From a29c1eeef04eed525d7fe48b8e06ae31c0a60575 Mon Sep 17 00:00:00 2001 From: Garrett Berg Date: Thu, 27 Jul 2017 22:44:58 -0600 Subject: make single lines also pretty --- src/ser.rs | 146 ++++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 102 insertions(+), 44 deletions(-) (limited to 'src/ser.rs') diff --git a/src/ser.rs b/src/ser.rs index febe429..516b25f 100644 --- a/src/ser.rs +++ b/src/ser.rs @@ -201,6 +201,7 @@ enum State<'a> { parent: &'a State<'a>, first: &'a Cell, type_: &'a Cell>, + len: Option, }, End, } @@ -210,6 +211,7 @@ pub struct SerializeSeq<'a: 'b, 'b> { ser: &'b mut Serializer<'a>, first: Cell, type_: Cell>, + len: Option, } #[doc(hidden)] @@ -377,12 +379,12 @@ impl<'a> Serializer<'a> { fn _emit_key(&mut self, state: &State) -> Result<(), Error> { match *state { State::End => Ok(()), - State::Array { parent, first, type_ } => { + State::Array { parent, first, type_, len } => { assert!(type_.get().is_some()); if first.get() { self._emit_key(parent)?; } - self.emit_array(first) + self.emit_array(first, len) } State::Table { parent, first, table_emitted, key } => { if table_emitted.get() { @@ -399,9 +401,16 @@ impl<'a> Serializer<'a> { } } - fn emit_array(&mut self, first: &Cell) -> Result<(), Error> { - match self.settings.array { - Some(ref a) => { + fn emit_array(&mut self, first: &Cell, len: Option) -> Result<(), Error> { + match (len, &self.settings.array) { + (Some(0...1), _) | (_, &None) => { + if first.get() { + self.dst.push_str("[") + } else { + self.dst.push_str(", ") + } + }, + (_, &Some(ref a)) => { if first.get() { self.dst.push_str("[\n") } else { @@ -411,13 +420,6 @@ impl<'a> Serializer<'a> { self.dst.push_str(" "); } }, - None => { - if first.get() { - self.dst.push_str("[") - } else { - self.dst.push_str(", ") - } - }, } Ok(()) } @@ -456,41 +458,95 @@ impl<'a> Serializer<'a> { } fn emit_str(&mut self, value: &str, is_key: bool) -> Result<(), Error> { - let do_pretty = if !is_key && self.settings.pretty_string { - // do pretty only if the block contains at least one newline - value.contains('\n') - // but not if it contains any of these, as they are not - // representable - && !value.contains("'''") + /// Use ''' or ' + #[derive(PartialEq)] + enum Multi { + False, + True, + Single, + } + fn do_pretty(value: &str) -> Option<(Multi, String)> { + // For doing pretty prints we store in a new String + // because there are too many cases where pretty cannot + // work. We need to determine: + // - if we are a "multi-line" pretty (if there are \n) + // - if ['''] appears if multi or ['] if single + // - if there are any invalid control characters + // + // 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; + // found consecutive single quotes + let mut max_found_singles = 0; + let mut found_singles = 0; + + for ch in value.chars() { + if ch == '\'' { + found_singles += 1; + if found_singles >= 3 { + return None; + } + } else { + if found_singles > max_found_singles { + max_found_singles = found_singles; + } + 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 found_singles > max_found_singles { + max_found_singles = found_singles; + } + debug_assert!(max_found_singles < 3); + if multi == Multi::False && max_found_singles >= 1 { + // no newlines, but must use ''' because it has ' in it + multi = Multi::Single; + } + Some((multi, out)) + } + + let pretty = if !is_key && self.settings.pretty_string { + do_pretty(value) } else { - false + None }; - if do_pretty { - drop(write!(self.dst, "'''\n")); + 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, "\"")); - } - if do_pretty { - drop(write!(self.dst, "{}", value)); - } else { for ch in value.chars() { match ch { - '\u{8}' => drop(write!(self.dst, "\\b")), - '\u{9}' => drop(write!(self.dst, "\\t")), - '\u{a}' => drop(write!(self.dst, "\\n")), - '\u{c}' => drop(write!(self.dst, "\\f")), - '\u{d}' => drop(write!(self.dst, "\\r")), - '\u{22}' => drop(write!(self.dst, "\\\"")), - '\u{5c}' => drop(write!(self.dst, "\\\\")), + '\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 => drop(write!(self.dst, "{}", ch)), + ch => self.dst.push(ch), } } - } - if do_pretty { - drop(write!(self.dst, "'''")); - } else { - drop(write!(self.dst, "\"")); + self.dst.push_str("\""); } Ok(()) } @@ -703,13 +759,14 @@ impl<'a, 'b> ser::Serializer for &'b mut Serializer<'a> { Err(Error::UnsupportedType) } - fn serialize_seq(mut self, _len: Option) + fn serialize_seq(mut self, len: Option) -> Result { self.array_type("array")?; Ok(SerializeSeq { ser: self, first: Cell::new(true), type_: Cell::new(None), + len: len, }) } @@ -782,6 +839,7 @@ impl<'a, 'b> ser::SerializeSeq for SerializeSeq<'a, 'b> { parent: &self.ser.state, first: &self.first, type_: &self.type_, + len: self.len, }, settings: self.ser.settings.clone(), })?; @@ -793,16 +851,16 @@ impl<'a, 'b> ser::SerializeSeq for SerializeSeq<'a, 'b> { match self.type_.get() { Some("table") => return Ok(()), Some(_) => { - match self.ser.settings.array { - Some(ref a) => { + match (self.len, &self.ser.settings.array) { + (Some(0...1), _) | (_, &None) => { + self.ser.dst.push_str("]"); + }, + (_, &Some(ref a)) => { if a.trailing_comma { self.ser.dst.push_str(","); } self.ser.dst.push_str("\n]"); }, - None => { - self.ser.dst.push_str("]"); - } } } None => { -- cgit v1.2.3