vendor/ansi_term/src/display.rs - third_party/rust-crates - Git at Google

 use std::borrow::Cow;
 use std::fmt;
 use std::io;
 use std::ops::Deref;

 use ansi::RESET;
 use difference::Difference;
 use style::{Style, Colour};
 use write::AnyWrite;


 /// An ANSIGenericString includes a generic string type and a Style to
 /// display that string.  ANSIString and ANSIByteString are aliases for
 /// this type on str and [u8], respectively.
 #[derive(PartialEq, Debug)]
 pub struct ANSIGenericString<'a, S: 'a + ToOwned + ?Sized>
 where <S as ToOwned>::Owned: fmt::Debug {
     style: Style,
     string: Cow<'a, S>,
 }


 /// Cloning an ANSIGenericString will clone its underlying string.
 ///
 /// ### Examples
 ///
 /// ```
 /// use ansi_term::ANSIString;
 ///
 /// let plain_string = ANSIString::from("a plain string");
 /// let clone_string = plain_string.clone();
 /// assert_eq!(clone_string, plain_string);
 /// ```
 impl<'a, S: 'a + ToOwned + ?Sized> Clone for ANSIGenericString<'a, S>
 where <S as ToOwned>::Owned: fmt::Debug {
     fn clone(&self) -> ANSIGenericString<'a, S> {
         ANSIGenericString {
             style: self.style.clone(),
             string: self.string.clone(),
         }
     }
 }

 // You might think that the hand-written Clone impl above is the same as the
 // one that gets generated with #[derive]. But it’s not *quite* the same!
 //
 // `str` is not Clone, and the derived Clone implementation puts a Clone
 // constraint on the S type parameter (generated using --pretty=expanded):
 //
 //                  ↓_________________↓
 //     impl <'a, S: ::std::clone::Clone + 'a + ToOwned + ?Sized> ::std::clone::Clone
 //     for ANSIGenericString<'a, S> where
 //     <S as ToOwned>::Owned: fmt::Debug { ... }
 //
 // This resulted in compile errors when you tried to derive Clone on a type
 // that used it:
 //
 //     #[derive(PartialEq, Debug, Clone, Default)]
 //     pub struct TextCellContents(Vec<ANSIString<'static>>);
 //                                 ^^^^^^^^^^^^^^^^^^^^^^^^^
 //     error[E0277]: the trait `std::clone::Clone` is not implemented for `str`
 //
 // The hand-written impl above can ignore that constraint and still compile.


 /// An ANSI String is a string coupled with the Style to display it
 /// in a terminal.
 ///
 /// Although not technically a string itself, it can be turned into
 /// one with the `to_string` method.
 ///
 /// ### Examples
 ///
 /// ```no_run
 /// use ansi_term::ANSIString;
 /// use ansi_term::Colour::Red;
 ///
 /// let red_string = Red.paint("a red string");
 /// println!("{}", red_string);
 /// ```
 ///
 /// ```
 /// use ansi_term::ANSIString;
 ///
 /// let plain_string = ANSIString::from("a plain string");
 /// assert_eq!(&*plain_string, "a plain string");
 /// ```
 pub type ANSIString<'a> = ANSIGenericString<'a, str>;

 /// An ANSIByteString represents a formatted series of bytes.  Use
 /// ANSIByteString when styling text with an unknown encoding.
 pub type ANSIByteString<'a> = ANSIGenericString<'a, [u8]>;

 impl<'a, I, S: 'a + ToOwned + ?Sized> From<I> for ANSIGenericString<'a, S>
 where I: Into<Cow<'a, S>>,
       <S as ToOwned>::Owned: fmt::Debug {
     fn from(input: I) -> ANSIGenericString<'a, S> {
         ANSIGenericString {
             string: input.into(),
             style:  Style::default(),
         }
     }
 }

 impl<'a, S: 'a + ToOwned + ?Sized> Deref for ANSIGenericString<'a, S>
 where <S as ToOwned>::Owned: fmt::Debug {
     type Target = S;

     fn deref(&self) -> &S {
         self.string.deref()
     }
 }


 /// A set of `ANSIGenericString`s collected together, in order to be
 /// written with a minimum of control characters.
 pub struct ANSIGenericStrings<'a, S: 'a + ToOwned + ?Sized>
     (pub &'a [ANSIGenericString<'a, S>])
     where <S as ToOwned>::Owned: fmt::Debug;

 /// A set of `ANSIString`s collected together, in order to be written with a
 /// minimum of control characters.
 pub type ANSIStrings<'a> = ANSIGenericStrings<'a, str>;

 /// A function to construct an ANSIStrings instance.
 #[allow(non_snake_case)]
 pub fn ANSIStrings<'a>(arg: &'a [ANSIString<'a>]) -> ANSIStrings<'a> {
     ANSIGenericStrings(arg)
 }

 /// A set of `ANSIByteString`s collected together, in order to be
 /// written with a minimum of control characters.
 pub type ANSIByteStrings<'a> = ANSIGenericStrings<'a, [u8]>;

 /// A function to construct an ANSIByteStrings instance.
 #[allow(non_snake_case)]
 pub fn ANSIByteStrings<'a>(arg: &'a [ANSIByteString<'a>]) -> ANSIByteStrings<'a> {
     ANSIGenericStrings(arg)
 }


 // ---- paint functions ----

 impl Style {

     /// Paints the given text with this colour, returning an ANSI string.
     pub fn paint<'a, I, S: 'a + ToOwned + ?Sized>(self, input: I) -> ANSIGenericString<'a, S>
     where I: Into<Cow<'a, S>>,
           <S as ToOwned>::Owned: fmt::Debug {
         ANSIGenericString {
             string: input.into(),
             style:  self,
         }
     }
 }


 impl Colour {

     /// Paints the given text with this colour, returning an ANSI string.
     /// This is a short-cut so you don’t have to use `Blue.normal()` just
     /// to get blue text.
     ///
     /// ```
     /// use ansi_term::Colour::Blue;
     /// println!("{}", Blue.paint("da ba dee"));
     /// ```
     pub fn paint<'a, I, S: 'a + ToOwned + ?Sized>(self, input: I) -> ANSIGenericString<'a, S>
     where I: Into<Cow<'a, S>>,
           <S as ToOwned>::Owned: fmt::Debug {
         ANSIGenericString {
             string: input.into(),
             style:  self.normal(),
         }
     }
 }


 // ---- writers for individual ANSI strings ----

 impl<'a> fmt::Display for ANSIString<'a> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let w: &mut fmt::Write = f;
         self.write_to_any(w)
     }
 }

 impl<'a> ANSIByteString<'a> {
     /// Write an ANSIByteString to an io::Write.  This writes the escape
     /// sequences for the associated Style around the bytes.
     pub fn write_to<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
         let w: &mut io::Write = w;
         self.write_to_any(w)
     }
 }

 impl<'a, S: 'a + ToOwned + ?Sized> ANSIGenericString<'a, S>
 where <S as ToOwned>::Owned: fmt::Debug, &'a S: AsRef<[u8]> {
     fn write_to_any<W: AnyWrite<wstr=S> + ?Sized>(&self, w: &mut W) -> Result<(), W::Error> {
         write!(w, "{}", self.style.prefix())?;
         w.write_str(self.string.as_ref())?;
         write!(w, "{}", self.style.suffix())
     }
 }


 // ---- writers for combined ANSI strings ----

 impl<'a> fmt::Display for ANSIStrings<'a> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let f: &mut fmt::Write = f;
         self.write_to_any(f)
     }
 }

 impl<'a> ANSIByteStrings<'a> {
     /// Write ANSIByteStrings to an io::Write.  This writes the minimal
     /// escape sequences for the associated Styles around each set of
     /// bytes.
     pub fn write_to<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
         let w: &mut io::Write = w;
         self.write_to_any(w)
     }
 }

 impl<'a, S: 'a + ToOwned + ?Sized> ANSIGenericStrings<'a, S>
 where <S as ToOwned>::Owned: fmt::Debug, &'a S: AsRef<[u8]> {
     fn write_to_any<W: AnyWrite<wstr=S> + ?Sized>(&self, w: &mut W) -> Result<(), W::Error> {
         use self::Difference::*;

         let first = match self.0.first() {
             None => return Ok(()),
             Some(f) => f,
         };

         write!(w, "{}", first.style.prefix())?;
         w.write_str(first.string.as_ref())?;

         for window in self.0.windows(2) {
             match Difference::between(&window[0].style, &window[1].style) {
                 ExtraStyles(style) => write!(w, "{}", style.prefix())?,
                 Reset              => write!(w, "{}{}", RESET, window[1].style.prefix())?,
                 NoDifference       => {/* Do nothing! */},
             }

             w.write_str(&window[1].string)?;
         }

         // Write the final reset string after all of the ANSIStrings have been
         // written, *except* if the last one has no styles, because it would
         // have already been written by this point.
         if let Some(last) = self.0.last() {
             if !last.style.is_plain() {
                 write!(w, "{}", RESET)?;
             }
         }

         Ok(())
     }
 }


 // ---- tests ----

 #[cfg(test)]
 mod tests {
     pub use super::super::ANSIStrings;
     pub use style::Style;
     pub use style::Colour::*;

     #[test]
     fn no_control_codes_for_plain() {
         let one = Style::default().paint("one");
         let two = Style::default().paint("two");
         let output = format!("{}", ANSIStrings( &[ one, two ] ));
         assert_eq!(&*output, "onetwo");
     }
 }
	use std::borrow::Cow;
	use std::fmt;
	use std::io;
	use std::ops::Deref;

	use ansi::RESET;
	use difference::Difference;
	use style::{Style, Colour};
	use write::AnyWrite;


	/// An ANSIGenericString includes a generic string type and a Style to
	/// display that string. ANSIString and ANSIByteString are aliases for
	/// this type on str and [u8], respectively.
	#[derive(PartialEq, Debug)]
	pub struct ANSIGenericString<'a, S: 'a + ToOwned + ?Sized>
	where <S as ToOwned>::Owned: fmt::Debug {
	style: Style,
	string: Cow<'a, S>,
	}


	/// Cloning an ANSIGenericString will clone its underlying string.
	///
	/// ### Examples
	///
	/// ```
	/// use ansi_term::ANSIString;
	///
	/// let plain_string = ANSIString::from("a plain string");
	/// let clone_string = plain_string.clone();
	/// assert_eq!(clone_string, plain_string);
	/// ```
	impl<'a, S: 'a + ToOwned + ?Sized> Clone for ANSIGenericString<'a, S>
	where <S as ToOwned>::Owned: fmt::Debug {
	fn clone(&self) -> ANSIGenericString<'a, S> {
	ANSIGenericString {
	style: self.style.clone(),
	string: self.string.clone(),
	}
	}
	}

	// You might think that the hand-written Clone impl above is the same as the
	// one that gets generated with #[derive]. But it’s not quite the same!
	//
	// `str` is not Clone, and the derived Clone implementation puts a Clone
	// constraint on the S type parameter (generated using --pretty=expanded):
	//
	// ↓_________________↓
	// impl <'a, S: ::std::clone::Clone + 'a + ToOwned + ?Sized> ::std::clone::Clone
	// for ANSIGenericString<'a, S> where
	// <S as ToOwned>::Owned: fmt::Debug { ... }
	//
	// This resulted in compile errors when you tried to derive Clone on a type
	// that used it:
	//
	// #[derive(PartialEq, Debug, Clone, Default)]
	// pub struct TextCellContents(Vec<ANSIString<'static>>);
	// ^^^^^^^^^^^^^^^^^^^^^^^^^
	// error[E0277]: the trait `std::clone::Clone` is not implemented for `str`
	//
	// The hand-written impl above can ignore that constraint and still compile.



	/// An ANSI String is a string coupled with the Style to display it
	/// in a terminal.
	///
	/// Although not technically a string itself, it can be turned into
	/// one with the `to_string` method.
	///
	/// ### Examples
	///
	/// ```no_run
	/// use ansi_term::ANSIString;
	/// use ansi_term::Colour::Red;
	///
	/// let red_string = Red.paint("a red string");
	/// println!("{}", red_string);
	/// ```
	///
	/// ```
	/// use ansi_term::ANSIString;
	///
	/// let plain_string = ANSIString::from("a plain string");
	/// assert_eq!(&*plain_string, "a plain string");
	/// ```
	pub type ANSIString<'a> = ANSIGenericString<'a, str>;

	/// An ANSIByteString represents a formatted series of bytes. Use
	/// ANSIByteString when styling text with an unknown encoding.
	pub type ANSIByteString<'a> = ANSIGenericString<'a, [u8]>;

	impl<'a, I, S: 'a + ToOwned + ?Sized> From<I> for ANSIGenericString<'a, S>
	where I: Into<Cow<'a, S>>,
	<S as ToOwned>::Owned: fmt::Debug {
	fn from(input: I) -> ANSIGenericString<'a, S> {
	ANSIGenericString {
	string: input.into(),
	style: Style::default(),
	}
	}
	}

	impl<'a, S: 'a + ToOwned + ?Sized> Deref for ANSIGenericString<'a, S>
	where <S as ToOwned>::Owned: fmt::Debug {
	type Target = S;

	fn deref(&self) -> &S {
	self.string.deref()
	}
	}


	/// A set of `ANSIGenericString`s collected together, in order to be
	/// written with a minimum of control characters.
	pub struct ANSIGenericStrings<'a, S: 'a + ToOwned + ?Sized>
	(pub &'a [ANSIGenericString<'a, S>])
	where <S as ToOwned>::Owned: fmt::Debug;

	/// A set of `ANSIString`s collected together, in order to be written with a
	/// minimum of control characters.
	pub type ANSIStrings<'a> = ANSIGenericStrings<'a, str>;

	/// A function to construct an ANSIStrings instance.
	#[allow(non_snake_case)]
	pub fn ANSIStrings<'a>(arg: &'a [ANSIString<'a>]) -> ANSIStrings<'a> {
	ANSIGenericStrings(arg)
	}

	/// A set of `ANSIByteString`s collected together, in order to be
	/// written with a minimum of control characters.
	pub type ANSIByteStrings<'a> = ANSIGenericStrings<'a, [u8]>;

	/// A function to construct an ANSIByteStrings instance.
	#[allow(non_snake_case)]
	pub fn ANSIByteStrings<'a>(arg: &'a [ANSIByteString<'a>]) -> ANSIByteStrings<'a> {
	ANSIGenericStrings(arg)
	}


	// ---- paint functions ----

	impl Style {

	/// Paints the given text with this colour, returning an ANSI string.
	pub fn paint<'a, I, S: 'a + ToOwned + ?Sized>(self, input: I) -> ANSIGenericString<'a, S>
	where I: Into<Cow<'a, S>>,
	<S as ToOwned>::Owned: fmt::Debug {
	ANSIGenericString {
	string: input.into(),
	style: self,
	}
	}
	}


	impl Colour {

	/// Paints the given text with this colour, returning an ANSI string.
	/// This is a short-cut so you don’t have to use `Blue.normal()` just
	/// to get blue text.
	///
	/// ```
	/// use ansi_term::Colour::Blue;
	/// println!("{}", Blue.paint("da ba dee"));
	/// ```
	pub fn paint<'a, I, S: 'a + ToOwned + ?Sized>(self, input: I) -> ANSIGenericString<'a, S>
	where I: Into<Cow<'a, S>>,
	<S as ToOwned>::Owned: fmt::Debug {
	ANSIGenericString {
	string: input.into(),
	style: self.normal(),
	}
	}
	}


	// ---- writers for individual ANSI strings ----

	impl<'a> fmt::Display for ANSIString<'a> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
	let w: &mut fmt::Write = f;
	self.write_to_any(w)
	}
	}

	impl<'a> ANSIByteString<'a> {
	/// Write an ANSIByteString to an io::Write. This writes the escape
	/// sequences for the associated Style around the bytes.
	pub fn write_to<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
	let w: &mut io::Write = w;
	self.write_to_any(w)
	}
	}

	impl<'a, S: 'a + ToOwned + ?Sized> ANSIGenericString<'a, S>
	where <S as ToOwned>::Owned: fmt::Debug, &'a S: AsRef<[u8]> {
	fn write_to_any<W: AnyWrite<wstr=S> + ?Sized>(&self, w: &mut W) -> Result<(), W::Error> {
	write!(w, "{}", self.style.prefix())?;
	w.write_str(self.string.as_ref())?;
	write!(w, "{}", self.style.suffix())
	}
	}


	// ---- writers for combined ANSI strings ----

	impl<'a> fmt::Display for ANSIStrings<'a> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
	let f: &mut fmt::Write = f;
	self.write_to_any(f)
	}
	}

	impl<'a> ANSIByteStrings<'a> {
	/// Write ANSIByteStrings to an io::Write. This writes the minimal
	/// escape sequences for the associated Styles around each set of
	/// bytes.
	pub fn write_to<W: io::Write>(&self, w: &mut W) -> io::Result<()> {
	let w: &mut io::Write = w;
	self.write_to_any(w)
	}
	}

	impl<'a, S: 'a + ToOwned + ?Sized> ANSIGenericStrings<'a, S>
	where <S as ToOwned>::Owned: fmt::Debug, &'a S: AsRef<[u8]> {
	fn write_to_any<W: AnyWrite<wstr=S> + ?Sized>(&self, w: &mut W) -> Result<(), W::Error> {
	use self::Difference::*;

	let first = match self.0.first() {
	None => return Ok(()),
	Some(f) => f,
	};

	write!(w, "{}", first.style.prefix())?;
	w.write_str(first.string.as_ref())?;

	for window in self.0.windows(2) {
	match Difference::between(&window[0].style, &window[1].style) {
	ExtraStyles(style) => write!(w, "{}", style.prefix())?,
	Reset => write!(w, "{}{}", RESET, window[1].style.prefix())?,
	NoDifference => {/* Do nothing! */},
	}

	w.write_str(&window[1].string)?;
	}

	// Write the final reset string after all of the ANSIStrings have been
	// written, except if the last one has no styles, because it would
	// have already been written by this point.
	if let Some(last) = self.0.last() {
	if !last.style.is_plain() {
	write!(w, "{}", RESET)?;
	}
	}

	Ok(())
	}
	}


	// ---- tests ----

	#[cfg(test)]
	mod tests {
	pub use super::super::ANSIStrings;
	pub use style::Style;
	pub use style::Colour::*;

	#[test]
	fn no_control_codes_for_plain() {
	let one = Style::default().paint("one");
	let two = Style::default().paint("two");
	let output = format!("{}", ANSIStrings( &[ one, two ] ));
	assert_eq!(&*output, "onetwo");
	}
	}