sql_cli/sql/parser/
ast_formatter.rs

1//! AST-based SQL Formatter
2//!
3//! This module provides proper SQL formatting by traversing the parsed AST,
4//! which is more reliable than regex-based formatting and handles complex
5//! features like CTEs, subqueries, and expressions correctly.
6
7use crate::sql::parser::ast::*;
8use std::fmt::Write;
9
10/// Configuration for SQL formatting
11pub struct FormatConfig {
12    /// Indentation string (e.g., "  " for 2 spaces, "\t" for tab)
13    pub indent: String,
14    /// Maximum number of items per line for lists (SELECT columns, etc.)
15    pub items_per_line: usize,
16    /// Whether to uppercase keywords
17    pub uppercase_keywords: bool,
18    /// Whether to add newlines between major clauses
19    pub compact: bool,
20}
21
22impl Default for FormatConfig {
23    fn default() -> Self {
24        Self {
25            indent: "    ".to_string(),
26            items_per_line: 5,
27            uppercase_keywords: true,
28            compact: false,
29        }
30    }
31}
32
33/// Format a SELECT statement into pretty SQL
34pub fn format_select_statement(stmt: &SelectStatement) -> String {
35    format_select_with_config(stmt, &FormatConfig::default())
36}
37
38/// Format a SELECT statement with custom configuration
39pub fn format_select_with_config(stmt: &SelectStatement, config: &FormatConfig) -> String {
40    let formatter = AstFormatter::new(config);
41    formatter.format_select(stmt, 0)
42}
43
44struct AstFormatter<'a> {
45    config: &'a FormatConfig,
46}
47
48impl<'a> AstFormatter<'a> {
49    fn new(config: &'a FormatConfig) -> Self {
50        Self { config }
51    }
52
53    fn keyword(&self, word: &str) -> String {
54        if self.config.uppercase_keywords {
55            word.to_uppercase()
56        } else {
57            word.to_lowercase()
58        }
59    }
60
61    fn indent(&self, level: usize) -> String {
62        self.config.indent.repeat(level)
63    }
64
65    fn format_select(&self, stmt: &SelectStatement, indent_level: usize) -> String {
66        let mut result = String::new();
67        let indent = self.indent(indent_level);
68
69        // CTEs (WITH clause)
70        if !stmt.ctes.is_empty() {
71            writeln!(&mut result, "{}{}", indent, self.keyword("WITH")).unwrap();
72            for (i, cte) in stmt.ctes.iter().enumerate() {
73                let is_last = i == stmt.ctes.len() - 1;
74                self.format_cte(&mut result, cte, indent_level + 1, is_last);
75            }
76        }
77
78        // SELECT clause
79        write!(&mut result, "{}{}", indent, self.keyword("SELECT")).unwrap();
80        if stmt.distinct {
81            write!(&mut result, " {}", self.keyword("DISTINCT")).unwrap();
82        }
83
84        // Format select items
85        if stmt.select_items.is_empty() && !stmt.columns.is_empty() {
86            // Legacy columns field
87            self.format_column_list(&mut result, &stmt.columns, indent_level);
88        } else {
89            self.format_select_items(&mut result, &stmt.select_items, indent_level);
90        }
91
92        // FROM clause
93        if let Some(ref table) = stmt.from_table {
94            writeln!(&mut result).unwrap();
95            write!(&mut result, "{}{} {}", indent, self.keyword("FROM"), table).unwrap();
96        } else if let Some(ref subquery) = stmt.from_subquery {
97            writeln!(&mut result).unwrap();
98            write!(&mut result, "{}{} (", indent, self.keyword("FROM")).unwrap();
99            writeln!(&mut result).unwrap();
100            let subquery_sql = self.format_select(subquery, indent_level + 1);
101            write!(&mut result, "{}", subquery_sql).unwrap();
102            write!(&mut result, "\n{}", indent).unwrap();
103            write!(&mut result, ")").unwrap();
104            if let Some(ref alias) = stmt.from_alias {
105                write!(&mut result, " {} {}", self.keyword("AS"), alias).unwrap();
106            }
107        } else if let Some(ref func) = stmt.from_function {
108            writeln!(&mut result).unwrap();
109            write!(&mut result, "{}{} ", indent, self.keyword("FROM")).unwrap();
110            self.format_table_function(&mut result, func);
111            if let Some(ref alias) = stmt.from_alias {
112                write!(&mut result, " {} {}", self.keyword("AS"), alias).unwrap();
113            }
114        }
115
116        // JOIN clauses
117        for join in &stmt.joins {
118            writeln!(&mut result).unwrap();
119            self.format_join(&mut result, join, indent_level);
120        }
121
122        // WHERE clause
123        if let Some(ref where_clause) = stmt.where_clause {
124            writeln!(&mut result).unwrap();
125            write!(&mut result, "{}{}", indent, self.keyword("WHERE")).unwrap();
126            self.format_where_clause(&mut result, where_clause, indent_level);
127        }
128
129        // GROUP BY clause
130        if let Some(ref group_by) = stmt.group_by {
131            writeln!(&mut result).unwrap();
132            write!(&mut result, "{}{} ", indent, self.keyword("GROUP BY")).unwrap();
133            for (i, expr) in group_by.iter().enumerate() {
134                if i > 0 {
135                    write!(&mut result, ", ").unwrap();
136                }
137                write!(&mut result, "{}", self.format_expression(expr)).unwrap();
138            }
139        }
140
141        // HAVING clause
142        if let Some(ref having) = stmt.having {
143            writeln!(&mut result).unwrap();
144            write!(
145                &mut result,
146                "{}{} {}",
147                indent,
148                self.keyword("HAVING"),
149                self.format_expression(having)
150            )
151            .unwrap();
152        }
153
154        // ORDER BY clause
155        if let Some(ref order_by) = stmt.order_by {
156            writeln!(&mut result).unwrap();
157            write!(&mut result, "{}{} ", indent, self.keyword("ORDER BY")).unwrap();
158            for (i, col) in order_by.iter().enumerate() {
159                if i > 0 {
160                    write!(&mut result, ", ").unwrap();
161                }
162                write!(&mut result, "{}", col.column).unwrap();
163                match col.direction {
164                    SortDirection::Asc => write!(&mut result, " {}", self.keyword("ASC")).unwrap(),
165                    SortDirection::Desc => {
166                        write!(&mut result, " {}", self.keyword("DESC")).unwrap()
167                    }
168                }
169            }
170        }
171
172        // LIMIT clause
173        if let Some(limit) = stmt.limit {
174            writeln!(&mut result).unwrap();
175            write!(&mut result, "{}{} {}", indent, self.keyword("LIMIT"), limit).unwrap();
176        }
177
178        // OFFSET clause
179        if let Some(offset) = stmt.offset {
180            writeln!(&mut result).unwrap();
181            write!(
182                &mut result,
183                "{}{} {}",
184                indent,
185                self.keyword("OFFSET"),
186                offset
187            )
188            .unwrap();
189        }
190
191        result
192    }
193
194    fn format_cte(&self, result: &mut String, cte: &CTE, indent_level: usize, is_last: bool) {
195        let indent = self.indent(indent_level);
196
197        // Add WEB keyword for Web CTEs
198        let is_web = matches!(&cte.cte_type, crate::sql::parser::ast::CTEType::Web(_));
199        if is_web {
200            write!(result, "{}{} {}", indent, self.keyword("WEB"), cte.name).unwrap();
201        } else {
202            write!(result, "{}{}", indent, cte.name).unwrap();
203        }
204
205        if let Some(ref columns) = cte.column_list {
206            write!(result, "(").unwrap();
207            for (i, col) in columns.iter().enumerate() {
208                if i > 0 {
209                    write!(result, ", ").unwrap();
210                }
211                write!(result, "{}", col).unwrap();
212            }
213            write!(result, ")").unwrap();
214        }
215
216        writeln!(result, " {} (", self.keyword("AS")).unwrap();
217        let cte_sql = match &cte.cte_type {
218            crate::sql::parser::ast::CTEType::Standard(query) => {
219                self.format_select(query, indent_level + 1)
220            }
221            crate::sql::parser::ast::CTEType::Web(web_spec) => {
222                // Format WEB CTE
223                let mut web_str = format!(
224                    "{}{} '{}'",
225                    "    ".repeat(indent_level + 1),
226                    self.keyword("URL"),
227                    web_spec.url
228                );
229
230                // Add METHOD if specified
231                if let Some(method) = &web_spec.method {
232                    web_str.push_str(&format!(
233                        " {} {}",
234                        self.keyword("METHOD"),
235                        match method {
236                            crate::sql::parser::ast::HttpMethod::GET => "GET",
237                            crate::sql::parser::ast::HttpMethod::POST => "POST",
238                            crate::sql::parser::ast::HttpMethod::PUT => "PUT",
239                            crate::sql::parser::ast::HttpMethod::DELETE => "DELETE",
240                            crate::sql::parser::ast::HttpMethod::PATCH => "PATCH",
241                        }
242                    ));
243                }
244
245                // Add BODY if specified
246                if let Some(body) = &web_spec.body {
247                    web_str.push_str(&format!(" {} '{}'", self.keyword("BODY"), body));
248                }
249
250                // Add FORMAT if specified
251                if let Some(format) = &web_spec.format {
252                    web_str.push_str(&format!(
253                        " {} {}",
254                        self.keyword("FORMAT"),
255                        match format {
256                            crate::sql::parser::ast::DataFormat::CSV => "CSV",
257                            crate::sql::parser::ast::DataFormat::JSON => "JSON",
258                            crate::sql::parser::ast::DataFormat::Auto => "AUTO",
259                        }
260                    ));
261                }
262
263                // Add JSON_PATH if specified
264                if let Some(json_path) = &web_spec.json_path {
265                    web_str.push_str(&format!(" {} '{}'", self.keyword("JSON_PATH"), json_path));
266                }
267
268                // Add CACHE if specified
269                if let Some(cache) = web_spec.cache_seconds {
270                    web_str.push_str(&format!(" {} {}", self.keyword("CACHE"), cache));
271                }
272
273                // Add HEADERS if specified
274                if !web_spec.headers.is_empty() {
275                    web_str.push_str(&format!(" {} (", self.keyword("HEADERS")));
276                    for (i, (key, value)) in web_spec.headers.iter().enumerate() {
277                        if i > 0 {
278                            web_str.push_str(", ");
279                        }
280                        web_str.push_str(&format!("'{}': '{}'", key, value));
281                    }
282                    web_str.push(')');
283                }
284
285                web_str
286            }
287        };
288        write!(result, "{}", cte_sql).unwrap();
289        writeln!(result).unwrap();
290        write!(result, "{}", indent).unwrap();
291        if is_last {
292            writeln!(result, ")").unwrap();
293        } else {
294            writeln!(result, "),").unwrap();
295        }
296    }
297
298    fn format_column_list(&self, result: &mut String, columns: &[String], indent_level: usize) {
299        if columns.len() <= self.config.items_per_line {
300            // Single line
301            write!(result, " ").unwrap();
302            for (i, col) in columns.iter().enumerate() {
303                if i > 0 {
304                    write!(result, ", ").unwrap();
305                }
306                write!(result, "{}", col).unwrap();
307            }
308        } else {
309            // Multi-line
310            writeln!(result).unwrap();
311            let indent = self.indent(indent_level + 1);
312            for (i, col) in columns.iter().enumerate() {
313                write!(result, "{}{}", indent, col).unwrap();
314                if i < columns.len() - 1 {
315                    writeln!(result, ",").unwrap();
316                }
317            }
318        }
319    }
320
321    fn format_select_items(&self, result: &mut String, items: &[SelectItem], indent_level: usize) {
322        if items.is_empty() {
323            write!(result, " *").unwrap();
324            return;
325        }
326
327        // Count non-star items for formatting decision
328        let non_star_count = items
329            .iter()
330            .filter(|i| !matches!(i, SelectItem::Star))
331            .count();
332
333        // Check if any item is complex (function calls, CASE expressions, etc.)
334        let has_complex_items = items.iter().any(|item| match item {
335            SelectItem::Expression { expr, .. } => self.is_complex_expression(expr),
336            _ => false,
337        });
338
339        // Calculate total approximate length if on single line
340        let single_line_length: usize = items
341            .iter()
342            .map(|item| {
343                match item {
344                    SelectItem::Star => 1,
345                    SelectItem::Column(col) => col.name.len(),
346                    SelectItem::Expression { expr, alias } => {
347                        self.format_expression(expr).len() + 4 + alias.len() // " AS " = 4
348                    }
349                }
350            })
351            .sum::<usize>()
352            + (items.len() - 1) * 2; // ", " between items
353
354        // Use multi-line formatting by default unless:
355        // - It's a single simple column or star
356        // - It's 2-3 simple columns with total length < 40 chars
357        let use_single_line = match items.len() {
358            1 => !has_complex_items, // Single item: only if simple
359            2..=3 => !has_complex_items && single_line_length < 40, // 2-3 items: only if very short
360            _ => false,              // 4+ items: always multi-line
361        };
362
363        if !use_single_line {
364            // Multi-line
365            writeln!(result).unwrap();
366            let indent = self.indent(indent_level + 1);
367            for (i, item) in items.iter().enumerate() {
368                write!(result, "{}", indent).unwrap();
369                self.format_select_item(result, item);
370                if i < items.len() - 1 {
371                    writeln!(result, ",").unwrap();
372                }
373            }
374        } else {
375            // Single line
376            write!(result, " ").unwrap();
377            for (i, item) in items.iter().enumerate() {
378                if i > 0 {
379                    write!(result, ", ").unwrap();
380                }
381                self.format_select_item(result, item);
382            }
383        }
384    }
385
386    fn is_complex_expression(&self, expr: &SqlExpression) -> bool {
387        match expr {
388            SqlExpression::CaseExpression { .. } => true,
389            SqlExpression::FunctionCall { .. } => true,
390            SqlExpression::WindowFunction { .. } => true,
391            SqlExpression::ScalarSubquery { .. } => true,
392            SqlExpression::InSubquery { .. } => true,
393            SqlExpression::NotInSubquery { .. } => true,
394            SqlExpression::BinaryOp { left, right, .. } => {
395                self.is_complex_expression(left) || self.is_complex_expression(right)
396            }
397            _ => false,
398        }
399    }
400
401    fn format_select_item(&self, result: &mut String, item: &SelectItem) {
402        match item {
403            SelectItem::Star => write!(result, "*").unwrap(),
404            SelectItem::Column(col) => write!(result, "{}", col.to_sql()).unwrap(),
405            SelectItem::Expression { expr, alias } => {
406                write!(
407                    result,
408                    "{} {} {}",
409                    self.format_expression(expr),
410                    self.keyword("AS"),
411                    alias
412                )
413                .unwrap();
414            }
415        }
416    }
417
418    fn format_expression(&self, expr: &SqlExpression) -> String {
419        match expr {
420            SqlExpression::Column(column_ref) => column_ref.to_sql(),
421            SqlExpression::StringLiteral(s) => format!("'{}'", s),
422            SqlExpression::NumberLiteral(n) => n.clone(),
423            SqlExpression::BooleanLiteral(b) => b.to_string().to_uppercase(),
424            SqlExpression::Null => self.keyword("NULL"),
425            SqlExpression::BinaryOp { left, op, right } => {
426                // Special handling for IS NULL / IS NOT NULL operators
427                if op == "IS NULL" || op == "IS NOT NULL" {
428                    format!("{} {}", self.format_expression(left), op)
429                } else {
430                    format!(
431                        "{} {} {}",
432                        self.format_expression(left),
433                        op,
434                        self.format_expression(right)
435                    )
436                }
437            }
438            SqlExpression::FunctionCall {
439                name,
440                args,
441                distinct,
442            } => {
443                let mut result = name.clone();
444                result.push('(');
445                if *distinct {
446                    result.push_str(&self.keyword("DISTINCT"));
447                    result.push(' ');
448                }
449                for (i, arg) in args.iter().enumerate() {
450                    if i > 0 {
451                        result.push_str(", ");
452                    }
453                    result.push_str(&self.format_expression(arg));
454                }
455                result.push(')');
456                result
457            }
458            SqlExpression::CaseExpression {
459                when_branches,
460                else_branch,
461            } => {
462                // Format CASE expressions on multiple lines for readability
463                let mut result = String::new();
464                result.push_str(&self.keyword("CASE"));
465                result.push('\n');
466
467                // Format each WHEN branch on its own line with indentation
468                for branch in when_branches {
469                    result.push_str("        "); // 8 spaces for WHEN indent
470                    result.push_str(&format!(
471                        "{} {} {} {}",
472                        self.keyword("WHEN"),
473                        self.format_expression(&branch.condition),
474                        self.keyword("THEN"),
475                        self.format_expression(&branch.result)
476                    ));
477                    result.push('\n');
478                }
479
480                // Format ELSE clause if present
481                if let Some(else_expr) = else_branch {
482                    result.push_str("        "); // 8 spaces for ELSE indent
483                    result.push_str(&format!(
484                        "{} {}",
485                        self.keyword("ELSE"),
486                        self.format_expression(else_expr)
487                    ));
488                    result.push('\n');
489                }
490
491                result.push_str("    "); // 4 spaces for END
492                result.push_str(&self.keyword("END"));
493                result
494            }
495            SqlExpression::Between { expr, lower, upper } => {
496                format!(
497                    "{} {} {} {} {}",
498                    self.format_expression(expr),
499                    self.keyword("BETWEEN"),
500                    self.format_expression(lower),
501                    self.keyword("AND"),
502                    self.format_expression(upper)
503                )
504            }
505            SqlExpression::InList { expr, values } => {
506                let mut result =
507                    format!("{} {} (", self.format_expression(expr), self.keyword("IN"));
508                for (i, val) in values.iter().enumerate() {
509                    if i > 0 {
510                        result.push_str(", ");
511                    }
512                    result.push_str(&self.format_expression(val));
513                }
514                result.push(')');
515                result
516            }
517            SqlExpression::NotInList { expr, values } => {
518                let mut result = format!(
519                    "{} {} {} (",
520                    self.format_expression(expr),
521                    self.keyword("NOT"),
522                    self.keyword("IN")
523                );
524                for (i, val) in values.iter().enumerate() {
525                    if i > 0 {
526                        result.push_str(", ");
527                    }
528                    result.push_str(&self.format_expression(val));
529                }
530                result.push(')');
531                result
532            }
533            SqlExpression::Not { expr } => {
534                format!("{} {}", self.keyword("NOT"), self.format_expression(expr))
535            }
536            SqlExpression::ScalarSubquery { query } => {
537                // Check if subquery is complex enough to warrant multi-line formatting
538                let subquery_str = self.format_select(query, 0);
539                if subquery_str.contains('\n') || subquery_str.len() > 60 {
540                    // Multi-line formatting
541                    format!("(\n{}\n)", self.format_select(query, 1))
542                } else {
543                    // Inline formatting
544                    format!("({})", subquery_str)
545                }
546            }
547            SqlExpression::InSubquery { expr, subquery } => {
548                let subquery_str = self.format_select(subquery, 0);
549                if subquery_str.contains('\n') || subquery_str.len() > 60 {
550                    // Multi-line formatting
551                    format!(
552                        "{} {} (\n{}\n)",
553                        self.format_expression(expr),
554                        self.keyword("IN"),
555                        self.format_select(subquery, 1)
556                    )
557                } else {
558                    // Inline formatting
559                    format!(
560                        "{} {} ({})",
561                        self.format_expression(expr),
562                        self.keyword("IN"),
563                        subquery_str
564                    )
565                }
566            }
567            SqlExpression::NotInSubquery { expr, subquery } => {
568                let subquery_str = self.format_select(subquery, 0);
569                if subquery_str.contains('\n') || subquery_str.len() > 60 {
570                    // Multi-line formatting
571                    format!(
572                        "{} {} {} (\n{}\n)",
573                        self.format_expression(expr),
574                        self.keyword("NOT"),
575                        self.keyword("IN"),
576                        self.format_select(subquery, 1)
577                    )
578                } else {
579                    // Inline formatting
580                    format!(
581                        "{} {} {} ({})",
582                        self.format_expression(expr),
583                        self.keyword("NOT"),
584                        self.keyword("IN"),
585                        subquery_str
586                    )
587                }
588            }
589            SqlExpression::MethodCall {
590                object,
591                method,
592                args,
593            } => {
594                let mut result = format!("{}.{}", object, method);
595                result.push('(');
596                for (i, arg) in args.iter().enumerate() {
597                    if i > 0 {
598                        result.push_str(", ");
599                    }
600                    result.push_str(&self.format_expression(arg));
601                }
602                result.push(')');
603                result
604            }
605            SqlExpression::ChainedMethodCall { base, method, args } => {
606                let mut result = format!("{}.{}", self.format_expression(base), method);
607                result.push('(');
608                for (i, arg) in args.iter().enumerate() {
609                    if i > 0 {
610                        result.push_str(", ");
611                    }
612                    result.push_str(&self.format_expression(arg));
613                }
614                result.push(')');
615                result
616            }
617            SqlExpression::WindowFunction {
618                name,
619                args,
620                window_spec,
621            } => {
622                let mut result = format!("{}(", name);
623
624                // Add function arguments
625                for (i, arg) in args.iter().enumerate() {
626                    if i > 0 {
627                        result.push_str(", ");
628                    }
629                    result.push_str(&self.format_expression(arg));
630                }
631                result.push_str(") ");
632                result.push_str(&self.keyword("OVER"));
633                result.push_str(" (");
634
635                // Add PARTITION BY clause if present
636                if !window_spec.partition_by.is_empty() {
637                    result.push_str(&self.keyword("PARTITION BY"));
638                    result.push(' ');
639                    for (i, col) in window_spec.partition_by.iter().enumerate() {
640                        if i > 0 {
641                            result.push_str(", ");
642                        }
643                        result.push_str(col);
644                    }
645                }
646
647                // Add ORDER BY clause if present
648                if !window_spec.order_by.is_empty() {
649                    if !window_spec.partition_by.is_empty() {
650                        result.push(' ');
651                    }
652                    result.push_str(&self.keyword("ORDER BY"));
653                    result.push(' ');
654                    for (i, col) in window_spec.order_by.iter().enumerate() {
655                        if i > 0 {
656                            result.push_str(", ");
657                        }
658                        result.push_str(&col.column);
659                        match col.direction {
660                            SortDirection::Asc => {
661                                result.push(' ');
662                                result.push_str(&self.keyword("ASC"));
663                            }
664                            SortDirection::Desc => {
665                                result.push(' ');
666                                result.push_str(&self.keyword("DESC"));
667                            }
668                        }
669                    }
670                }
671
672                result.push(')');
673                result
674            }
675            _ => format!("{:?}", expr), // Fallback for unhandled expression types
676        }
677    }
678
679    fn format_where_clause(
680        &self,
681        result: &mut String,
682        where_clause: &WhereClause,
683        indent_level: usize,
684    ) {
685        let needs_multiline = where_clause.conditions.len() > 1;
686
687        if needs_multiline {
688            writeln!(result).unwrap();
689            let indent = self.indent(indent_level + 1);
690            for (i, condition) in where_clause.conditions.iter().enumerate() {
691                if i > 0 {
692                    if let Some(ref connector) = where_clause.conditions[i - 1].connector {
693                        let connector_str = match connector {
694                            LogicalOp::And => self.keyword("AND"),
695                            LogicalOp::Or => self.keyword("OR"),
696                        };
697                        writeln!(result).unwrap();
698                        write!(result, "{}{} ", indent, connector_str).unwrap();
699                    }
700                } else {
701                    write!(result, "{}", indent).unwrap();
702                }
703                write!(result, "{}", self.format_expression(&condition.expr)).unwrap();
704            }
705        } else if let Some(condition) = where_clause.conditions.first() {
706            write!(result, " {}", self.format_expression(&condition.expr)).unwrap();
707        }
708    }
709
710    fn format_join(&self, result: &mut String, join: &JoinClause, indent_level: usize) {
711        let indent = self.indent(indent_level);
712        let join_type = match join.join_type {
713            JoinType::Inner => self.keyword("INNER JOIN"),
714            JoinType::Left => self.keyword("LEFT JOIN"),
715            JoinType::Right => self.keyword("RIGHT JOIN"),
716            JoinType::Full => self.keyword("FULL JOIN"),
717            JoinType::Cross => self.keyword("CROSS JOIN"),
718        };
719
720        write!(result, "{}{} ", indent, join_type).unwrap();
721
722        match &join.table {
723            TableSource::Table(name) => write!(result, "{}", name).unwrap(),
724            TableSource::DerivedTable { query, alias } => {
725                writeln!(result, "(").unwrap();
726                let subquery_sql = self.format_select(query, indent_level + 1);
727                write!(result, "{}", subquery_sql).unwrap();
728                writeln!(result).unwrap();
729                write!(result, "{}) {} {}", indent, self.keyword("AS"), alias).unwrap();
730            }
731        }
732
733        if let Some(ref alias) = join.alias {
734            write!(result, " {} {}", self.keyword("AS"), alias).unwrap();
735        }
736
737        if !join.condition.conditions.is_empty() {
738            write!(result, " {}", self.keyword("ON")).unwrap();
739            for (i, condition) in join.condition.conditions.iter().enumerate() {
740                if i > 0 {
741                    write!(result, " {}", self.keyword("AND")).unwrap();
742                }
743                write!(
744                    result,
745                    " {} {} {}",
746                    condition.left_column,
747                    self.format_join_operator(&condition.operator),
748                    condition.right_column
749                )
750                .unwrap();
751            }
752        }
753    }
754
755    fn format_join_operator(&self, op: &JoinOperator) -> String {
756        match op {
757            JoinOperator::Equal => "=",
758            JoinOperator::NotEqual => "!=",
759            JoinOperator::LessThan => "<",
760            JoinOperator::GreaterThan => ">",
761            JoinOperator::LessThanOrEqual => "<=",
762            JoinOperator::GreaterThanOrEqual => ">=",
763        }
764        .to_string()
765    }
766
767    fn format_table_function(&self, result: &mut String, func: &TableFunction) {
768        match func {
769            TableFunction::Generator { name, args } => {
770                write!(result, "{}(", self.keyword(&name.to_uppercase())).unwrap();
771                for (i, arg) in args.iter().enumerate() {
772                    if i > 0 {
773                        write!(result, ", ").unwrap();
774                    }
775                    write!(result, "{}", self.format_expression(arg)).unwrap();
776                }
777                write!(result, ")").unwrap();
778            }
779        }
780    }
781}
782
783/// Parse and format SQL query using the AST
784pub fn format_sql_ast(query: &str) -> Result<String, String> {
785    use crate::sql::recursive_parser::Parser;
786
787    let mut parser = Parser::new(query);
788    match parser.parse() {
789        Ok(stmt) => Ok(format_select_statement(&stmt)),
790        Err(e) => Err(format!("Parse error: {}", e)),
791    }
792}
793
794/// Parse and format SQL with custom configuration
795pub fn format_sql_ast_with_config(query: &str, config: &FormatConfig) -> Result<String, String> {
796    use crate::sql::recursive_parser::Parser;
797
798    let mut parser = Parser::new(query);
799    match parser.parse() {
800        Ok(stmt) => Ok(format_select_with_config(&stmt, &config)),
801        Err(e) => Err(format!("Parse error: {}", e)),
802    }
803}
sql_cli/sql/parser/ast_formatter.rs

sql_cli/sql/parser/
ast_formatter.rs
