fix(struct-column): make ops.StructColumn dshape depend on its input

ibis/backends/clickhouse/compiler/values.py

@@ -409,7 +409,7 @@ def _log(op, **kw):
 @translate_val.register(tuple)
 def _node_list(op, **kw):
     values = ", ".join(map(_sql, map(partial(translate_val, **kw), op)))
-    return f"({values})"
+    return f"tuple({values})"
 
 
 def _interval_format(op):

ibis/backends/tests/test_struct.py

@@ -88,3 +88,25 @@ def test_struct_column(alltypes, df):
         name="s",
     )
     tm.assert_series_equal(result, expected)
+
+
+@pytest.mark.notimpl(["dask", "pandas", "postgres", "polars"])
+def test_collect_into_struct(alltypes):
+    from ibis import _
+
+    t = alltypes
+    expr = (
+        t[_.string_col.isin(("0", "1"))]
+        .group_by(group="string_col")
+        .agg(
+            val=lambda t: ibis.struct(
+                dict(key=t.bigint_col.collect().cast("!array<int64>"))
+            )
+        )
+    )
+    result = expr.execute()
+    assert result.shape == (2, 2)
+    assert set(result.group) == {"0", "1"}
+    val = result.val
+    assert len(val.loc[result.group == "0"].iat[0]["key"]) == 730
+    assert len(val.loc[result.group == "1"].iat[0]["key"]) == 730

ibis/expr/operations/structs.py

@@ -2,7 +2,6 @@
 
 from public import public
 
-import ibis.expr.datashape as ds
 import ibis.expr.datatypes as dt
 import ibis.expr.rules as rlz
 from ibis.common.annotations import attribute
@@ -33,7 +32,7 @@ class StructColumn(Value):
     names: VarTuple[str]
     values: VarTuple[Value]
 
-    shape = ds.columnar
+    shape = rlz.shape_like("values")
 
     @attribute.default
     def dtype(self) -> dt.DataType:

ibis/expr/operations/tests/test_structs.py

@@ -0,0 +1,19 @@
+from __future__ import annotations
+
+import ibis
+import ibis.expr.datashape as ds
+import ibis.expr.datatypes as dt
+import ibis.expr.operations as ops
+
+
+def test_struct_column_shape():
+    one = ops.Literal(1, dtype=dt.int64)
+    op = ops.StructColumn(names=("a",), values=(one,))
+
+    assert op.shape == ds.scalar
+
+    col = ops.TableColumn(
+        ops.UnboundTable(schema=ibis.schema(dict(a="int64")), name="t"), "a"
+    )
+    op = ops.StructColumn(names=("a",), values=(col,))
+    assert op.shape == ds.columnar