[FEAT] Support zero_lit in Rust/Python side

This commit also fixes a bug when converting struct literal to series

daft/__init__.py

@@ -73,7 +73,7 @@ def refresh_logger() -> None:
 from daft.dataframe import DataFrame
 from daft.logical.schema import Schema
 from daft.datatype import DataType, TimeUnit
-from daft.expressions import Expression, col, lit, interval
+from daft.expressions import Expression, col, lit, interval, zero_lit
 from daft.io import (
     DataCatalogTable,
     DataCatalogType,
@@ -120,6 +120,7 @@ def refresh_logger() -> None:
     "ImageMode",
     "ImageFormat",
     "lit",
+    "zero_lit",
     "Series",
     "TimeUnit",
     "register_viz_hook",

daft/daft/__init__.pyi

@@ -1135,6 +1135,7 @@ class PyExpr:
 def eq(expr1: PyExpr, expr2: PyExpr) -> bool: ...
 def col(name: str) -> PyExpr: ...
 def lit(item: Any) -> PyExpr: ...
+def zero_lit(dt: PyDataType) -> PyExpr: ...
 def date_lit(item: int) -> PyExpr: ...
 def time_lit(item: int, tu: PyTimeUnit) -> PyExpr: ...
 def timestamp_lit(item: int, tu: PyTimeUnit, tz: str | None) -> PyExpr: ...
@@ -1733,6 +1734,7 @@ class LogicalPlanBuilder:
         join_suffix: str | None = None,
     ) -> LogicalPlanBuilder: ...
     def concat(self, other: LogicalPlanBuilder) -> LogicalPlanBuilder: ...
+    def intersect(self, other: LogicalPlanBuilder, is_all: bool) -> LogicalPlanBuilder: ...
     def add_monotonically_increasing_id(self, column_name: str | None) -> LogicalPlanBuilder: ...
     def table_write(
         self,

daft/expressions/__init__.py

@@ -1,5 +1,5 @@
 from __future__ import annotations
 
-from .expressions import Expression, ExpressionsProjection, col, lit, interval
+from .expressions import Expression, ExpressionsProjection, col, lit, interval, zero_lit
 
-__all__ = ["Expression", "ExpressionsProjection", "col", "lit", "interval"]
+__all__ = ["Expression", "ExpressionsProjection", "col", "lit", "interval", "zero_lit"]

daft/expressions/expressions.py

@@ -36,6 +36,7 @@
 from daft.daft import tokenize_encode as _tokenize_encode
 from daft.daft import url_download as _url_download
 from daft.daft import utf8_count_matches as _utf8_count_matches
+from daft.daft import zero_lit as _zero_lit
 from daft.datatype import DataType, TimeUnit
 from daft.dependencies import pa
 from daft.expressions.testing import expr_structurally_equal
@@ -133,6 +134,39 @@ def lit(value: object) -> Expression:
     return Expression._from_pyexpr(lit_value)
 
 
+def zero_lit(dt: DataType) -> Expression:
+    """Creates a literal Expression representing a zero value of corresponding data type
+
+    Example:
+        >>> import daft
+        >>> from daft import DataType
+        >>> df = daft.from_pydict({"x": [1, 2, 3]})
+        >>> df = df.with_column("y", daft.zero_lit(DataType.int32()))
+        >>> df.show()
+        ╭───────┬───────╮
+        │ x     ┆ y     │
+        │ ---   ┆ ---   │
+        │ Int64 ┆ Int32 │
+        ╞═══════╪═══════╡
+        │ 1     ┆ 0     │
+        ├╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
+        │ 2     ┆ 0     │
+        ├╌╌╌╌╌╌╌┼╌╌╌╌╌╌╌┤
+        │ 3     ┆ 0     │
+        ╰───────┴───────╯
+        <BLANKLINE>
+        (Showing first 3 of 3 rows)
+
+    Args:
+        dt: data type of the zero value
+
+    Returns:
+         Expression: representing the zero value of the data type
+    """
+    zero = _zero_lit(dt._dtype)
+    return Expression._from_pyexpr(zero)
+
+
 def col(name: str) -> Expression:
     """Creates an Expression referring to the column with the provided name.
 

src/daft-dsl/src/lib.rs

@@ -18,7 +18,7 @@ pub use expr::{
     binary_op, col, has_agg, has_stateful_udf, is_partition_compatible, AggExpr,
     ApproxPercentileParams, Expr, ExprRef, Operator, SketchType,
 };
-pub use lit::{lit, literal_value, literals_to_series, null_lit, Literal, LiteralValue};
+pub use lit::{lit, literal_value, literals_to_series, null_lit, zero_lit, Literal, LiteralValue};
 #[cfg(feature = "python")]
 use pyo3::prelude::*;
 pub use resolve_expr::{
@@ -39,6 +39,7 @@ pub fn register_modules(parent: &Bound<PyModule>) -> PyResult<()> {
     parent.add_function(wrap_pyfunction_bound!(python::interval_lit, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(python::decimal_lit, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(python::series_lit, parent)?)?;
+    parent.add_function(wrap_pyfunction_bound!(python::zero_lit, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(python::stateless_udf, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(python::stateful_udf, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(