fix(workflows): preserve commas inside quoted list-literal elements (#3134)

* fix(workflows): preserve commas inside quoted list-literal elements

The simple-expression evaluator parsed a list literal with a naive
`inner.split(",")`, which splits on commas inside quoted strings (and
nested brackets). So `{{ ["a, b", "c"] }}` evaluated to three items
(`["a", "b", "c"]`) instead of two, silently corrupting `fan-out` `items:`
and any list expression that contains a comma inside a quoted element.

Split list-literal elements on top-level commas only, ignoring commas
inside quotes or nested brackets, via a small `_split_top_level_commas`
helper. Plain and empty lists are unchanged.

Add tests covering quoted commas, nested lists, and the existing
plain/empty cases.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* test(workflows): cover single-quoted and nested list literals

Address review: extend the list-literal regression test to assert single-quoted elements with commas and nested lists parse correctly, alongside the existing double-quoted cases.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/specify_cli/workflows/expressions.py

@@ -146,6 +146,40 @@ def _build_namespace(context: Any) -> dict[str, Any]:
     return ns
 
 
+def _split_top_level_commas(text: str) -> list[str]:
+    """Split *text* on commas that are not inside quotes or nested brackets.
+
+    Used for list-literal elements so a quoted element containing a comma
+    (e.g. ``["a, b", "c"]``) is not split mid-string, and nested lists/calls
+    (e.g. ``[[1, 2], 3]``) are kept intact.
+    """
+    parts: list[str] = []
+    buf: list[str] = []
+    quote: str | None = None
+    depth = 0
+    for ch in text:
+        if quote is not None:
+            buf.append(ch)
+            if ch == quote:
+                quote = None
+        elif ch in ("'", '"'):
+            quote = ch
+            buf.append(ch)
+        elif ch in "([{":
+            depth += 1
+            buf.append(ch)
+        elif ch in ")]}":
+            depth = max(0, depth - 1)
+            buf.append(ch)
+        elif ch == "," and depth == 0:
+            parts.append("".join(buf))
+            buf = []
+        else:
+            buf.append(ch)
+    parts.append("".join(buf))
+    return parts
+
+
 def _evaluate_simple_expression(expr: str, namespace: dict[str, Any]) -> Any:
     """Evaluate a simple expression against the namespace.
 
@@ -291,7 +325,10 @@ def _evaluate_simple_expression(expr: str, namespace: dict[str, Any]) -> Any:
         inner = expr[1:-1].strip()
         if not inner:
             return []
-        items = [_evaluate_simple_expression(i.strip(), namespace) for i in inner.split(",")]
+        items = [
+            _evaluate_simple_expression(i.strip(), namespace)
+            for i in _split_top_level_commas(inner)
+        ]
         return items
 
     # Variable reference (dot-path)

tests/test_workflows.py

@@ -268,6 +268,24 @@ class TestExpressions:
         ctx = StepContext(inputs={"a": False, "b": True})
         assert evaluate_expression("{{ inputs.a or inputs.b }}", ctx) is True
 
+    def test_list_literal_preserves_quoted_commas(self):
+        from specify_cli.workflows.expressions import evaluate_expression
+        from specify_cli.workflows.base import StepContext
+
+        ctx = StepContext()
+        # commas inside a double-quoted element must not split it
+        assert evaluate_expression('{{ ["a, b", "c"] }}', ctx) == ["a, b", "c"]
+        assert evaluate_expression('{{ ["x, y, z"] }}', ctx) == ["x, y, z"]
+        # single-quoted elements are handled the same way
+        assert evaluate_expression("{{ ['a, b', 'c'] }}", ctx) == ["a, b", "c"]
+        assert evaluate_expression("{{ ['p, q, r'] }}", ctx) == ["p, q, r"]
+        # plain and empty lists still parse correctly
+        assert evaluate_expression("{{ [1, 2, 3] }}", ctx) == [1, 2, 3]
+        assert evaluate_expression("{{ [] }}", ctx) == []
+        # nested lists (commas inside the inner brackets) stay intact
+        assert evaluate_expression('{{ [["a", "b"], "c"] }}', ctx) == [["a", "b"], "c"]
+        assert evaluate_expression("{{ [[1, 2], [3, 4]] }}", ctx) == [[1, 2], [3, 4]]
+
     def test_filter_default(self):
         from specify_cli.workflows.expressions import evaluate_expression
         from specify_cli.workflows.base import StepContext