Implemented print_align function for #12

Implemented print_align function to replace rust's std fill/align capability.

1 files changed, 57 insertions, 3 deletions

diff --git a/src/utils.rs b/src/utils.rs
index cfb5619..744bf0d 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -2,6 +2,10 @@
 use std::io::{Error, ErrorKind, Write};

 use std::str;

 

+use unicode_width::UnicodeWidthStr;

+

+use super::format::Align;

+

 #[cfg(not(windows))]

 pub static NEWLINE: &'static [u8] = b"\n";

 #[cfg(windows)]

@@ -17,7 +21,7 @@ impl StringWriter {
 	pub fn new() -> StringWriter {

 		return StringWriter{string: String::new()};

 	}

-	

+

 	/// Return a reference to the internally written `String`

 	pub fn as_string(&self) -> &str {

 		return &self.string;

@@ -33,9 +37,59 @@ impl Write for StringWriter {
 		self.string.push_str(string);

 		return Ok(data.len());

 	}

-	

+

 	fn flush(&mut self) -> Result<(), Error> {

 		// Nothing to do here

 		return Ok(());

 	}

-}
\ No newline at end of file
+}

+

+/// Align/fill a string and print it to `out`

+pub fn print_align<T: Write+?Sized>(out: &mut T, align: Align, text: &str, fill: char, size: usize) -> Result<(), Error> {

+	let text_len = UnicodeWidthStr::width(text);

+	let mut nfill = if text_len < size { size - text_len } else { 0 };

+	match align {

+		Align::LEFT => {},

+		Align:: RIGHT => {try!(out.write(&vec![fill as u8; nfill])); nfill = 0;},

+		Align:: CENTER => {try!(out.write(&vec![fill as u8; nfill/2])); nfill -= nfill/2;}

+	}

+	try!(out.write(text.as_bytes()));

+	try!(out.write(&vec![fill as u8; nfill]));

+	return Ok(());

+}

+

+#[cfg(test)]

+mod tests {

+	use super::*;

+	use format::Align;

+	use std::io::Write;

+

+	#[test]

+	fn string_writer() {

+		let mut out = StringWriter::new();

+		out.write("foo".as_bytes()).unwrap();

+		out.write(" ".as_bytes()).unwrap();

+		out.write("".as_bytes()).unwrap();

+		out.write("bar".as_bytes()).unwrap();

+		assert_eq!(out.as_string(), "foo bar");

+	}

+

+	#[test]

+	fn fill_align() {

+		let mut out = StringWriter::new();

+		print_align(&mut out, Align::RIGHT, "foo", '*', 10).unwrap();

+		assert_eq!(out.as_string(), "*******foo");

+

+		let mut out = StringWriter::new();

+		print_align(&mut out, Align::LEFT, "foo", '*', 10).unwrap();

+		assert_eq!(out.as_string(), "foo*******");

+

+		let mut out = StringWriter::new();

+		print_align(&mut out, Align::CENTER, "foo", '*', 10).unwrap();

+		assert_eq!(out.as_string(), "***foo****");

+

+		let mut out = StringWriter::new();

+		print_align(&mut out, Align::CENTER, "foo", '*', 1).unwrap();

+		assert_eq!(out.as_string(), "foo");

+	}

+}