[UnitTests] Add genderFilter tests

services/frontend/tests/unit/filters/gender.test.ts

@@ -0,0 +1,39 @@
+import { assert, describe, it } from 'vitest'
+
+import { genderFilter } from '@/components/FilterView/filters/gender'
+import { FormattedStudent } from '@oodikone/shared/types/studentData'
+
+import { createStudent } from './helpers'
+import { GenderCode } from '@oodikone/shared/types'
+
+const filterStudent = (student: FormattedStudent, selected: string) =>
+  genderFilter().filter(student, {
+    args: undefined,
+    options: { selected: parseInt(selected) },
+    precomputed: undefined,
+  })
+
+void describe('genderFilter', () => {
+  void it('should keep a student whose gender code matches the selected value', () => {
+    const student = createStudent({ gender_code: GenderCode.FEMALE })
+
+    assert.strictEqual(filterStudent(student, GenderCode.FEMALE), true)
+  })
+
+  void it('should exclude a student whose gender code does not match the selected value', () => {
+    const student = createStudent({ gender_code: GenderCode.MALE })
+
+    assert.strictEqual(filterStudent(student, GenderCode.FEMALE), false)
+  })
+
+  void it('should keep a student with an unknown gender code when unknown is selected', () => {
+    const student = createStudent({ gender_code: GenderCode.UNKNOWN })
+
+    assert.strictEqual(filterStudent(student, GenderCode.UNKNOWN), true)
+  })
+
+  void it('isActive should match the filter state', () => {
+    assert.strictEqual(genderFilter().isActive({ selected: '' }, undefined), false)
+    assert.strictEqual(genderFilter().isActive({ selected: GenderCode.MALE }, undefined), true)
+  })
+})