Merge branch 'develop' into 0.14

src/proto/colors.rs

@@ -0,0 +1,188 @@
+//! An extension trait that provides the ability to strip IRC colors from a string
+use std::borrow::Cow;
+
+enum ParserState {
+    Text,
+    ColorCode,
+    Foreground1(char),
+    Foreground2,
+    Comma,
+    Background1(char),
+}
+struct Parser {
+    state: ParserState,
+}
+
+/// An extension trait giving strings a function to strip IRC colors
+pub trait FormattedStringExt<'a> {
+
+    /// Returns true if the string contains color, bold, underline or italics
+    fn is_formatted(&self) -> bool;
+
+    /// Returns the string with all color, bold, underline and italics stripped
+    fn strip_formatting(self) -> Cow<'a, str>;
+
+}
+
+const FORMAT_CHARACTERS: &[char] = &[
+    '\x02', // bold
+    '\x1F', // underline
+    '\x16', // reverse
+    '\x0F', // normal
+    '\x03', // color
+];
+
+impl<'a> FormattedStringExt<'a> for &'a str {
+    fn is_formatted(&self) -> bool {
+        self.contains(FORMAT_CHARACTERS)
+    }
+
+    fn strip_formatting(self) -> Cow<'a, str> {
+        if !self.is_formatted() {
+            return Cow::Borrowed(self);
+        }
+        let mut s = String::from(self);
+        strip_formatting(&mut s);
+        Cow::Owned(s)
+    }
+}
+
+fn strip_formatting(buf: &mut String) {
+    let mut parser = Parser::new();
+    buf.retain(|cur| parser.next(cur));
+}
+
+impl Parser {
+    fn new() -> Self {
+        Parser  {
+            state: ParserState::Text,
+        }
+    }
+
+    fn next(&mut self, cur: char) -> bool {
+        use self::ParserState::*;
+        match self.state {
+            Text | Foreground1(_) | Foreground2 if cur == '\x03' => {
+                self.state = ColorCode;
+                false
+            }
+            Text => {
+                !FORMAT_CHARACTERS.contains(&cur)
+            }
+            ColorCode if cur.is_digit(10) => {
+                self.state = Foreground1(cur);
+                false
+            }
+            Foreground1('1') if cur.is_digit(6) => {
+                // can only consume another digit if previous char was 1.
+                self.state = Foreground2;
+                false
+            }
+            Foreground1(_) if cur.is_digit(6) => {
+                self.state = Text;
+                true
+            }
+            Foreground1(_) if cur == ',' => {
+                self.state = Comma;
+                false
+            }
+            Foreground2 if cur == ',' => {
+                self.state = Comma;
+                false
+            }
+            Comma if (cur.is_digit(10)) => {
+                self.state = Background1(cur);
+                false
+            }
+            Background1(prev) if cur.is_digit(6) => {
+                // can only consume another digit if previous char was 1.
+                self.state = Text;
+                prev != '1'
+            }
+            _ => {
+                self.state = Text;
+                true
+            }
+        }
+    }
+}
+
+impl FormattedStringExt<'static> for String {
+    fn is_formatted(&self) -> bool {
+        self.as_str().is_formatted()
+    }
+    fn strip_formatting(mut self) -> Cow<'static, str> {
+        if !self.is_formatted() {
+            return Cow::Owned(self);
+        }
+        strip_formatting(&mut self);
+        Cow::Owned(self)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use std::borrow::Cow;
+    use proto::colors::FormattedStringExt;
+
+    macro_rules! test_formatted_string_ext {
+        { $( $name:ident ( $($line:tt)* ), )* } => {
+            $(
+            mod $name {
+                use super::*;
+                test_formatted_string_ext!(@ $($line)*);
+            }
+            )*
+        };
+        (@ $text:expr, should stripped into $expected:expr) => {
+            #[test]
+            fn test_formatted() {
+                assert!($text.is_formatted());
+            }
+            #[test]
+            fn test_strip() {
+                assert_eq!($text.strip_formatting(), $expected);
+            }
+        };
+        (@ $text:expr, is not formatted) => {
+            #[test]
+            fn test_formatted() {
+                assert!(!$text.is_formatted());
+            }
+            #[test]
+            fn test_strip() {
+                assert_eq!($text.strip_formatting(), $text);
+            }
+        }
+    }
+
+    test_formatted_string_ext! {
+        blank("", is not formatted),
+        blank2("    ", is not formatted),
+        blank3("\t\r\n", is not formatted),
+        bold("l\x02ol", should stripped into "lol"),
+        bold_from_string(String::from("l\x02ol"), should stripped into "lol"),
+        bold_hangul("우왕\x02굳", should stripped into "우왕굳"),
+        fg_color("l\x033ol", should stripped into "lol"),
+        fg_color2("l\x0312ol", should stripped into "lol"),
+        fg_bg_11("l\x031,2ol", should stripped into "lol"),
+        fg_bg_21("l\x0312,3ol", should stripped into "lol"),
+        fg_bg_12("l\x031,12ol", should stripped into "lol"),
+        fg_bg_22("l\x0312,13ol", should stripped into "lol"),
+        string_with_multiple_colors("hoo\x034r\x033a\x0312y", should stripped into "hooray"),
+        string_with_digit_after_color("\x0344\x0355\x0366", should stripped into "456"),
+        string_with_multiple_2digit_colors("hoo\x0310r\x0311a\x0312y", should stripped into "hooray"),
+        string_with_digit_after_2digit_color("\x031212\x031111\x031010", should stripped into "121110"),
+        thinking("🤔...", is not formatted),
+        unformatted("a plain text", is not formatted),
+    }
+
+    #[test]
+    fn test_strip_no_allocation_for_unformatted_text() {
+        if let Cow::Borrowed(formatted) = "plain text".strip_formatting() {
+            assert_eq!(formatted, "plain text");
+        } else {
+            panic!("allocation detected");
+        }
+    }
+}