.sh — walks one schema through six stages:
    CREATE → ADD COLUMN → ADD INDEX → ADD CONSTRAINT FK →
    MODIFY COLUMN (widen) → DROP COLUMN (with column-attached index
    auto-suppression). Each step asserts no drift after apply, so a
    regression in any of those ALTER paths surfaces here.

  - rename.test.sh — exercises `-- myschema:renamed-from` end-to-end
    via the CLI: table rename → column rename → index rename
    (KEY + UNIQUE in one step). Each step pins the right
    ALTER … RENAME form lands in plan output and post-apply plan
    is silent.

  - dump_roundtrip.test.sh — load a non-trivial schema (tables,
    FK ON DELETE CASCADE, view), `myschema dump` it to a temp file,
    drop the DB, re-apply the dump, then plan against the *original*
    source SQL — expects no drift. Pins that the dump renderer
    produces SQL the parser can read back.

  - views.test.sh — view lifecycle: ADD → MODIFY body
    (CREATE OR REPLACE) → DROP under --allow-drop=all.

  - filter.test.sh — `--include` / `--exclude` with three tables in
    the DB but only one in desired. Asserts filtered tables don't
    show as drops; unfiltered ones do; glob patterns match.

Helpers

  helper.sh gains two generic assertion primitives so scenarios
  beyond the existing run_step* shape can assert on raw command
  output without each rolling its own grep/diff:

  - assert_contains <step> <cmd...> -- <substring>
  - assert_not_contains <step> <cmd...> -- <substring>

  Plus a `myschema_dump` thin wrapper to match the existing
  myschema_plan / myschema_apply pair.

Verified locally on both compose services (8.0 / 9.4): all 22
scenario steps pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Five inline comments, all valid.

helper.sh
  - assert_contains / assert_not_contains now capture stderr too
    (`2>&1`) so a command that prints the relevant text to stderr
    doesn't cause a false negative. (Copilot #1, #2.)
  - Both helpers explicitly validate the invocation: missing `--`
    separator, no command before `--`, or no substring after `--`
    each fail with a clear message instead of letting bash run a
    malformed command and produce an opaque "command not found"
    or hang on stdin. (Copilot #1, #2.)
  - Sanity-checked all four validation paths (`missing sep`,
    `missing cmd`, `missing substring`, `stderr capture`) by
    sourcing helper.sh in a one-shot bash session.

dump_roundtrip.test.sh
  - The dump-failure and apply-failure branches now `summary; exit 1`
    after `fail`, instead of falling through to the next step. The
    cascading errors that followed obscured the original failure;
    failing fast keeps the scenario log focused on the root cause.
    (Copilot #3, #4.)

evolution.test.sh
  - Header comment said "ADD COLUMN with DEFAULT" but the fixture
    drops the DEFAULT (workaround for the catalog default-
    normalisation drift documented in TODO.md). Comment now matches
    reality and points at the TODO entry. (Copilot #5.)

`make test-scenario` (mysql 8.0) — all 22 steps still pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Three inline comments, all valid.

helper.sh
  - myschema_dump no longer merges stderr into stdout. Callers
    typically redirect stdout to a .sql file (dump_roundtrip
    re-applies the dump), and any stderr text would otherwise be
    embedded in the dump and break re-apply. Plan / apply wrappers
    keep `2>&1` because their callers run them through `out=$(...)`
    and want both streams. (Copilot #1.)

evolution.test.sh
  - Step "06 DROP COLUMN + auto-index" only asserted the plan
    contains DROP COLUMN; if the column-attached index suppression
    regressed and DROP INDEX users_display_name_idx leaked through,
    apply would still succeed (because MySQL has already auto-removed
    the index, but `Error 1091` would surface — actually a real
    failure). Add an explicit assert_not_contains BEFORE run_step
    so the suppression behaviour itself is pinned in plan output,
    independent of apply outcome. (Copilot #2.)

filter.test.sh
  - Step 01's comment claimed `--include=users` hides BOTH sessions
    and logs, but the assertion only checked sessions. Split into
    two explicit assert_not_contains so both filter targets are
    covered. (Copilot #3.)

`make test-scenario` (mysql 8.0) — all 24 steps pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Copilot review #3 follow-up nit: the helpers only consumed `$1`
after the `--` separator and silently ignored anything after it. So
an unquoted multi-word substring (`-- DROP TABLE foo`) would only
search for "DROP" — passing/failing on the wrong target without any
warning.

Add a `$# -ne 1` check after parsing the separator so a missing
quote fails loudly with a clear message that points at the fix
("too many arguments after '--' (got N); quote the substring").
Sanity-checked by sourcing helper.sh in a one-shot bash session
and confirming the error fires.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Five Copilot inline comments on PR #31, all valid:

helper.sh
  - assert_contains / assert_not_contains validate $# >= 1 before
    referencing $1 / shifting. Under `set -u` (which the scenario
    runner enables), a no-arg call would otherwise abort with
    "unbound variable" instead of falling into the helper's own
    fail() path. (Copilot #1, #2.)
  - Replace `echo "$out" | grep ...` with
    `printf '%s\n' "$out" | grep -qF -- ...`. echo can mangle
    output that starts with `-n` / contains escape sequences;
    printf is faithful, and the `--` after `-qF` keeps grep from
    treating a leading `-` in the substring as an option.
    (Copilot #3, #4.)

test/scenario/dump_roundtrip.test.sh
  - `mktemp -d` without a template is GNU-specific; macOS / BSD
    requires one. Pass an explicit template under `$TMPDIR` so the
    scenario runs portably. (Copilot #5.)

`make test-scenario` (mysql 8.0) — all 24 steps still pass.
Sanity-checked the `set -u` path by sourcing helper.sh in a fresh
bash session and calling `assert_contains` with no args; it now
returns via fail() instead of aborting.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Two Copilot inline comments on PR #31:

helper.sh
  - Extract the shared parsing / validation / command-execution
    logic of assert_contains and assert_not_contains into a single
    `_assert_substring <mode>` private helper. The two public
    wrappers shrink to one-liners that only choose the mode, so
    diagnostics and behaviour stay in lockstep going forward.
    (Copilot #2.)

filter.test.sh
  - Step 01 only asserted DROP TABLE for the excluded targets was
    *absent*. An unrelated ALTER on `users` could still slip
    through. Add an explicit "No changes" assertion for the
    `-I users` case so the test pins clean-diff behaviour, not just
    absence-of-drops. (Copilot #1.)

`make test-scenario` (mysql 8.0) — all 25 steps pass (gain one).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Three Copilot inline comments on PR #31:

helper.sh
  - `_assert_substring` now rejects an empty needle. `grep -qF -- ""`
    always matches, so `assert_contains ... -- ''` would silently
    pass (and `_not_contains` would always fail) regardless of
    output. Almost always a caller bug — fail loudly with
    "substring is empty". (Copilot #1.)

testdata/rename/04_rename_index.sql
  - Header comment claimed the UNIQUE index was "previously-
    renamed", but step 03 only renames a column; both indexes are
    actually renamed in step 04. Reword to spell out both
    renames explicitly. (Copilot #2.)

filter.test.sh
  - Step labels jumped 02 → 03 mid-block. Renumber so the two
    `--exclude=log*` checks are 02a/02b and the two no-filter
    checks are 03a/03b, matching the comment grouping. (Copilot #3.)

`make test-scenario` (mysql 8.0) — all 25 steps still pass.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>