fix: escape regex metacharacters in Q.like (LokiJS adapter diverges from SQLite)

src/utils/fp/likeToRegexp/index.js

@@ -1,6 +1,10 @@
 // @flow
 
 export default function likeToRegexp(likeQuery: string): RegExp {
-  const regexp = `^${likeQuery}$`.replace(/%/g, '.*').replace(/_/g, '.')
+  // Escape regex special characters so the pattern is matched literally — the
+  // same way the SQLite adapter treats a LIKE pattern. `%` and `_` are
+  // intentionally not escaped here so they remain LIKE wildcards below.
+  const escaped = likeQuery.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')
+  const regexp = `^${escaped}$`.replace(/%/g, '.*').replace(/_/g, '.')
   return new RegExp(regexp, 'is')
 }

src/utils/fp/likeToRegexp/test.js

@@ -0,0 +1,33 @@
+import likeToRegexp from './index'
+
+describe('likeToRegexp', () => {
+  it('treats % and _ as wildcards', () => {
+    expect(likeToRegexp('100%').test('100abc')).toBe(true)
+    expect(likeToRegexp('a_b').test('axb')).toBe(true)
+    expect(likeToRegexp('a_b').test('ab')).toBe(false)
+  })
+
+  it('matches newlines (dotall) and is case-insensitive', () => {
+    expect(likeToRegexp('a%b').test('a\nb')).toBe(true)
+    expect(likeToRegexp('a_b').test('a\nb')).toBe(true)
+    expect(likeToRegexp('ABC').test('abc')).toBe(true)
+  })
+
+  it('treats regex special characters as literals (matching the SQLite adapter)', () => {
+    // `.` is a literal dot, not "any character"
+    expect(likeToRegexp('a.b').test('a.b')).toBe(true)
+    expect(likeToRegexp('a.b').test('axb')).toBe(false)
+    expect(likeToRegexp('%.pdf').test('doc.pdf')).toBe(true)
+    expect(likeToRegexp('%.pdf').test('docXpdf')).toBe(false)
+    // `+` is a literal, not a quantifier
+    expect(likeToRegexp('c+').test('c+')).toBe(true)
+    expect(likeToRegexp('c+').test('cccc')).toBe(false)
+  })
+
+  it('does not crash on unbalanced regex metacharacters', () => {
+    expect(() => likeToRegexp('a(b')).not.toThrow()
+    expect(likeToRegexp('a(b').test('a(b')).toBe(true)
+    expect(() => likeToRegexp('a[b')).not.toThrow()
+    expect(likeToRegexp('a[b').test('a[b')).toBe(true)
+  })
+})