fix: format code and mark doc examples as ignore for doctest

Author: GaneshPatil7517

datafusion/functions-aggregate/src/percentile_cont.rs

@@ -812,12 +812,8 @@ impl<T: ArrowNumericType + Debug> Accumulator for DistinctPercentileContAccumula
     }
 
     fn evaluate(&mut self) -> Result<ScalarValue> {
-        let mut values: Vec<T::Native> = self
-            .distinct_values
-            .values
-            .iter()
-            .map(|v| v.0)
-            .collect();
+        let mut values: Vec<T::Native> =
+            self.distinct_values.values.iter().map(|v| v.0).collect();
         let value = calculate_percentile::<T>(&mut values, self.percentile);
         ScalarValue::new_primitive::<T>(value, &self.data_type)
     }

datafusion/functions-aggregate/src/string_agg.rs

@@ -385,7 +385,9 @@ impl Accumulator for SimpleStringAggAccumulator {
 
     fn evaluate(&mut self) -> Result<ScalarValue> {
         if self.has_value {
-            Ok(ScalarValue::LargeUtf8(Some(self.accumulated_string.clone())))
+            Ok(ScalarValue::LargeUtf8(Some(
+                self.accumulated_string.clone(),
+            )))
         } else {
             Ok(ScalarValue::LargeUtf8(None))
         }

docs/source/library-user-guide/functions/adding-udfs.md

@@ -1366,7 +1366,7 @@ This is critical because:
 
 **Incorrect implementation** (consumes state):
 
-```rust
+```rust,ignore
 fn evaluate(&mut self) -> Result<ScalarValue> {
     // BAD: std::mem::take() consumes the values, leaving an empty Vec
     let values = std::mem::take(&mut self.values);
@@ -1378,7 +1378,7 @@ fn evaluate(&mut self) -> Result<ScalarValue> {
 
 **Correct implementation** (preserves state):
 
-```rust
+```rust,ignore
 fn evaluate(&mut self) -> Result<ScalarValue> {
     // GOOD: Use a reference or clone to preserve state
     calculate_result(&mut self.values)
@@ -1391,7 +1391,7 @@ fn evaluate(&mut self) -> Result<ScalarValue> {
 For more efficient sliding window calculations, you can implement the `retract_batch` method.
 This allows DataFusion to remove values that have "left" the window frame instead of recalculating from scratch:
 
-```rust
+```rust,ignore
 impl Accumulator for MyAccumulator {
     fn retract_batch(&mut self, values: &[ArrayRef]) -> Result<()> {
         // Remove the given values from the accumulator state