add a hleper function to list all sql functions

daft/daft/__init__.pyi

@@ -1195,8 +1195,13 @@ def minhash(
     ngram_size: int,
     seed: int = 1,
 ) -> PyExpr: ...
+
+# -----
+# SQL functions
+# -----
 def sql(sql: str, catalog: PyCatalog, daft_planning_config: PyDaftPlanningConfig) -> LogicalPlanBuilder: ...
 def sql_expr(sql: str) -> PyExpr: ...
+def list_sql_functions() -> list[str]: ...
 def utf8_count_matches(expr: PyExpr, patterns: PyExpr, whole_words: bool, case_sensitive: bool) -> PyExpr: ...
 def to_struct(inputs: list[PyExpr]) -> PyExpr: ...
 

src/daft-sql/src/functions.rs

@@ -14,7 +14,7 @@ use crate::{
 };
 
 /// [SQL_FUNCTIONS] is a singleton that holds all the registered SQL functions.
-static SQL_FUNCTIONS: Lazy<SQLFunctions> = Lazy::new(|| {
+pub(crate) static SQL_FUNCTIONS: Lazy<SQLFunctions> = Lazy::new(|| {
     let mut functions = SQLFunctions::new();
     functions.register::<SQLModuleAggs>();
     functions.register::<SQLModuleFloat>();
@@ -88,7 +88,7 @@ pub trait SQLFunction: Send + Sync {
 ///   - Use multimap for function variants.
 ///   - Add more functions..
 pub struct SQLFunctions {
-    map: HashMap<String, Arc<dyn SQLFunction>>,
+    pub(crate) map: HashMap<String, Arc<dyn SQLFunction>>,
 }
 
 pub(crate) struct SQLFunctionArguments {

src/daft-sql/src/lib.rs

@@ -15,6 +15,7 @@ pub fn register_modules(parent: &Bound<PyModule>) -> PyResult<()> {
     parent.add_class::<python::PyCatalog>()?;
     parent.add_function(wrap_pyfunction_bound!(python::sql, parent)?)?;
     parent.add_function(wrap_pyfunction_bound!(python::sql_expr, parent)?)?;
+    parent.add_function(wrap_pyfunction_bound!(python::list_sql_functions, parent)?)?;
     Ok(())
 }
 

src/daft-sql/src/python.rs

@@ -3,7 +3,7 @@ use daft_dsl::python::PyExpr;
 use daft_plan::{LogicalPlanBuilder, PyLogicalPlanBuilder};
 use pyo3::prelude::*;
 
-use crate::{catalog::SQLCatalog, planner::SQLPlanner};
+use crate::{catalog::SQLCatalog, functions::SQL_FUNCTIONS, planner::SQLPlanner};
 
 #[pyfunction]
 pub fn sql(
@@ -22,6 +22,11 @@ pub fn sql_expr(sql: &str) -> PyResult<PyExpr> {
     Ok(PyExpr { expr })
 }
 
+#[pyfunction]
+pub fn list_sql_functions() -> Vec<String> {
+    SQL_FUNCTIONS.map.keys().cloned().collect()
+}
+
 /// PyCatalog is the Python interface to the Catalog.
 #[pyclass(module = "daft.daft")]
 #[derive(Debug, Clone)]