NCP - Natural Context Provider

/** * Unit tests for FuzzyMatcher utility * Tests Levenshtein distance and suggestion algorithms */ import { FuzzyMatcher } from '../../src/utils/fuzzy-matcher'; describe('FuzzyMatcher', () => { let matcher: FuzzyMatcher; beforeEach(() => { matcher = new FuzzyMatcher(); }); describe('findSuggestions', () => { const commands = ['find', 'run', 'list', 'config', 'auth', 'help']; test('should find exact matches with distance 0', () => { const suggestions = matcher.findSuggestions('find', commands); expect(suggestions).toContain('find'); }); test('should find close matches for single character difference', () => { const suggestions = matcher.findSuggestions('fint', commands); expect(suggestions).toContain('find'); }); test('should find close matches with custom threshold', () => { // 'rnu' -> 'run' requires threshold of 2 (swap n and u) const suggestions = matcher.findSuggestions('rnu', commands, 2); expect(suggestions).toContain('run'); }); test('should find matches for missing character', () => { const suggestions = matcher.findSuggestions('lst', commands); expect(suggestions).toContain('list'); }); test('should find matches for extra character', () => { const suggestions = matcher.findSuggestions('finnd', commands); expect(suggestions).toContain('find'); }); test('should be case insensitive', () => { const suggestions = matcher.findSuggestions('FIND', commands); expect(suggestions).toContain('find'); }); test('should return empty array for very different strings', () => { const suggestions = matcher.findSuggestions('xyz', commands); expect(suggestions.length).toBe(0); }); test('should respect custom distance threshold', () => { const suggestions = matcher.findSuggestions('fint', commands, 0); expect(suggestions.length).toBe(0); // No matches within distance 0 }); test('should return suggestions sorted by similarity (closest first)', () => { const suggestions = matcher.findSuggestions('fin', commands); expect(suggestions[0]).toBe('find'); // Closest match should be first }); test('should return multiple suggestions when available', () => { const suggestions = matcher.findSuggestions('config', commands); expect(suggestions.length).toBeGreaterThan(0); expect(suggestions).toContain('config'); }); }); describe('findBestMatch', () => { const commands = ['find', 'run', 'list', 'config']; test('should return the best single match', () => { const best = matcher.findBestMatch('fint', commands); expect(best).toBe('find'); }); test('should return undefined if no matches found', () => { const best = matcher.findBestMatch('xyz', commands); expect(best).toBeUndefined(); }); test('should return exact match when available', () => { const best = matcher.findBestMatch('find', commands); expect(best).toBe('find'); }); }); describe('isSimilar', () => { test('should return true for identical strings', () => { expect(matcher.isSimilar('hello', 'hello')).toBe(true); }); test('should return true for strings within threshold', () => { expect(matcher.isSimilar('hello', 'helo', 1)).toBe(true); }); test('should return false for strings beyond threshold', () => { expect(matcher.isSimilar('hello', 'xyz', 2)).toBe(false); }); test('should be case insensitive', () => { expect(matcher.isSimilar('HELLO', 'hello')).toBe(true); }); }); describe('similarityScore', () => { test('should return 1.0 for identical strings', () => { const score = matcher.similarityScore('test', 'test'); expect(score).toBe(1.0); }); test('should return 1.0 for empty strings', () => { const score = matcher.similarityScore('', ''); expect(score).toBe(1.0); }); test('should return a score between 0 and 1', () => { const score = matcher.similarityScore('hello', 'hallo'); expect(score).toBeGreaterThan(0); expect(score).toBeLessThan(1); }); test('should be case insensitive', () => { const score1 = matcher.similarityScore('HELLO', 'hello'); const score2 = matcher.similarityScore('hello', 'hello'); expect(score1).toBe(score2); }); test('should give higher scores for closer matches', () => { const close = matcher.similarityScore('hello', 'helo'); const far = matcher.similarityScore('hello', 'xyz'); expect(close).toBeGreaterThan(far); }); }); describe('levenshteinDistance (via private method testing)', () => { test('should calculate distance for substitution', () => { // kitten → sitting: 3 substitutions const suggestions = matcher.findSuggestions('kitten', ['sitting']); expect(suggestions.length).toBe(0); // Distance 3 is too far with default threshold }); test('should calculate distance for insertion', () => { // cat → cats: 1 insertion const suggestions = matcher.findSuggestions('cat', ['cats']); expect(suggestions).toContain('cats'); }); test('should calculate distance for deletion', () => { // cats → cat: 1 deletion const suggestions = matcher.findSuggestions('cats', ['cat']); expect(suggestions).toContain('cat'); }); test('should handle short query strings', () => { // Single character query should still find matches const suggestions = matcher.findSuggestions('f', ['find', 'run', 'list']); // 'f' to 'find' has distance 3 (add i, n, d) // With threshold 1/3 of 'f'.length = 0, only exact matches (none) // So we don't expect results with default threshold expect(Array.isArray(suggestions)).toBe(true); }); }); describe('real-world command matching', () => { const ncpCommands = [ 'find', 'run', 'list', 'add', 'remove', 'config', 'auth', 'update', 'profile', 'doctor', 'help' ]; test('should handle common typos in commands', () => { const typos = { 'fnd': 'find', // distance 1 'lst': 'list', // distance 1 'cinfig': 'config', // distance 1 'doctro': 'doctor' // distance 1 }; Object.entries(typos).forEach(([typo, expected]) => { const suggestions = matcher.findSuggestions(typo, ncpCommands); expect(suggestions[0]).toBe(expected); }); }); test('should suggest alternatives for unknown commands', () => { const suggestions = matcher.findSuggestions('finde', ncpCommands); expect(suggestions.length).toBeGreaterThan(0); expect(suggestions).toContain('find'); }); }); });