1 files changed, 178 insertions, 0 deletions
diff --git a/vendor/itertools/src/format.rs b/vendor/itertools/src/format.rs
new file mode 100644
index 00000000..3abdda36
--- /dev/null
+++ b/vendor/itertools/src/format.rs
@@ -0,0 +1,178 @@
+use std::cell::Cell;
+use std::fmt;
+
+/// Format all iterator elements lazily, separated by `sep`.
+///
+/// The format value can only be formatted once, after that the iterator is
+/// exhausted.
+///
+/// See [`.format_with()`](crate::Itertools::format_with) for more information.
+pub struct FormatWith<'a, I, F> {
+    sep: &'a str,
+    /// `FormatWith` uses interior mutability because `Display::fmt` takes `&self`.
+    inner: Cell<Option<(I, F)>>,
+}
+
+/// Format all iterator elements lazily, separated by `sep`.
+///
+/// The format value can only be formatted once, after that the iterator is
+/// exhausted.
+///
+/// See [`.format()`](crate::Itertools::format)
+/// for more information.
+pub struct Format<'a, I> {
+    sep: &'a str,
+    /// `Format` uses interior mutability because `Display::fmt` takes `&self`.
+    inner: Cell<Option<I>>,
+}
+
+pub fn new_format<I, F>(iter: I, separator: &str, f: F) -> FormatWith<'_, I, F>
+where
+    I: Iterator,
+    F: FnMut(I::Item, &mut dyn FnMut(&dyn fmt::Display) -> fmt::Result) -> fmt::Result,
+{
+    FormatWith {
+        sep: separator,
+        inner: Cell::new(Some((iter, f))),
+    }
+}
+
+pub fn new_format_default<I>(iter: I, separator: &str) -> Format<'_, I>
+where
+    I: Iterator,
+{
+    Format {
+        sep: separator,
+        inner: Cell::new(Some(iter)),
+    }
+}
+
+impl<I, F> fmt::Display for FormatWith<'_, I, F>
+where
+    I: Iterator,
+    F: FnMut(I::Item, &mut dyn FnMut(&dyn fmt::Display) -> fmt::Result) -> fmt::Result,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let (mut iter, mut format) = match self.inner.take() {
+            Some(t) => t,
+            None => panic!("FormatWith: was already formatted once"),
+        };
+
+        if let Some(fst) = iter.next() {
+            format(fst, &mut |disp: &dyn fmt::Display| disp.fmt(f))?;
+            iter.try_for_each(|elt| {
+                if !self.sep.is_empty() {
+                    f.write_str(self.sep)?;
+                }
+                format(elt, &mut |disp: &dyn fmt::Display| disp.fmt(f))
+            })?;
+        }
+        Ok(())
+    }
+}
+
+impl<I, F> fmt::Debug for FormatWith<'_, I, F>
+where
+    I: Iterator,
+    F: FnMut(I::Item, &mut dyn FnMut(&dyn fmt::Display) -> fmt::Result) -> fmt::Result,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Display::fmt(self, f)
+    }
+}
+
+impl<I> Format<'_, I>
+where
+    I: Iterator,
+{
+    fn format(
+        &self,
+        f: &mut fmt::Formatter,
+        cb: fn(&I::Item, &mut fmt::Formatter) -> fmt::Result,
+    ) -> fmt::Result {
+        let mut iter = match self.inner.take() {
+            Some(t) => t,
+            None => panic!("Format: was already formatted once"),
+        };
+
+        if let Some(fst) = iter.next() {
+            cb(&fst, f)?;
+            iter.try_for_each(|elt| {
+                if !self.sep.is_empty() {
+                    f.write_str(self.sep)?;
+                }
+                cb(&elt, f)
+            })?;
+        }
+        Ok(())
+    }
+}
+
+macro_rules! impl_format {
+    ($($fmt_trait:ident)*) => {
+        $(
+            impl<'a, I> fmt::$fmt_trait for Format<'a, I>
+                where I: Iterator,
+                      I::Item: fmt::$fmt_trait,
+            {
+                fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+                    self.format(f, fmt::$fmt_trait::fmt)
+                }
+            }
+        )*
+    }
+}
+
+impl_format! {Display Debug UpperExp LowerExp UpperHex LowerHex Octal Binary Pointer}
+
+impl<I, F> Clone for FormatWith<'_, I, F>
+where
+    (I, F): Clone,
+{
+    fn clone(&self) -> Self {
+        struct PutBackOnDrop<'r, 'a, I, F> {
+            into: &'r FormatWith<'a, I, F>,
+            inner: Option<(I, F)>,
+        }
+        // This ensures we preserve the state of the original `FormatWith` if `Clone` panics
+        impl<I, F> Drop for PutBackOnDrop<'_, '_, I, F> {
+            fn drop(&mut self) {
+                self.into.inner.set(self.inner.take())
+            }
+        }
+        let pbod = PutBackOnDrop {
+            inner: self.inner.take(),
+            into: self,
+        };
+        Self {
+            inner: Cell::new(pbod.inner.clone()),
+            sep: self.sep,
+        }
+    }
+}
+
+impl<I> Clone for Format<'_, I>
+where
+    I: Clone,
+{
+    fn clone(&self) -> Self {
+        struct PutBackOnDrop<'r, 'a, I> {
+            into: &'r Format<'a, I>,
+            inner: Option<I>,
+        }
+        // This ensures we preserve the state of the original `FormatWith` if `Clone` panics
+        impl<I> Drop for PutBackOnDrop<'_, '_, I> {
+            fn drop(&mut self) {
+                self.into.inner.set(self.inner.take())
+            }
+        }
+        let pbod = PutBackOnDrop {
+            inner: self.inner.take(),
+            into: self,
+        };
+        Self {
+            inner: Cell::new(pbod.inner.clone()),
+            sep: self.sep,
+        }
+    }
+}