move the Log, Power functions to datafusion-functions (#9983)

* move the Log, Power functions to datafusion-functions

* match type instead of name

* fix formatting errors

datafusion/core/tests/simplification.rs

@@ -25,6 +25,7 @@ use datafusion_common::cast::as_int32_array;
 use datafusion_common::ScalarValue;
 use datafusion_common::{DFSchemaRef, ToDFSchema};
 use datafusion_expr::expr::ScalarFunction;
+use datafusion_expr::logical_plan::builder::table_scan_with_filters;
 use datafusion_expr::simplify::SimplifyInfo;
 use datafusion_expr::{
     expr, table_scan, BuiltinScalarFunction, Cast, ColumnarValue, Expr, ExprSchemable,
@@ -294,6 +295,45 @@ fn select_date_plus_interval() -> Result<()> {
     Ok(())
 }
 
+#[test]
+fn simplify_project_scalar_fn() -> Result<()> {
+    // Issue https://github.com/apache/arrow-datafusion/issues/5996
+    let schema = Schema::new(vec![Field::new("f", DataType::Float64, false)]);
+    let plan = table_scan(Some("test"), &schema, None)?
+        .project(vec![power(col("f"), lit(1.0))])?
+        .build()?;
+
+    // before simplify: power(t.f, 1.0)
+    // after simplify:  t.f as "power(t.f, 1.0)"
+    let expected = "Projection: test.f AS power(test.f,Float64(1))\
+                      \n  TableScan: test";
+    let actual = get_optimized_plan_formatted(&plan, &Utc::now());
+    assert_eq!(expected, actual);
+    Ok(())
+}
+
+#[test]
+fn simplify_scan_predicate() -> Result<()> {
+    let schema = Schema::new(vec![
+        Field::new("f", DataType::Float64, false),
+        Field::new("g", DataType::Float64, false),
+    ]);
+    let plan = table_scan_with_filters(
+        Some("test"),
+        &schema,
+        None,
+        vec![col("g").eq(power(col("f"), lit(1.0)))],
+    )?
+    .build()?;
+
+    // before simplify: t.g = power(t.f, 1.0)
+    // after simplify:  (t.g = t.f) as "t.g = power(t.f, 1.0)"
+    let expected = "TableScan: test, full_filters=[g = f AS g = power(f,Float64(1))]";
+    let actual = get_optimized_plan_formatted(&plan, &Utc::now());
+    assert_eq!(expected, actual);
+    Ok(())
+}
+
 #[test]
 fn test_const_evaluator() {
     // true --> true
@@ -431,3 +471,99 @@ fn multiple_now() -> Result<()> {
     assert_eq!(expected, actual);
     Ok(())
 }
+
+// ------------------------------
+// --- Simplifier tests -----
+// ------------------------------
+
+fn expr_test_schema() -> DFSchemaRef {
+    Schema::new(vec![
+        Field::new("c1", DataType::Utf8, true),
+        Field::new("c2", DataType::Boolean, true),
+        Field::new("c3", DataType::Int64, true),
+        Field::new("c4", DataType::UInt32, true),
+        Field::new("c1_non_null", DataType::Utf8, false),
+        Field::new("c2_non_null", DataType::Boolean, false),
+        Field::new("c3_non_null", DataType::Int64, false),
+        Field::new("c4_non_null", DataType::UInt32, false),
+    ])
+    .to_dfschema_ref()
+    .unwrap()
+}
+
+fn test_simplify(input_expr: Expr, expected_expr: Expr) {
+    let info: MyInfo = MyInfo {
+        schema: expr_test_schema(),
+        execution_props: ExecutionProps::new(),
+    };
+    let simplifier = ExprSimplifier::new(info);
+    let simplified_expr = simplifier
+        .simplify(input_expr.clone())
+        .expect("successfully evaluated");
+
+    assert_eq!(
+        simplified_expr, expected_expr,
+        "Mismatch evaluating {input_expr}\n  Expected:{expected_expr}\n  Got:{simplified_expr}"
+    );
+}
+
+#[test]
+fn test_simplify_log() {
+    // Log(c3, 1) ===> 0
+    {
+        let expr = log(col("c3_non_null"), lit(1));
+        test_simplify(expr, lit(0i64));
+    }
+    // Log(c3, c3) ===> 1
+    {
+        let expr = log(col("c3_non_null"), col("c3_non_null"));
+        let expected = lit(1i64);
+        test_simplify(expr, expected);
+    }
+    // Log(c3, Power(c3, c4)) ===> c4
+    {
+        let expr = log(
+            col("c3_non_null"),
+            power(col("c3_non_null"), col("c4_non_null")),
+        );
+        let expected = col("c4_non_null");
+        test_simplify(expr, expected);
+    }
+    // Log(c3, c4) ===> Log(c3, c4)
+    {
+        let expr = log(col("c3_non_null"), col("c4_non_null"));
+        let expected = log(col("c3_non_null"), col("c4_non_null"));
+        test_simplify(expr, expected);
+    }
+}
+
+#[test]
+fn test_simplify_power() {
+    // Power(c3, 0) ===> 1
+    {
+        let expr = power(col("c3_non_null"), lit(0));
+        let expected = lit(1i64);
+        test_simplify(expr, expected)
+    }
+    // Power(c3, 1) ===> c3
+    {
+        let expr = power(col("c3_non_null"), lit(1));
+        let expected = col("c3_non_null");
+        test_simplify(expr, expected)
+    }
+    // Power(c3, Log(c3, c4)) ===> c4
+    {
+        let expr = power(
+            col("c3_non_null"),
+            log(col("c3_non_null"), col("c4_non_null")),
+        );
+        let expected = col("c4_non_null");
+        test_simplify(expr, expected)
+    }
+    // Power(c3, c4) ===> Power(c3, c4)
+    {
+        let expr = power(col("c3_non_null"), col("c4_non_null"));
+        let expected = power(col("c3_non_null"), col("c4_non_null"));
+        test_simplify(expr, expected)
+    }
+}

datafusion/expr/src/built_in_function.rs

@@ -47,12 +47,8 @@ pub enum BuiltinScalarFunction {
     Factorial,
     /// iszero
     Iszero,
-    /// log, same as log10
-    Log,
     /// nanvl
     Nanvl,
-    /// power
-    Power,
     /// round
     Round,
     /// trunc
@@ -128,9 +124,7 @@ impl BuiltinScalarFunction {
             BuiltinScalarFunction::Exp => Volatility::Immutable,
             BuiltinScalarFunction::Factorial => Volatility::Immutable,
             BuiltinScalarFunction::Iszero => Volatility::Immutable,
-            BuiltinScalarFunction::Log => Volatility::Immutable,
             BuiltinScalarFunction::Nanvl => Volatility::Immutable,
-            BuiltinScalarFunction::Power => Volatility::Immutable,
             BuiltinScalarFunction::Round => Volatility::Immutable,
             BuiltinScalarFunction::Cot => Volatility::Immutable,
             BuiltinScalarFunction::Trunc => Volatility::Immutable,
@@ -176,16 +170,6 @@ impl BuiltinScalarFunction {
 
             BuiltinScalarFunction::Factorial => Ok(Int64),
 
-            BuiltinScalarFunction::Power => match &input_expr_types[0] {
-                Int64 => Ok(Int64),
-                _ => Ok(Float64),
-            },
-
-            BuiltinScalarFunction::Log => match &input_expr_types[0] {
-                Float32 => Ok(Float32),
-                _ => Ok(Float64),
-            },
-
             BuiltinScalarFunction::Nanvl => match &input_expr_types[0] {
                 Float32 => Ok(Float32),
                 _ => Ok(Float64),
@@ -233,10 +217,6 @@ impl BuiltinScalarFunction {
                 self.volatility(),
             ),
             BuiltinScalarFunction::Random => Signature::exact(vec![], self.volatility()),
-            BuiltinScalarFunction::Power => Signature::one_of(
-                vec![Exact(vec![Int64, Int64]), Exact(vec![Float64, Float64])],
-                self.volatility(),
-            ),
             BuiltinScalarFunction::Round => Signature::one_of(
                 vec![
                     Exact(vec![Float64, Int64]),
@@ -255,16 +235,6 @@ impl BuiltinScalarFunction {
                 ],
                 self.volatility(),
             ),
-
-            BuiltinScalarFunction::Log => Signature::one_of(
-                vec![
-                    Exact(vec![Float32]),
-                    Exact(vec![Float64]),
-                    Exact(vec![Float32, Float32]),
-                    Exact(vec![Float64, Float64]),
-                ],
-                self.volatility(),
-            ),
             BuiltinScalarFunction::Nanvl => Signature::one_of(
                 vec![Exact(vec![Float32, Float32]), Exact(vec![Float64, Float64])],
                 self.volatility(),
@@ -302,8 +272,6 @@ impl BuiltinScalarFunction {
                 | BuiltinScalarFunction::Trunc
         ) {
             Some(vec![Some(true)])
-        } else if *self == BuiltinScalarFunction::Log {
-            Some(vec![Some(true), Some(false)])
         } else {
             None
         }
@@ -317,9 +285,7 @@ impl BuiltinScalarFunction {
             BuiltinScalarFunction::Exp => &["exp"],
             BuiltinScalarFunction::Factorial => &["factorial"],
             BuiltinScalarFunction::Iszero => &["iszero"],
-            BuiltinScalarFunction::Log => &["log"],
             BuiltinScalarFunction::Nanvl => &["nanvl"],
-            BuiltinScalarFunction::Power => &["power", "pow"],
             BuiltinScalarFunction::Random => &["random"],
             BuiltinScalarFunction::Round => &["round"],
             BuiltinScalarFunction::Trunc => &["trunc"],

datafusion/expr/src/expr_fn.rs

@@ -546,9 +546,6 @@ nary_scalar_expr!(
 );
 scalar_expr!(Exp, exp, num, "exponential");
 
-scalar_expr!(Power, power, base exponent, "`base` raised to the power of `exponent`");
-scalar_expr!(Log, log, base x, "logarithm of a `x` for a particular `base`");
-
 scalar_expr!(InitCap, initcap, string, "converts the first letter of each word in `string` in uppercase and the remaining characters in lowercase");
 scalar_expr!(EndsWith, ends_with, string suffix, "whether the `string` ends with the `suffix`");
 nary_scalar_expr!(Coalesce, coalesce, "returns `coalesce(args...)`, which evaluates to the value of the first [Expr] which is not NULL");

datafusion/functions/src/macros.rs

@@ -357,6 +357,19 @@ macro_rules! make_math_binary_udf {
     };
 }
 
+macro_rules! make_function_scalar_inputs {
+    ($ARG: expr, $NAME:expr, $ARRAY_TYPE:ident, $FUNC: block) => {{
+        let arg = downcast_arg!($ARG, $NAME, $ARRAY_TYPE);
+
+        arg.iter()
+            .map(|a| match a {
+                Some(a) => Some($FUNC(a)),
+                _ => None,
+            })
+            .collect::<$ARRAY_TYPE>()
+    }};
+}
+
 macro_rules! make_function_inputs2 {
     ($ARG1: expr, $ARG2: expr, $NAME1:expr, $NAME2: expr, $ARRAY_TYPE:ident, $FUNC: block) => {{
         let arg1 = downcast_arg!($ARG1, $NAME1, $ARRAY_TYPE);