diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/ser.rs | 146 |
1 files changed, 91 insertions, 55 deletions
@@ -458,14 +458,21 @@ impl<'a> Serializer<'a> { } fn emit_str(&mut self, value: &str, is_key: bool) -> Result<(), Error> { - /// Use ''' or ' #[derive(PartialEq)] - enum Multi { - False, - True, - Single, + enum Type { + NewlineTripple, + OnelineTripple, + OnelineSingle, } - fn do_pretty(value: &str) -> Option<(Multi, String)> { + + enum Repr { + /// represent as a literal string (using '') + Literal(String, Type), + /// represent the std way (using "") + Std(Type), + } + + fn do_pretty(value: &str) -> Repr { // For doing pretty prints we store in a new String // because there are too many cases where pretty cannot // work. We need to determine: @@ -476,77 +483,106 @@ impl<'a> Serializer<'a> { // Doing it any other way would require multiple passes // to determine if a pretty string works or not. let mut out = String::with_capacity(value.len() * 2); - let mut multi = Multi::False; + let mut ty = Type::OnelineSingle; // found consecutive single quotes let mut max_found_singles = 0; let mut found_singles = 0; + let mut can_be_pretty = true; for ch in value.chars() { - if ch == '\'' { - found_singles += 1; - if found_singles >= 3 { - return None; + if can_be_pretty { + if ch == '\'' { + found_singles += 1; + if found_singles >= 3 { + can_be_pretty = false; + } + } else { + if found_singles > max_found_singles { + max_found_singles = found_singles; + } + found_singles = 0 + } + match ch { + '\t' => {}, + '\n' => ty = Type::NewlineTripple, + // note that the following are invalid: \b \f \r + c if c < '\u{1f}' => can_be_pretty = false, // Invalid control character + _ => {} } + out.push(ch); } else { - if found_singles > max_found_singles { - max_found_singles = found_singles; + // the string cannot be represented as pretty, + // still check if it should be multiline + if ch == '\n' { + ty = Type::NewlineTripple; } - found_singles = 0 } - match ch { - '\t' => {}, - '\n' => multi = Multi::True, - // note that the following are invalid: \b \f \r - c if c < '\u{1f}' => return None, // Invalid control character - _ => {} - } - out.push(ch); + } + if !can_be_pretty { + debug_assert!(ty != Type::OnelineTripple); + return Repr::Std(ty); } if found_singles > max_found_singles { max_found_singles = found_singles; } debug_assert!(max_found_singles < 3); - if multi == Multi::False && max_found_singles >= 1 { + if ty == Type::OnelineSingle && max_found_singles >= 1 { // no newlines, but must use ''' because it has ' in it - multi = Multi::Single; + ty = Type::OnelineTripple; } - Some((multi, out)) + Repr::Literal(out, ty) } - let pretty = if !is_key && self.settings.pretty_string { + let repr = if !is_key && self.settings.pretty_string { do_pretty(value) } else { - None + Repr::Std(Type::OnelineSingle) }; - if let Some((multi, s)) = pretty { - // A pretty string - match multi { - Multi::True => self.dst.push_str("'''\n"), - Multi::Single => self.dst.push_str("'''"), - Multi::False => self.dst.push('\''), - } - self.dst.push_str(&s); - match multi { - Multi::False => self.dst.push('\''), - _ => self.dst.push_str("'''"), - } - } else { - // Not a pretty string - drop(write!(self.dst, "\"")); - for ch in value.chars() { - match ch { - '\u{8}' => self.dst.push_str("\\b"), - '\u{9}' => self.dst.push_str("\\t"), - '\u{a}' => self.dst.push_str("\\n"), - '\u{c}' => self.dst.push_str("\\f"), - '\u{d}' => self.dst.push_str("\\r"), - '\u{22}' => self.dst.push_str("\\\""), - '\u{5c}' => self.dst.push_str("\\\\"), - c if c < '\u{1f}' => drop(write!(self.dst, "\\u{:04X}", ch as u32)), - ch => self.dst.push(ch), + match repr { + Repr::Literal(literal, ty) => { + // A pretty string + match ty { + Type::NewlineTripple => self.dst.push_str("'''\n"), + Type::OnelineTripple => self.dst.push_str("'''"), + Type::OnelineSingle => self.dst.push('\''), } - } - self.dst.push_str("\""); + self.dst.push_str(&literal); + match ty { + Type::OnelineSingle => self.dst.push('\''), + _ => self.dst.push_str("'''"), + } + }, + Repr::Std(ty) => { + match ty { + Type::NewlineTripple => self.dst.push_str("\"\"\"\n"), + Type::OnelineSingle => self.dst.push('"'), + _ => unreachable!(), + } + for ch in value.chars() { + match ch { + '\u{8}' => self.dst.push_str("\\b"), + '\u{9}' => self.dst.push_str("\\t"), + '\u{a}' => { + match ty { + Type::NewlineTripple => self.dst.push('\n'), + Type::OnelineSingle => self.dst.push_str("\\n"), + _ => unreachable!(), + } + }, + '\u{c}' => self.dst.push_str("\\f"), + '\u{d}' => self.dst.push_str("\\r"), + '\u{22}' => self.dst.push_str("\\\""), + '\u{5c}' => self.dst.push_str("\\\\"), + c if c < '\u{1f}' => drop(write!(self.dst, "\\u{:04X}", ch as u32)), + ch => self.dst.push(ch), + } + } + match ty { + Type::NewlineTripple => self.dst.push_str("\"\"\""), + Type::OnelineSingle => self.dst.push('"'), + _ => unreachable!(), + } + }, } Ok(()) } |