Migration runner splits SQL on ';' inside '--' line comments

[justin-k-bruce]

Summary: _split_statements() splits SQL on ; before stripping -- line comments, so a semicolon inside a -- comment breaks the statement mid-way. Severity: high (migrations fail unpredictably; the trigger is invisible — a ; in a comment).

Version: tina4-python 3.13.37.

Where

tina4_python/migration/runner.py::_split_statements() (~lines 301–347). It saves $$…$$///…// blocks as placeholders and strips /* */, then:

clean = re.sub(r"/\*.*?\*/", "", processed, flags=re.DOTALL)
...
for stmt in clean.split(delimiter):          # <-- splits on ';' FIRST (~line 328)
    for line in stmt.split("\n"):            # <-- only NOW removes '--' comments, too late
        stripped = line.strip()
        if stripped and not stripped.startswith("--"):
            ...

By the time -- comments are handled per-line, the ; inside a comment has already split the statement into broken fragments.

Repro / regression test

from tina4_python.migration.runner import _split_statements
sql = "CREATE TABLE x (id int)\n-- note: drop; then re-add\n;\nSELECT 1;"
stmts = [s for s in _split_statements(sql) if s.strip()]
assert len(stmts) == 2, f"semicolon in -- comment broke the split: {stmts!r}"

Today returns 3+ fragments (split at the ; inside the comment); 2 after the fix.

Suggested fix

Strip ---to-EOL comments before splitting (the $$/// blocks are already placeholders, so this won't touch them):

clean = re.sub(r"/\*.*?\*/", "", processed, flags=re.DOTALL)
clean = re.sub(r"--[^\n]*", "", clean)       # NEW: strip line comments first
for stmt in clean.split(delimiter):          # then split on ';'
    ...                                      # (the now-redundant per-line '--' handling can go)