fix(ol_dbt_cli): sql_parser — don't collapse a macro-as-function-argument into a CTE

[blarghmatey]

Summary

• 4th defect in the "Jinja-collapse" family (see fix(ol_dbt_cli): sql_parser — fix 3 Jinja-collapse defects (trailing-comma CTE, alias loss, subquery FP) #2454): the trailing-comma-CTE rule matched any __macro__,/__undefined__, line and rewrote it as a synthetic CTE, but that same shape also occurs when a macro call is the first argument of a multi-line function call (e.g. coalesce({{ macro(...) }}, ...)), corrupting the argument list and silently degrading the parse to zero output columns — a false-positive "columns missing from SQL" ERROR.
• Fix distinguishes the two shapes by the character preceding the placeholder line: ) (end of previous CTE) → genuine CTE position; ( or , (inside a call) → leave the placeholder alone.
• Found via tfact_chatbot_events.sql unexpectedly failing ol-dbt validate on two unrelated open PRs (feat(dbt): add 18 missing starrocks__ cross-db macro variants #2417, fix(dimensional): fix dim_discount grain mismatch causing tfact_order fan-out #2411) once it entered "changed models" scope — the model's own SQL/YAML were untouched; the bug was latent on main all along.

Test plan

• cd src/ol_dbt_cli && uv run pytest — 356 passed, no regressions
• New regression test test_macro_as_first_function_argument_not_treated_as_cte — confirmed it fails without the fix and passes with it
• ol-dbt validate --model tfact_chatbot_events clean on fresh checkouts of both affected PR branches
• Full-project ol-dbt validate (no filter) — 0 ERRORs on both affected branches
• pre-commit (ruff/mypy/sqlfluff) clean

🤖 Generated with Claude Code

[github-actions]

🔎 ol-dbt impact — column-level blast radius

✅ No column-level downstream impact detected for the changed models.

_{Posted by ol-dbt impact (annotate-only — does not block merge).}

[Copilot]

Pull request overview

This PR fixes a false-positive rewrite in ol_dbt_cli’s Jinja rendering post-processing: a line that looks like a “trailing-comma macro placeholder CTE” is now only rewritten into a synthetic CTE when it is actually in a top-level CTE-list position, avoiding corruption of multi-line function argument lists (and the downstream “zero output columns” parsing degradation).

Changes:

• Refine the “__macro__, / __undefined__, on its own line” rewrite to only fire when the preceding non-whitespace character indicates a CTE boundary (currently: )).
• Add a regression test ensuring a macro used as the first argument of a multi-line function call is not treated as a CTE placeholder.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/ol_dbt_cli/ol_dbt_cli/lib/sql_parser.py	Tightens the trailing-comma macro rewrite by inspecting preceding context before rewriting to a synthetic CTE.
src/ol_dbt_cli/tests/test_sql_parser.py	Adds a regression test covering the macro-as-function-argument shape to prevent reintroducing the false-positive rewrite.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.