Architecture Changes:
- Split dialect implementations into separate files for better organization
- Move SQLite dialect from dialect.go to sqlite.go
- Keep only Dialect interface in dialect.go with comprehensive documentation
- Each dialect now in its own file following single responsibility principle
New Features:
- Add PostgreSQL dialect support (Postgres() function)
- PostgreSQL uses SERIAL PRIMARY KEY (auto-incrementing integer)
- PostgreSQL uses $1, $2 placeholders instead of ? for parameters
- PostgreSQL uses SELECT 1 for table existence check (more efficient)
- Both dialects implement proper SQL identifier quoting for security
Testing:
- Add comprehensive dialect-specific tests in sqlite_test.go
- Add comprehensive dialect-specific tests in postgres_test.go
- Test SQL generation for all dialect methods
- Test SQL injection protection via identifier escaping
- All tests pass (8 test functions, 10 subtests)
Documentation:
- Update README with PostgreSQL usage example
- Add "Supported Databases" section listing SQLite and PostgreSQL
- Improve code examples with proper imports and error handling
- Document how to implement Dialect interface for other databases
File Structure:
- dialect.go: Interface definition only (18 lines)
- sqlite.go: SQLite dialect implementation (39 lines)
- postgres.go: PostgreSQL dialect implementation (42 lines)
- sqlite_test.go: SQLite dialect tests (67 lines)
- postgres_test.go: PostgreSQL dialect tests (67 lines)
Security:
- Both dialects use quoteIdentifier() for SQL injection protection
- Identifiers are quoted and internal quotes are escaped
- Follows SQL standard quoting mechanism (double quotes for escaping)
This change maintains backward compatibility while adding PostgreSQL support
and improving code organization for future dialect additions.
Security Fixes:
- Add SQL injection protection in dialect.go using proper identifier quoting
- Implement quoteIdentifier() method to escape SQL identifiers safely
- Fix resource leak in dbVersion() by adding deferred rows.Close()
- Fix incorrect error handling in dbVersion() to properly propagate errors
Code Quality Improvements:
- Replace custom Error struct with idiomatic fmt.Errorf with %w verb
- Simplify error handling by replacing nested if-err-nil with early returns
- Remove named return values with implicit returns for clarity
- Update interface{} to any (Go 1.18+ style)
- Fix variable shadowing in Apply loop (use m.Description instead of migrations[i])
Test Improvements:
- Fix variable shadowing bug in createTestDB() that caused nil pointer panics
- Update SQL driver from github.com/mattn/go-sqlite3 to modernc.org/sqlite
- Fix driver name from "sqlite3" to "sqlite" for modernc.org/sqlite
- Add missing error check for r.Scan() in TestApply
- Make test error handling consistent by using t.Fatal() throughout
- Simplify test helper functions with early returns
Documentation Fixes:
- Fix README example to use 'Apply' field instead of incorrect 'F' field
- Update README example to match actual test code (sex instead of gender)
- Fix typos: "datbase" → "database", "datbases" → "databases"
- Improve README clarity with proper punctuation and formatting
- Update doc.go with correct spelling
Dependencies:
- Update go.mod to Go 1.25
- Switch to modernc.org/sqlite v1.44.0 (pure Go SQLite driver)
- Add all required indirect dependencies
All changes maintain backward compatibility and pass existing tests.
