Closer to parsing the json string

This commit is contained in:
Timothy Warren 2020-02-10 14:59:28 -05:00
parent d87c2cf165
commit 45e888291c

View File

@ -254,42 +254,25 @@ impl JSON {
let max = self.chars.len() - 1;
let mut n = start;
// Minus sign
if self.chars[n] == '-' && n < max {
n += 1;
}
if self.chars[n] == '0' && n < max {
// Integer Part
while self.chars[n].is_ascii_digit() && n < max {
n += 1;
} else if self.chars[n] >= '1' && self.chars[n] <= '9' && n < max {
n += 1;
loop {
if n + 1 > max {
break;
}
if self.chars[n + 1].is_ascii_digit() {
n += 1;
} else {
break;
}
}
}
// Decimal Part
if self.chars[n] == '.' && n < max {
n += 1;
loop {
if n + 1 > max {
break;
}
if self.chars[n + 1].is_ascii_digit() {
n += 1;
} else {
break;
}
while self.chars[n].is_ascii_digit() && n < max {
n += 1;
}
}
// Scientific notation part
if self.chars[n] == 'e' || self.chars[n] == 'E' && n < max {
n += 1;
@ -297,33 +280,30 @@ impl JSON {
n += 1;
}
// expect digit
loop {
if n + 1 > max {
break;
}
if self.chars[n + 1].is_ascii_digit() {
n += 1;
} else {
break;
}
while self.chars[n].is_ascii_digit() && n < max {
n += 1;
}
}
// If there are numeric digits attempt to parse the digits as a number
if n > start {
let end = if n < self.chars.len() {
let mut end = if n < self.chars.len() {
n
} else {
max
};
// Hack to remove non-number characters
if !self.chars[end].is_ascii_digit() {
end -= 1;
}
let str = String::from_iter(&self.chars[start..=end]);
match str.parse::<f64>() {
Ok(n) => {
self.increment(str.len() - 1);
return Ok(Some(JSONValue::Number(n)))
Ok(number) => {
self.increment(str.len());
return Ok(Some(JSONValue::Number(number)))
},
Err(e) => Err(ParseError::ExpectedDigit(format!("'{}', {:#?}", str, e))),
}
@ -373,11 +353,17 @@ impl JSON {
return Err(ParseError::ExpectedToken(msg));
}
self.increment(1);
self.skip();
Ok(())
}
/// Skip a character
fn skip(&mut self) {
self.increment(1);
}
/// Do a checked increment of the internal pointer index
fn increment(&mut self, amount: usize) {
let current = self.i;
if current + amount >= self.chars.len() {
@ -469,6 +455,15 @@ mod tests {
);
}
#[test]
fn parse_object() {
let mut parser = JSON::new(r#"{"foo": "bar"}"#);
let result = JSON::parse_object(&mut parser);
let mut hash_map: HashMap<String, JSONValue> = HashMap::new();
hash_map.insert(String::from("foo"), JSONValue::String(String::from("bar")));
assert_eq!(result, Ok(Some(JSONValue::Object(hash_map))));
}
#[test]
fn parse_json_types() {
// Boolean / Null
@ -486,6 +481,10 @@ mod tests {
// String
let res = JSON::parse(r#""/^$/""#);
assert_eq!(res, Ok(JSONValue::String(String::from("/^$/"))), "Failed to parse string");
// Number array
let res = JSON::parse("[1, 2, 3]");
assert_eq!(res, Ok(JSONValue::Array(vec![JSONValue::Number(1f64), JSONValue::Number(2f64), JSONValue::Number(3f64)])));
}
#[test]