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import { assoc } from './assoc.js'import { lens } from './lens.js'import { lensIndex } from './lensIndex.js'import { lensPath } from './lensPath.js'import { over } from './over.js'import { prop } from './prop.js'import { toUpper } from './toUpper.js'
const testObject = {  foo : 'bar',  baz : {    a : 'x',    b : 'y',  },}
test('assoc lens', () => {  const assocLens = lens(prop('foo'), assoc('foo'))  const result = over(    assocLens, toUpper, testObject  )  const expected = {    ...testObject,    foo : 'BAR',  }  expect(result).toEqual(expected)})
test('path lens', () => {  const pathLens = lensPath('baz.a')  const result = over(    pathLens, toUpper, testObject  )  const expected = {    ...testObject,    baz : {      a : 'X',      b : 'y',    },  }  expect(result).toEqual(expected)})
test('index lens', () => {  const indexLens = lensIndex(0)  const result = over(indexLens, toUpper)([ 'foo', 'bar' ])  expect(result).toEqual([ 'FOO', 'bar' ])})