Refactored (internal) fmt (#842)

* Refactored fmt

* More tests

src/array/binary/fmt.rs

@@ -0,0 +1,26 @@
+use std::fmt::{Debug, Formatter, Result, Write};
+
+use super::super::fmt::write_vec;
+use super::super::Offset;
+use super::BinaryArray;
+
+pub fn write_value<O: Offset, W: Write>(array: &BinaryArray<O>, index: usize, f: &mut W) -> Result {
+    let bytes = array.value(index);
+    let writer = |f: &mut W, index| write!(f, "{}", bytes[index]);
+
+    write_vec(f, writer, None, bytes.len(), "None", false)
+}
+
+impl<O: Offset> Debug for BinaryArray<O> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        let writer = |f: &mut Formatter, index| write_value(self, index, f);
+
+        let head = if O::is_large() {
+            "LargeBinaryArray"
+        } else {
+            "BinaryArray"
+        };
+        write!(f, "{}", head)?;
+        write_vec(f, writer, self.validity(), self.len(), "None", false)
+    }
+}

src/array/binary/mod.rs

@@ -6,12 +6,12 @@ use crate::{
 };
 
 use super::{
-    display_fmt, display_helper,
     specification::{check_offsets_minimal, try_check_offsets},
     Array, GenericBinaryArray, Offset,
 };
 
 mod ffi;
+pub(super) mod fmt;
 mod iterator;
 pub use iterator::*;
 mod from;
@@ -23,7 +23,7 @@ pub use mutable::*;
 /// The following invariants hold:
 /// * Two consecutives `offsets` casted (`as`) to `usize` are valid slices of `values`.
 /// * `len` is equal to `validity.len()`, when defined.
-#[derive(Debug, Clone)]
+#[derive(Clone)]
 pub struct BinaryArray<O: Offset> {
     data_type: DataType,
     offsets: Buffer<O>,
@@ -274,19 +274,6 @@ impl<O: Offset> Array for BinaryArray<O> {
     }
 }
 
-impl<O: Offset> std::fmt::Display for BinaryArray<O> {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let a = |x: &[u8]| display_helper(x.iter().map(|x| Some(format!("{:b}", x)))).join(" ");
-        let iter = self.iter().map(|x| x.map(a));
-        let head = if O::is_large() {
-            "LargeBinaryArray"
-        } else {
-            "BinaryArray"
-        };
-        display_fmt(iter, head, f, false)
-    }
-}
-
 unsafe impl<O: Offset> GenericBinaryArray<O> for BinaryArray<O> {
     #[inline]
     fn values(&self) -> &[u8] {

src/array/boolean/fmt.rs

@@ -0,0 +1,17 @@
+use std::fmt::{Debug, Formatter, Result, Write};
+
+use super::super::fmt::write_vec;
+use super::BooleanArray;
+
+pub fn write_value<W: Write>(array: &BooleanArray, index: usize, f: &mut W) -> Result {
+    write!(f, "{}", array.value(index))
+}
+
+impl Debug for BooleanArray {
+    fn fmt(&self, f: &mut Formatter) -> Result {
+        let writer = |f: &mut Formatter, index| write_value(self, index, f);
+
+        write!(f, "BooleanArray")?;
+        write_vec(f, writer, self.validity(), self.len(), "None", false)
+    }
+}

src/array/boolean/mod.rs

@@ -4,9 +4,10 @@ use crate::{
 };
 use either::Either;
 
-use super::{display_fmt, Array};
+use super::Array;
 
 mod ffi;
+pub(super) mod fmt;
 mod from;
 mod iterator;
 mod mutable;
@@ -204,9 +205,3 @@ impl Array for BooleanArray {
         Box::new(self.with_validity(validity))
     }
 }
-
-impl std::fmt::Debug for BooleanArray {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        display_fmt(self.iter(), "BooleanArray", f, false)
-    }
-}

src/array/dictionary/fmt.rs

@@ -0,0 +1,32 @@
+use std::fmt::{Debug, Formatter, Result, Write};
+
+use crate::array::Array;
+
+use super::super::fmt::{get_display, write_vec};
+use super::{DictionaryArray, DictionaryKey};
+
+pub fn write_value<K: DictionaryKey, W: Write>(
+    array: &DictionaryArray<K>,
+    index: usize,
+    null: &'static str,
+    f: &mut W,
+) -> Result {
+    let keys = array.keys();
+    let values = array.values();
+
+    if keys.is_valid(index) {
+        let key = keys.value(index).to_usize().unwrap();
+        get_display(values.as_ref(), null)(f, key)
+    } else {
+        write!(f, "{}", null)
+    }
+}
+
+impl<K: DictionaryKey> Debug for DictionaryArray<K> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        let writer = |f: &mut Formatter, index| write_value(self, index, "None", f);
+
+        write!(f, "DictionaryArray")?;
+        write_vec(f, writer, self.validity(), self.len(), "None", false)
+    }
+}

src/array/dictionary/mod.rs

@@ -8,13 +8,13 @@ use crate::{
 };
 
 mod ffi;
+pub(super) mod fmt;
 mod iterator;
 mod mutable;
 pub use iterator::*;
 pub use mutable::*;
 
-use super::display::get_value_display;
-use super::{display_fmt, new_empty_array, primitive::PrimitiveArray, Array};
+use super::{new_empty_array, primitive::PrimitiveArray, Array};
 use crate::scalar::NullScalar;
 
 /// Trait denoting [`NativeType`]s that can be used as keys of a dictionary.
@@ -50,7 +50,7 @@ impl DictionaryKey for u64 {
 
 /// An [`Array`] whose values are encoded by keys. This [`Array`] is useful when the cardinality of
 /// values is low compared to the length of the [`Array`].
-#[derive(Debug, Clone)]
+#[derive(Clone)]
 pub struct DictionaryArray<K: DictionaryKey> {
     data_type: DataType,
     keys: PrimitiveArray<K>,
@@ -203,16 +203,3 @@ impl<K: DictionaryKey> Array for DictionaryArray<K> {
         Box::new(self.with_validity(validity))
     }
 }
-
-impl<K: DictionaryKey> std::fmt::Display for DictionaryArray<K>
-where
-    PrimitiveArray<K>: std::fmt::Display,
-{
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let display = get_value_display(self);
-        let new_lines = false;
-        let head = &format!("{:?}", self.data_type());
-        let iter = self.iter().enumerate().map(|(i, x)| x.map(|_| display(i)));
-        display_fmt(iter, head, f, new_lines)
-    }
-}