Implement pretty formatting option for CREATE TABLE statements

- Add pretty option to DeparserOptions interface
- Enhance SqlFormatter with proper indentation support
- Modify CreateStmt to format with newlines and tabs when pretty=true
- Create new pretty/ test folder with snapshot tests
- Maintain backward compatibility (pretty=false by default)
- All existing tests continue to pass

Co-Authored-By: Dan Lynch <[email protected]>

Author: devin-ai-integration[bot]

__fixtures__/pretty/create_table.sql

@@ -0,0 +1,39 @@
+
+CREATE TABLE users (
+  id SERIAL PRIMARY KEY,
+  name TEXT NOT NULL,
+  email TEXT UNIQUE
+);
+
+CREATE TABLE products (
+  id SERIAL PRIMARY KEY,
+  name VARCHAR(255) NOT NULL,
+  price DECIMAL(10,2) CHECK (price > 0),
+  category_id INTEGER,
+  description TEXT,
+  created_at TIMESTAMP DEFAULT now(),
+  updated_at TIMESTAMP,
+  UNIQUE (name, category_id),
+  FOREIGN KEY (category_id) REFERENCES categories(id)
+);
+
+CREATE TABLE orders (
+  id SERIAL PRIMARY KEY,
+  subtotal DECIMAL(10,2) NOT NULL,
+  tax_rate DECIMAL(5,4) DEFAULT 0.0825,
+  tax_amount DECIMAL(10,2) GENERATED ALWAYS AS (subtotal * tax_rate) STORED,
+  total DECIMAL(10,2) GENERATED ALWAYS AS (subtotal + tax_amount) STORED
+);
+
+CREATE TABLE sales (
+  id SERIAL,
+  sale_date DATE NOT NULL,
+  amount DECIMAL(10,2),
+  region VARCHAR(50)
+) PARTITION BY RANGE (sale_date);
+
+CREATE TEMPORARY TABLE temp_calculations (
+  id INTEGER,
+  value DECIMAL(15,5),
+  result TEXT
+);

packages/deparser/__tests__/pretty/__snapshots__/create-table-pretty.test.ts.snap

@@ -0,0 +1,32 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Pretty CREATE TABLE formatting should format basic CREATE TABLE with pretty option enabled 1`] = `
+"CREATE TABLE users (
+  id serial PRIMARY KEY,
+  name text NOT NULL,
+  email text UNIQUE
+);"
+`;
+
+exports[`Pretty CREATE TABLE formatting should format complex CREATE TABLE with pretty option enabled 1`] = `
+"CREATE TABLE orders (
+  id serial PRIMARY KEY,
+  user_id int NOT NULL,
+  total numeric(10, 2) CHECK (total > 0),
+  status varchar(20) DEFAULT 'pending',
+  created_at pg_catalog.timestamp DEFAULT now(),
+  FOREIGN KEY (user_id) REFERENCES users (id)
+);"
+`;
+
+exports[`Pretty CREATE TABLE formatting should maintain single-line format for complex table when pretty disabled 1`] = `"CREATE TABLE orders (id serial PRIMARY KEY, user_id int NOT NULL, total numeric(10, 2) CHECK (total > 0), status varchar(20) DEFAULT 'pending', created_at pg_catalog.timestamp DEFAULT now(), FOREIGN KEY (user_id) REFERENCES users (id));"`;
+
+exports[`Pretty CREATE TABLE formatting should maintain single-line format when pretty option disabled 1`] = `"CREATE TABLE users (id serial PRIMARY KEY, name text NOT NULL, email text UNIQUE);"`;
+
+exports[`Pretty CREATE TABLE formatting should use custom newline and tab characters in pretty mode 1`] = `
+"CREATE TABLE users (
+    id serial PRIMARY KEY,
+    name text NOT NULL,
+    email text UNIQUE
+);"
+`;

packages/deparser/__tests__/pretty/create-table-pretty.test.ts

@@ -0,0 +1,49 @@
+import { deparseSync } from '../../src';
+import { parse } from 'libpg-query';
+
+describe('Pretty CREATE TABLE formatting', () => {
+  const basicTableSql = `CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT NOT NULL, email TEXT UNIQUE);`;
+  
+  const complexTableSql = `CREATE TABLE orders (
+    id SERIAL PRIMARY KEY,
+    user_id INTEGER NOT NULL,
+    total DECIMAL(10,2) CHECK (total > 0),
+    status VARCHAR(20) DEFAULT 'pending',
+    created_at TIMESTAMP DEFAULT now(),
+    FOREIGN KEY (user_id) REFERENCES users(id)
+  );`;
+
+  it('should format basic CREATE TABLE with pretty option enabled', async () => {
+    const parsed = await parse(basicTableSql);
+    const result = deparseSync(parsed, { pretty: true });
+    expect(result).toMatchSnapshot();
+  });
+
+  it('should maintain single-line format when pretty option disabled', async () => {
+    const parsed = await parse(basicTableSql);
+    const result = deparseSync(parsed, { pretty: false });
+    expect(result).toMatchSnapshot();
+  });
+
+  it('should format complex CREATE TABLE with pretty option enabled', async () => {
+    const parsed = await parse(complexTableSql);
+    const result = deparseSync(parsed, { pretty: true });
+    expect(result).toMatchSnapshot();
+  });
+
+  it('should maintain single-line format for complex table when pretty disabled', async () => {
+    const parsed = await parse(complexTableSql);
+    const result = deparseSync(parsed, { pretty: false });
+    expect(result).toMatchSnapshot();
+  });
+
+  it('should use custom newline and tab characters in pretty mode', async () => {
+    const parsed = await parse(basicTableSql);
+    const result = deparseSync(parsed, { 
+      pretty: true, 
+      newline: '\r\n', 
+      tab: '    ' 
+    });
+    expect(result).toMatchSnapshot();
+  });
+});

packages/deparser/src/deparser.ts

@@ -12,6 +12,7 @@ export interface DeparserOptions {
   functionDelimiter?: string;  // Default: '$$'
   // Alternative delimiter when the default is found in the body
   functionDelimiterFallback?: string;  // Default: '$EOFCODE$'
+  pretty?: boolean;  // Default: false
 }
 
 // Type guards for better type safety
@@ -64,7 +65,7 @@ export class Deparser implements DeparserVisitor {
   private options: DeparserOptions;
 
   constructor(tree: Node | Node[] | t.ParseResult, opts: DeparserOptions = {}) {
-    this.formatter = new SqlFormatter(opts.newline, opts.tab);
+    this.formatter = new SqlFormatter(opts.newline, opts.tab, opts.pretty);
 
     // Set default options
     this.options = {
@@ -2139,7 +2140,15 @@ export class Deparser implements DeparserVisitor {
       const elementStrs = elements.map(el => {
         return this.deparse(el, context);
       });
-      output.push(this.formatter.parens(elementStrs.join(', ')));
+      
+      if (this.formatter.isPretty()) {
+        const formattedElements = elementStrs.map(el => 
+          this.formatter.indent(el)
+        ).join(',' + this.formatter.newline());
+        output.push('(' + this.formatter.newline() + formattedElements + this.formatter.newline() + ')');
+      } else {
+        output.push(this.formatter.parens(elementStrs.join(', ')));
+      }
     } else if (!node.partbound) {
       output.push(this.formatter.parens(''));
     }

packages/deparser/src/utils/sql-formatter.ts

@@ -1,18 +1,26 @@
 export class SqlFormatter {
   private newlineChar: string;
   private tabChar: string;
+  private prettyMode: boolean;
 
-  constructor(newlineChar: string = '\n', tabChar: string = '  ') {
+  constructor(newlineChar: string = '\n', tabChar: string = '  ', prettyMode: boolean = false) {
     this.newlineChar = newlineChar;
     this.tabChar = tabChar;
+    this.prettyMode = prettyMode;
   }
 
   format(parts: string[], separator: string = ' '): string {
     return parts.filter(part => part !== null && part !== undefined && part !== '').join(separator);
   }
 
   indent(text: string, count: number = 1): string {
-    return text;
+    if (!this.prettyMode) {
+      return text;
+    }
+    const indentation = this.tabChar.repeat(count);
+    return text.split(this.newlineChar).map(line => 
+      line.trim() ? indentation + line : line
+    ).join(this.newlineChar);
   }
 
   parens(content: string): string {
@@ -26,4 +34,8 @@ export class SqlFormatter {
   tab(): string {
     return this.tabChar;
   }
+
+  isPretty(): boolean {
+    return this.prettyMode;
+  }
 }