improve handling of invalid literals when a lone decimal terminates a document

Author: spyoungtech

src/de.rs

@@ -70,7 +70,7 @@ impl<'de, 'a> Deserializer<'de> for JSONValueDeserializer<'a> {
  visitor.visit_u64(u)
  } else {
  // fallback: treat as a string or produce an error
- Err(de::Error::custom(format!("Invalid integer {}", s)))
+ Err(de::Error::custom(format!("Invalid integer literal: {}", s)))
  }
  }
  }

src/tokenize.rs

@@ -224,10 +224,22 @@ impl <'input> Tokenizer<'input> {
 
  fn process_number(&mut self) -> Result<TokenSpan, TokenizationError>{
  let (start_idx, start_char) = self.lookahead.expect("Unexpected end of input, was expecting numeric char");
+ let mut last_index = start_idx;
+ let mut decimal_seen: bool = false;
+ let mut exponent_seen: bool = false;
+ let mut unary_seen: bool = false;
+ if start_char == '.' {
+ decimal_seen = true
+ }
 
  let maybe_second_char = self.chars.peek();
  match maybe_second_char {
- None => return Ok((start_idx, TokType::Integer, start_idx + 1)),
+ None => {
+ if decimal_seen {
+ return Err(self.make_error("Lone decimal is an invalid literal".to_string(), start_idx))
+ }
+ return Ok((start_idx, TokType::Integer, start_idx + 1))
+ },
  Some((_second_idx, second_char)) if start_char == '0' => {
  match second_char {
  'x' | 'X' => {return self.process_hexadecimal()}
@@ -240,15 +252,6 @@ impl <'input> Tokenizer<'input> {
  _ => {}
  }
 
- let mut last_index = start_idx;
- let mut decimal_seen: bool = false;
- let mut exponent_seen: bool = false;
- let mut unary_seen: bool = false;
- match start_char {
- '.' => {decimal_seen = true}
- '+' | '-' => {unary_seen = true}
- _ => {}
- }
  loop {
  match self.chars.peek() {
  None => {