reifydb_sql/
token.rs

1// SPDX-License-Identifier: Apache-2.0
2// Copyright (c) 2025 ReifyDB
3
4use crate::Error;
5
6#[derive(Debug, Clone, PartialEq)]
7pub enum Token {
8	// Keywords
9	Keyword(Keyword),
10	// Identifiers
11	Ident(String),
12	// Literals
13	Integer(i64),
14	Float(f64),
15	StringLit(String),
16	// Operators & punctuation
17	Asterisk,   // *
18	Comma,      // ,
19	Dot,        // .
20	Semicolon,  // ;
21	OpenParen,  // (
22	CloseParen, // )
23	Plus,       // +
24	Minus,      // -
25	Slash,      // /
26	Percent,    // %
27	Eq,         // =
28	NotEq,      // <> or !=
29	Lt,         // <
30	Gt,         // >
31	LtEq,       // <=
32	GtEq,       // >=
33	Concat,     // ||
34}
35
36#[derive(Debug, Clone, PartialEq)]
37pub enum Keyword {
38	Select,
39	From,
40	Where,
41	And,
42	Or,
43	Not,
44	As,
45	Order,
46	By,
47	Asc,
48	Desc,
49	Limit,
50	Offset,
51	Group,
52	Having,
53	Distinct,
54	Insert,
55	Into,
56	Values,
57	Update,
58	Set,
59	Delete,
60	Create,
61	Table,
62	Join,
63	Inner,
64	Left,
65	Right,
66	On,
67	Null,
68	True,
69	False,
70	Is,
71	In,
72	Between,
73	Cast,
74	Count,
75	Sum,
76	Avg,
77	Min,
78	Max,
79	// SQL types
80	Int,
81	Int2,
82	Int4,
83	Int8,
84	Smallint,
85	Integer,
86	Bigint,
87	Float4,
88	Float8,
89	Real,
90	Double,
91	Precision,
92	Boolean,
93	Bool,
94	Varchar,
95	Text,
96	Char,
97	Utf8,
98	Blob,
99	Primary,
100	Key,
101	With,
102	Recursive,
103	// New keywords for extended SQL support
104	Case,
105	When,
106	Then,
107	Else,
108	End,
109	Exists,
110	Union,
111	All,
112	Intersect,
113	Except,
114	Like,
115	Glob,
116	If,
117	FloatKw,
118	Index,
119	Unique,
120	Drop,
121	Cross,
122	Outer,
123	Full,
124	Natural,
125	Numeric,
126}
127
128pub fn tokenize(sql: &str) -> Result<Vec<Token>, Error> {
129	let mut tokens = Vec::new();
130	let chars: Vec<char> = sql.chars().collect();
131	let len = chars.len();
132	let mut i = 0;
133
134	while i < len {
135		let c = chars[i];
136
137		// Skip whitespace
138		if c.is_ascii_whitespace() {
139			i += 1;
140			continue;
141		}
142
143		// Skip line comments (-- ...)
144		if c == '-' && i + 1 < len && chars[i + 1] == '-' {
145			while i < len && chars[i] != '\n' {
146				i += 1;
147			}
148			continue;
149		}
150
151		// Operators and punctuation
152		match c {
153			'*' => {
154				tokens.push(Token::Asterisk);
155				i += 1;
156				continue;
157			}
158			',' => {
159				tokens.push(Token::Comma);
160				i += 1;
161				continue;
162			}
163			'.' => {
164				tokens.push(Token::Dot);
165				i += 1;
166				continue;
167			}
168			';' => {
169				tokens.push(Token::Semicolon);
170				i += 1;
171				continue;
172			}
173			'(' => {
174				tokens.push(Token::OpenParen);
175				i += 1;
176				continue;
177			}
178			')' => {
179				tokens.push(Token::CloseParen);
180				i += 1;
181				continue;
182			}
183			'+' => {
184				tokens.push(Token::Plus);
185				i += 1;
186				continue;
187			}
188			'-' => {
189				tokens.push(Token::Minus);
190				i += 1;
191				continue;
192			}
193			'/' => {
194				tokens.push(Token::Slash);
195				i += 1;
196				continue;
197			}
198			'%' => {
199				tokens.push(Token::Percent);
200				i += 1;
201				continue;
202			}
203			'=' => {
204				tokens.push(Token::Eq);
205				i += 1;
206				continue;
207			}
208			'<' => {
209				if i + 1 < len && chars[i + 1] == '=' {
210					tokens.push(Token::LtEq);
211					i += 2;
212				} else if i + 1 < len && chars[i + 1] == '>' {
213					tokens.push(Token::NotEq);
214					i += 2;
215				} else {
216					tokens.push(Token::Lt);
217					i += 1;
218				}
219				continue;
220			}
221			'>' => {
222				if i + 1 < len && chars[i + 1] == '=' {
223					tokens.push(Token::GtEq);
224					i += 2;
225				} else {
226					tokens.push(Token::Gt);
227					i += 1;
228				}
229				continue;
230			}
231			'!' => {
232				if i + 1 < len && chars[i + 1] == '=' {
233					tokens.push(Token::NotEq);
234					i += 2;
235					continue;
236				}
237				return Err(Error(format!("unexpected character '!' at position {i}")));
238			}
239			'|' => {
240				if i + 1 < len && chars[i + 1] == '|' {
241					tokens.push(Token::Concat);
242					i += 2;
243					continue;
244				}
245				return Err(Error(format!("unexpected character '|' at position {i}")));
246			}
247			_ => {}
248		}
249
250		// String literals
251		if c == '\'' {
252			i += 1;
253			let mut s = String::new();
254			while i < len {
255				if chars[i] == '\'' {
256					// Check for escaped single quote ''
257					if i + 1 < len && chars[i + 1] == '\'' {
258						s.push('\'');
259						i += 2;
260					} else {
261						break;
262					}
263				} else {
264					s.push(chars[i]);
265					i += 1;
266				}
267			}
268			if i >= len {
269				return Err(Error("unterminated string literal".into()));
270			}
271			i += 1; // skip closing quote
272			tokens.push(Token::StringLit(s));
273			continue;
274		}
275
276		// Numeric literals
277		if c.is_ascii_digit() {
278			let start = i;
279			while i < len && chars[i].is_ascii_digit() {
280				i += 1;
281			}
282			if i < len && chars[i] == '.' && i + 1 < len && chars[i + 1].is_ascii_digit() {
283				i += 1; // skip dot
284				while i < len && chars[i].is_ascii_digit() {
285					i += 1;
286				}
287				let text: String = chars[start..i].iter().collect();
288				let f: f64 = text.parse().map_err(|e| Error(format!("invalid float: {e}")))?;
289				tokens.push(Token::Float(f));
290			} else {
291				let text: String = chars[start..i].iter().collect();
292				let n: i64 = text.parse().map_err(|e| Error(format!("invalid integer: {e}")))?;
293				tokens.push(Token::Integer(n));
294			}
295			continue;
296		}
297
298		// Identifiers and keywords
299		if c.is_ascii_alphabetic() || c == '_' {
300			let start = i;
301			while i < len && (chars[i].is_ascii_alphanumeric() || chars[i] == '_') {
302				i += 1;
303			}
304			let word: String = chars[start..i].iter().collect();
305			let upper = word.to_ascii_uppercase();
306			let token = match upper.as_str() {
307				"SELECT" => Token::Keyword(Keyword::Select),
308				"FROM" => Token::Keyword(Keyword::From),
309				"WHERE" => Token::Keyword(Keyword::Where),
310				"AND" => Token::Keyword(Keyword::And),
311				"OR" => Token::Keyword(Keyword::Or),
312				"NOT" => Token::Keyword(Keyword::Not),
313				"AS" => Token::Keyword(Keyword::As),
314				"ORDER" => Token::Keyword(Keyword::Order),
315				"BY" => Token::Keyword(Keyword::By),
316				"ASC" => Token::Keyword(Keyword::Asc),
317				"DESC" => Token::Keyword(Keyword::Desc),
318				"LIMIT" => Token::Keyword(Keyword::Limit),
319				"OFFSET" => Token::Keyword(Keyword::Offset),
320				"GROUP" => Token::Keyword(Keyword::Group),
321				"HAVING" => Token::Keyword(Keyword::Having),
322				"DISTINCT" => Token::Keyword(Keyword::Distinct),
323				"INSERT" => Token::Keyword(Keyword::Insert),
324				"INTO" => Token::Keyword(Keyword::Into),
325				"VALUES" => Token::Keyword(Keyword::Values),
326				"UPDATE" => Token::Keyword(Keyword::Update),
327				"SET" => Token::Keyword(Keyword::Set),
328				"DELETE" => Token::Keyword(Keyword::Delete),
329				"CREATE" => Token::Keyword(Keyword::Create),
330				"TABLE" => Token::Keyword(Keyword::Table),
331				"JOIN" => Token::Keyword(Keyword::Join),
332				"INNER" => Token::Keyword(Keyword::Inner),
333				"LEFT" => Token::Keyword(Keyword::Left),
334				"RIGHT" => Token::Keyword(Keyword::Right),
335				"ON" => Token::Keyword(Keyword::On),
336				"NULL" => Token::Keyword(Keyword::Null),
337				"TRUE" => Token::Keyword(Keyword::True),
338				"FALSE" => Token::Keyword(Keyword::False),
339				"IS" => Token::Keyword(Keyword::Is),
340				"IN" => Token::Keyword(Keyword::In),
341				"BETWEEN" => Token::Keyword(Keyword::Between),
342				"CAST" => Token::Keyword(Keyword::Cast),
343				"COUNT" => Token::Keyword(Keyword::Count),
344				"SUM" => Token::Keyword(Keyword::Sum),
345				"AVG" => Token::Keyword(Keyword::Avg),
346				"MIN" => Token::Keyword(Keyword::Min),
347				"MAX" => Token::Keyword(Keyword::Max),
348				"INT" => Token::Keyword(Keyword::Int),
349				"INT2" => Token::Keyword(Keyword::Int2),
350				"INT4" => Token::Keyword(Keyword::Int4),
351				"INT8" => Token::Keyword(Keyword::Int8),
352				"SMALLINT" => Token::Keyword(Keyword::Smallint),
353				"INTEGER" => Token::Keyword(Keyword::Integer),
354				"BIGINT" => Token::Keyword(Keyword::Bigint),
355				"FLOAT4" => Token::Keyword(Keyword::Float4),
356				"FLOAT8" => Token::Keyword(Keyword::Float8),
357				"REAL" => Token::Keyword(Keyword::Real),
358				"DOUBLE" => Token::Keyword(Keyword::Double),
359				"PRECISION" => Token::Keyword(Keyword::Precision),
360				"BOOLEAN" => Token::Keyword(Keyword::Boolean),
361				"BOOL" => Token::Keyword(Keyword::Bool),
362				"VARCHAR" => Token::Keyword(Keyword::Varchar),
363				"TEXT" => Token::Keyword(Keyword::Text),
364				"CHAR" => Token::Keyword(Keyword::Char),
365				"UTF8" => Token::Keyword(Keyword::Utf8),
366				"BLOB" => Token::Keyword(Keyword::Blob),
367				"PRIMARY" => Token::Keyword(Keyword::Primary),
368				"KEY" => Token::Keyword(Keyword::Key),
369				"WITH" => Token::Keyword(Keyword::With),
370				"RECURSIVE" => Token::Keyword(Keyword::Recursive),
371				"CASE" => Token::Keyword(Keyword::Case),
372				"WHEN" => Token::Keyword(Keyword::When),
373				"THEN" => Token::Keyword(Keyword::Then),
374				"ELSE" => Token::Keyword(Keyword::Else),
375				"END" => Token::Keyword(Keyword::End),
376				"EXISTS" => Token::Keyword(Keyword::Exists),
377				"UNION" => Token::Keyword(Keyword::Union),
378				"ALL" => Token::Keyword(Keyword::All),
379				"INTERSECT" => Token::Keyword(Keyword::Intersect),
380				"EXCEPT" => Token::Keyword(Keyword::Except),
381				"LIKE" => Token::Keyword(Keyword::Like),
382				"GLOB" => Token::Keyword(Keyword::Glob),
383				"IF" => Token::Keyword(Keyword::If),
384				"FLOAT" => Token::Keyword(Keyword::FloatKw),
385				"INDEX" => Token::Keyword(Keyword::Index),
386				"UNIQUE" => Token::Keyword(Keyword::Unique),
387				"DROP" => Token::Keyword(Keyword::Drop),
388				"CROSS" => Token::Keyword(Keyword::Cross),
389				"OUTER" => Token::Keyword(Keyword::Outer),
390				"FULL" => Token::Keyword(Keyword::Full),
391				"NATURAL" => Token::Keyword(Keyword::Natural),
392				"NUMERIC" => Token::Keyword(Keyword::Numeric),
393				_ => Token::Ident(word),
394			};
395			tokens.push(token);
396			continue;
397		}
398
399		return Err(Error(format!("unexpected character '{c}' at position {i}")));
400	}
401
402	Ok(tokens)
403}
404
405#[cfg(test)]
406mod tests {
407	use super::*;
408
409	#[test]
410	fn test_simple_select() {
411		let tokens = tokenize("SELECT id, name FROM users").unwrap();
412		assert_eq!(
413			tokens,
414			vec![
415				Token::Keyword(Keyword::Select),
416				Token::Ident("id".into()),
417				Token::Comma,
418				Token::Ident("name".into()),
419				Token::Keyword(Keyword::From),
420				Token::Ident("users".into()),
421			]
422		);
423	}
424
425	#[test]
426	fn test_string_literal() {
427		let tokens = tokenize("SELECT 'hello'").unwrap();
428		assert_eq!(tokens, vec![Token::Keyword(Keyword::Select), Token::StringLit("hello".into()),]);
429	}
430
431	#[test]
432	fn test_comparison_operators() {
433		let tokens = tokenize("a <> b").unwrap();
434		assert_eq!(tokens, vec![Token::Ident("a".into()), Token::NotEq, Token::Ident("b".into()),]);
435	}
436
437	#[test]
438	fn test_numeric_literals() {
439		let tokens = tokenize("42 3.14").unwrap();
440		assert_eq!(tokens, vec![Token::Integer(42), Token::Float(3.14),]);
441	}
442}
reifydb_sql/token.rs

reifydb_sql/
token.rs
