unify pystr py_pad

Author: youknowone

vm/src/obj/objbyteinner.rs

@@ -1246,7 +1246,12 @@ const ASCII_WHITESPACES: [u8; 6] = [0x20, 0x09, 0x0a, 0x0c, 0x0d, 0x0b];
 
 impl<'s> PyCommonString<'s, u8> for [u8] {
     type Container = Vec<u8>;
-    type CharIter = std::iter::Map<std::slice::Iter<'s, u8>, fn(&u8) -> char>;
+    type CharIter = bstr::Chars<'s>;
+    type ElementIter = std::iter::Copied<std::slice::Iter<'s, u8>>;
+
+    fn element_bytes_len(_: u8) -> usize {
+        1
+    }
 
     fn to_container(&self) -> Self::Container {
         self.to_vec()
@@ -1257,7 +1262,11 @@ impl<'s> PyCommonString<'s, u8> for [u8] {
     }
 
     fn chars(&'s self) -> Self::CharIter {
-        self.iter().map(|c| *c as char)
+        bstr::ByteSlice::chars(self)
+    }
+
+    fn elements(&'s self) -> Self::ElementIter {
+        self.iter().copied()
     }
 
     fn get_bytes<'a>(&'a self, range: std::ops::Range<usize>) -> &'a Self {
@@ -1325,12 +1334,4 @@ impl<'s> PyCommonString<'s, u8> for [u8] {
         }
         splited
     }
-
-    fn py_pad(&self, left: usize, right: usize, fill: u8) -> Self::Container {
-        let mut u = Vec::with_capacity(left + self.len() + right);
-        u.extend(std::iter::repeat(fill).take(left));
-        u.extend_from_slice(self);
-        u.extend(std::iter::repeat(fill).take(right));
-        u
-    }
 }

vm/src/obj/objstr.rs

@@ -1714,6 +1714,11 @@ impl PyCommonStringContainer<str> for String {
 impl<'s> PyCommonString<'s, char> for str {
     type Container = String;
     type CharIter = std::str::Chars<'s>;
+    type ElementIter = std::str::Chars<'s>;
+
+    fn element_bytes_len(c: char) -> usize {
+        c.len_utf8()
+    }
 
     fn to_container(&self) -> Self::Container {
         self.to_owned()
@@ -1727,6 +1732,10 @@ impl<'s> PyCommonString<'s, char> for str {
         str::chars(self)
     }
 
+    fn elements(&'s self) -> Self::ElementIter {
+        str::chars(self)
+    }
+
     fn get_bytes<'a>(&'a self, range: std::ops::Range<usize>) -> &'a Self {
         &self[range]
     }
@@ -1807,12 +1816,4 @@ impl<'s> PyCommonString<'s, char> for str {
         }
         splited
     }
-
-    fn py_pad(&self, left: usize, right: usize, fill: char) -> Self::Container {
-        let mut u = String::with_capacity((left + right) * fill.len_utf8() + self.len());
-        u.extend(std::iter::repeat(fill).take(left));
-        u.push_str(self);
-        u.extend(std::iter::repeat(fill).take(right));
-        u
-    }
 }

vm/src/obj/pystr.rs

@@ -9,6 +9,7 @@ pub struct SplitArgs<'a, T, S, E>
 where
     T: TryFromObject + PyCommonStringWrapper<S>,
     S: ?Sized + PyCommonString<'a, E>,
+    E: Copy,
 {
     #[pyarg(positional_or_keyword, default = "None")]
     sep: Option<T>,
@@ -22,6 +23,7 @@ impl<'a, T, S, E> SplitArgs<'a, T, S, E>
 where
     T: TryFromObject + PyCommonStringWrapper<S>,
     S: ?Sized + PyCommonString<'a, E>,
+    E: Copy,
 {
     pub fn get_value(self, vm: &VirtualMachine) -> PyResult<(Option<T>, isize)> {
         let sep = if let Some(s) = self.sep {
@@ -136,16 +138,22 @@ where
 
 pub trait PyCommonString<'s, E>
 where
+    E: Copy,
     Self: 's,
-    Self::Container: PyCommonStringContainer<Self>,
+    Self::Container: PyCommonStringContainer<Self> + std::iter::Extend<E>,
     Self::CharIter: 's + std::iter::Iterator<Item = char>,
+    Self::ElementIter: 's + std::iter::Iterator<Item = E>,
 {
     type Container;
     type CharIter;
+    type ElementIter;
+
+    fn element_bytes_len(c: E) -> usize;
 
     fn to_container(&self) -> Self::Container;
     fn as_bytes(&self) -> &[u8];
     fn chars(&'s self) -> Self::CharIter;
+    fn elements(&'s self) -> Self::ElementIter;
     fn get_bytes<'a>(&'a self, range: std::ops::Range<usize>) -> &'a Self;
     // FIXME: get_chars is expensive for str
     fn get_chars<'a>(&'a self, range: std::ops::Range<usize>) -> &'a Self;
@@ -273,7 +281,15 @@ where
         }
     }
 
-    fn py_pad(&self, left: usize, right: usize, fillchar: E) -> Self::Container;
+    fn py_pad(&self, left: usize, right: usize, fillchar: E) -> Self::Container {
+        let mut u = Self::Container::with_capacity(
+            (left + right) * Self::element_bytes_len(fillchar) + self.bytes_len(),
+        );
+        u.extend(std::iter::repeat(fillchar).take(left));
+        u.push_str(self);
+        u.extend(std::iter::repeat(fillchar).take(right));
+        u
+    }
 
     fn py_center(&self, width: usize, fillchar: E) -> Self::Container {
         let marg = width - self.chars_len();