minor: fix cargo clippy some warning

datafusion/common/src/parsers.rs

@@ -17,6 +17,7 @@
 
 //! Interval parsing logic
 use sqlparser::parser::ParserError;
+use std::fmt::Display;
 
 use std::result;
 use std::str::FromStr;
@@ -54,16 +55,16 @@ impl FromStr for CompressionTypeVariant {
     }
 }
 
-impl ToString for CompressionTypeVariant {
-    fn to_string(&self) -> String {
-        match self {
+impl Display for CompressionTypeVariant {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let str = match self {
             Self::GZIP => "GZIP",
             Self::BZIP2 => "BZIP2",
             Self::XZ => "XZ",
             Self::ZSTD => "ZSTD",
             Self::UNCOMPRESSED => "",
-        }
-        .to_string()
+        };
+        write!(f, "{}", str)
     }
 }
 

datafusion/physical-expr/src/equivalence/ordering.rs

@@ -479,7 +479,7 @@ mod tests {
                 vec![
                     (col_a, options),
                     (col_c, options),
-                    (&floor_a, options),
+                    (floor_a, options),
                     (&a_plus_b, options),
                 ],
                 // expected: requirement is not satisfied.
@@ -505,8 +505,8 @@ mod tests {
                 vec![
                     (col_a, options),
                     (col_b, options),
-                    (&col_c, options),
-                    (&floor_a, options),
+                    (col_c, options),
+                    (floor_a, options),
                 ],
                 // expected: requirement is satisfied.
                 true,

datafusion/physical-expr/src/equivalence/projection.rs

@@ -283,7 +283,7 @@ mod tests {
                 // orderings
                 vec![
                     // [a + b ASC, c ASC]
-                    vec![(&a_plus_b, option_asc), (&col_c, option_asc)],
+                    vec![(&a_plus_b, option_asc), (col_c, option_asc)],
                 ],
                 // projection exprs
                 vec![
@@ -546,7 +546,7 @@ mod tests {
                     vec![
                         (col_a, option_asc),
                         (col_c, option_asc),
-                        (&col_b, option_asc),
+                        (col_b, option_asc),
                     ],
                 ],
                 // proj exprs
@@ -805,7 +805,7 @@ mod tests {
                     // [a+b ASC, round(c) ASC, c_new ASC]
                     vec![
                         (&a_new_plus_b_new, option_asc),
-                        (&col_round_c_res, option_asc),
+                        (col_round_c_res, option_asc),
                     ],
                     // [a+b ASC, c_new ASC]
                     vec![(&a_new_plus_b_new, option_asc), (col_c_new, option_asc)],

datafusion/physical-expr/src/execution_props.rs

@@ -99,7 +99,7 @@ impl ExecutionProps {
     ) -> Option<Arc<dyn VarProvider + Send + Sync>> {
         self.var_providers
             .as_ref()
-            .and_then(|var_providers| var_providers.get(&var_type).map(Arc::clone))
+            .and_then(|var_providers| var_providers.get(&var_type).cloned())
     }
 }
 

datafusion/sql/tests/sql_integration.rs

@@ -2881,11 +2881,11 @@ impl ContextProvider for MockContextProvider {
     }
 
     fn get_function_meta(&self, name: &str) -> Option<Arc<ScalarUDF>> {
-        self.udfs.get(name).map(Arc::clone)
+        self.udfs.get(name).cloned()
     }
 
     fn get_aggregate_meta(&self, name: &str) -> Option<Arc<AggregateUDF>> {
-        self.udafs.get(name).map(Arc::clone)
+        self.udafs.get(name).cloned()
     }
 
     fn get_variable_type(&self, _: &[String]) -> Option<DataType> {

datafusion/sqllogictest/src/engines/postgres_engine/types.rs

@@ -16,6 +16,7 @@
 // under the License.
 
 use postgres_types::Type;
+use std::fmt::Display;
 use tokio_postgres::types::FromSql;
 
 pub struct PgRegtype {
@@ -37,8 +38,8 @@ impl<'a> FromSql<'a> for PgRegtype {
     }
 }
 
-impl ToString for PgRegtype {
-    fn to_string(&self) -> String {
-        self.value.clone()
+impl Display for PgRegtype {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.value)
     }
 }