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

src/ol_dbt_cli/ol_dbt_cli/lib/sql_parser.py

@@ -158,9 +158,27 @@ def _render_jinja(sql: str) -> tuple[str, list[str], list[str], dict[str, str],
     # The leading comma reconnects to the preceding CTE: these injector macros
     # (e.g. deduplicate_raw_table) emit leading-comma CTEs and always follow a
     # `source`/base CTE, which itself carries no trailing comma.
+    #
+    # The same "placeholder alone on its line, trailing comma" shape also occurs when
+    # a macro call is simply the *first argument* of a multi-line function call, e.g.
+    # ``coalesce(\n    {{ macro(...) }},\n    regexp_extract(...)\n)``. There the
+    # placeholder is not a CTE at all — it is nested inside the call's parens — and
+    # rewriting it as a CTE definition corrupts the argument list. sqlglot's
+    # error_level=IGNORE then degrades gracefully to a stray ``select 1``, so the
+    # model appears to parse cleanly but yields zero output columns (a false-positive
+    # "columns missing from SQL" error). Distinguish the two shapes by inspecting the
+    # nearest preceding non-whitespace character: a genuine CTE-position macro always
+    # immediately follows the closing ``)`` of the previous CTE's body, whereas a macro
+    # used as a function argument follows an opening ``(`` or a sibling-argument ``,``.
+    def _replace_trailing_comma_macro(m: re.Match[str]) -> str:
+        prefix = rendered[: m.start()].rstrip()
+        if prefix.endswith(")"):
+            return ", __jinja_cte__ as (select 1),"
+        return m.group(0)  # function-argument position — leave the bare placeholder as-is
+
     rendered = re.sub(
         r"(?m)^[^\S\r\n]*(?:__macro__|__undefined__)[^\S\r\n]*,[^\S\r\n]*$",
-        ", __jinja_cte__ as (select 1),",
+        _replace_trailing_comma_macro,
         rendered,
     )
     # Block-level macro injections (macros that inject CTE SQL fragments) render as

src/ol_dbt_cli/tests/test_sql_parser.py

@@ -353,6 +353,36 @@ def test_multiline_function_over_macro_keeps_alias(self) -> None:
         assert result.parse_error is None
         assert "program_readable_id" in result.output_columns
 
+    def test_macro_as_first_function_argument_not_treated_as_cte(self) -> None:
+        r"""A macro call as a function argument must not be treated as a CTE placeholder.
+
+        `coalesce(\n    {{ macro(...) }},\n    regexp_extract(...)\n)` renders the
+        macro call to `__macro__,` alone on its line — the exact same shape the
+        trailing-comma-CTE rule (for `{{ deduplicate_raw_table(...) }},` between two
+        named CTEs) matches on. But here the placeholder is nested inside `coalesce(`'s
+        parens, not sitting between two top-level CTEs. Rewriting it as
+        `, __jinja_cte__ as (select 1),` corrupts the argument list; sqlglot's
+        error_level=IGNORE then silently degrades to a stray `select 1`, so the model
+        "parses" but yields zero output columns — a false-positive "columns missing
+        from SQL" error (tfact_chatbot_events regression). The two shapes are told
+        apart by the character preceding the placeholder line: a genuine CTE-position
+        macro always follows the closing `)` of the previous CTE, while a
+        function-argument macro follows the call's opening `(`.
+        """
+        sql = (
+            "with report as (select 1 as event_id, 'x' as event_value)\n"
+            "select\n"
+            "    report.event_id\n"
+            "    , coalesce(\n"
+            "        {{ json_query_string('event_value', \"'$.thread_id'\") }},\n"
+            "        regexp_extract(report.event_value, 'x', 1)\n"
+            "    ) as thread_id\n"
+            "from report"
+        )
+        result = parse_model_sql("my_model", sql)
+        assert result.parse_error is None
+        assert result.output_columns == {"event_id", "thread_id"}
+
     def test_var_in_where_clause_parseable(self) -> None:
         """A model with '{{ var(...) }}' in WHERE must parse without error."""
         sql = (