mathjs/test/unit-tests/expression/node/RangeNode.test.js

// test RangeNode
import assert from 'assert'

import math from '../../../../src/defaultInstance.js'
const Node = math.Node
const ConstantNode = math.ConstantNode
const SymbolNode = math.SymbolNode
const RangeNode = math.RangeNode
const OperatorNode = math.OperatorNode

describe('RangeNode', function () {
  it('should create a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const n = new RangeNode(start, end)
    assert(n instanceof RangeNode)
    assert(n instanceof Node)
    assert.strictEqual(n.type, 'RangeNode')
  })

  it('should have isRangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const node = new RangeNode(start, end)

    assert(node.isRangeNode)
  })

  it('should throw an error when calling without new operator', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    assert.throws(function () { RangeNode([start, end]) }, SyntaxError)
  })

  it('should throw an error creating a RangeNode with wrong number or type of arguments', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)

    assert.throws(function () { console.log(new RangeNode()) }, TypeError)
    assert.throws(function () { console.log(new RangeNode(start)) }, TypeError)
    assert.throws(function () { console.log(new RangeNode([])) }, TypeError)
    assert.throws(function () { console.log(new RangeNode(start, end, start, end)) }, Error)
    assert.throws(function () { console.log(new RangeNode(0, 10)) }, TypeError)
  })

  it('should compile a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const expr = n.compile()
    assert.deepStrictEqual(expr.evaluate(), math.matrix([0, 2, 4, 6, 8, 10]))
  })

  it('should filter a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    assert.deepStrictEqual(n.filter(function (node) { return node instanceof RangeNode }), [n])
    assert.deepStrictEqual(n.filter(function (node) { return node instanceof SymbolNode }), [])
    assert.deepStrictEqual(n.filter(function (node) { return node instanceof ConstantNode }), [start, end, step])
    assert.deepStrictEqual(n.filter(function (node) { return node instanceof ConstantNode && node.value === 2 }), [step])
    assert.deepStrictEqual(n.filter(function (node) { return node instanceof ConstantNode && node.value === 4 }), [])
  })

  it('should run forEach on a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const nodes = []
    const paths = []
    n.forEach(function (node, path, parent) {
      nodes.push(node)
      paths.push(path)
      assert.strictEqual(parent, n)
    })

    assert.strictEqual(nodes.length, 3)
    assert.strictEqual(nodes[0], start)
    assert.strictEqual(nodes[1], end)
    assert.strictEqual(nodes[2], step)
    assert.deepStrictEqual(paths, ['start', 'end', 'step'])
  })

  it('should map a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const nodes = []
    const paths = []
    const e = new ConstantNode(3)
    const f = n.map(function (node, path, parent) {
      nodes.push(node)
      paths.push(path)
      assert.strictEqual(parent, n)

      return node instanceof ConstantNode && node.value === 0 ? e : node
    })

    assert.strictEqual(nodes.length, 3)
    assert.strictEqual(nodes[0], start)
    assert.strictEqual(nodes[1], end)
    assert.strictEqual(nodes[2], step)
    assert.deepStrictEqual(paths, ['start', 'end', 'step'])

    assert.notStrictEqual(f, n)
    assert.deepStrictEqual(f.start, e)
    assert.deepStrictEqual(f.end, end)
    assert.deepStrictEqual(f.step, step)
  })

  it('should throw an error when the map callback does not return a node', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    assert.throws(function () {
      n.map(function () {})
    }, /Callback function must return a Node/)
  })

  it('should transform a RangeNodes start', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const e = new ConstantNode(3)
    const f = n.transform(function (node) {
      return node instanceof ConstantNode && node.value === 0 ? e : node
    })

    assert.notStrictEqual(f, n)
    assert.deepStrictEqual(f.start, e)
    assert.deepStrictEqual(f.end, end)
    assert.deepStrictEqual(f.step, step)
  })

  it('should transform a RangeNodes end', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const e = new ConstantNode(3)
    const f = n.transform(function (node) {
      return node instanceof ConstantNode && node.value === 10 ? e : node
    })

    assert.notStrictEqual(f, n)
    assert.deepStrictEqual(f.start, start)
    assert.deepStrictEqual(f.end, e)
    assert.deepStrictEqual(f.step, step)
  })

  it('should transform a RangeNodes step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const e = new ConstantNode(3)
    const f = n.transform(function (node) {
      return node instanceof ConstantNode && node.value === 2 ? e : node
    })

    assert.notStrictEqual(f, n)
    assert.deepStrictEqual(f.start, start)
    assert.deepStrictEqual(f.end, end)
    assert.deepStrictEqual(f.step, e)
  })

  it('should transform a RangeNodes without step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const n = new RangeNode(start, end)

    const e = new ConstantNode(3)
    const f = n.transform(function (node) {
      return node instanceof ConstantNode && node.value === 10 ? e : node
    })

    assert.notStrictEqual(f, n)
    assert.deepStrictEqual(f.start, start)
    assert.deepStrictEqual(f.end, e)
  })

  it('should transform a RangeNode itself', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    const e = new ConstantNode(5)
    const f = n.transform(function (node) {
      return node instanceof RangeNode ? e : node
    })

    assert.deepStrictEqual(f, e)
  })

  it('should clone a RangeNode', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const c = new RangeNode(start, end, step)

    const d = c.clone()

    assert.deepStrictEqual(d, c)
    assert.notStrictEqual(d, c)
    assert.strictEqual(d.start, c.start)
    assert.strictEqual(d.end, c.end)
    assert.strictEqual(d.step, c.step)
  })

  it('should clone a RangeNode without step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const c = new RangeNode(start, end)

    const d = c.clone()

    assert(d instanceof RangeNode)
    assert.deepStrictEqual(d, c)
    assert.notStrictEqual(d, c)
    assert.strictEqual(d.start, c.start)
    assert.strictEqual(d.end, c.end)
    assert.strictEqual(d.step, c.step)
    assert.strictEqual(d.step, null)
  })

  it('test equality another Node', function () {
    assert.strictEqual(createRangeNode(2, 4).equals(createRangeNode(2, 4)), true)
    assert.strictEqual(createRangeNode(2, 4).equals(createRangeNode(2, 5)), false)
    assert.strictEqual(createRangeNode(2, 4).equals(createRangeNode(2, 4, 1)), false)
    assert.strictEqual(createRangeNode(2, 4).equals(createRangeNode(2, 4, -1)), false)
    assert.strictEqual(createRangeNode(2, 4, -1).equals(createRangeNode(2, 4, -1)), true)
    assert.strictEqual(createRangeNode(2, 4, -1).equals(null), false)
    assert.strictEqual(createRangeNode(2, 4, -1).equals(undefined), false)
    assert.strictEqual(createRangeNode(2, 4, -1).equals(new SymbolNode('a')), false)
    assert.strictEqual(createRangeNode(2, 4, -1).equals(new SymbolNode('a')), false)
  })

  it('should stringify a RangeNode without step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const n = new RangeNode(start, end)

    assert.strictEqual(n.toString(), '0:10')
  })

  it('should stringify a RangeNode with step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    assert.strictEqual(n.toString(), '0:2:10')
  })

  it('should stringify a RangeNode with an OperatorNode', function () {
    const a = new ConstantNode(1)
    const b = new ConstantNode(2)

    const o1 = new OperatorNode('+', 'add', [a, b])
    const o2 = new OperatorNode('<', 'smaller', [a, b])

    const n = new RangeNode(o1, o1, o2)

    assert.strictEqual(n.toString(), '1 + 2:(1 < 2):1 + 2')
  })

  it('should stringify a RangeNode with a RangeNode', function () {
    const start1 = new ConstantNode(0)
    const end1 = new ConstantNode(10)
    const step2 = new ConstantNode(2)
    const end2 = new ConstantNode(100)

    const start2 = new RangeNode(start1, end1)
    const n = new RangeNode(start2, end2, step2)

    assert.strictEqual(n.toString(), '(0:10):2:100')
  })

  it('should stringify a RangeNode with custom toString', function () {
    // Also checks if the custom functions get passed on to the children
    const customFunction = function (node, options) {
      if (node.type === 'RangeNode') {
        return 'from ' + node.start.toString(options) +
          ' to ' + node.end.toString(options) +
          ' with steps of ' + node.step.toString(options)
      } else if (node.type === 'ConstantNode') {
        return 'const(' + node.value + ', ' + math.typeOf(node.value) + ')'
      }
    }

    const a = new ConstantNode(1)
    const b = new ConstantNode(2)
    const c = new ConstantNode(3)

    const n = new RangeNode(a, b, c)

    assert.strictEqual(n.toString({ handler: customFunction }), 'from const(1, number) to const(2, number) with steps of const(3, number)')
  })

  it('should respect the \'all\' parenthesis option', function () {
    assert.strictEqual(math.parse('1:2:3').toString({ parenthesis: 'all' }), '(1):(2):(3)')
    assert.strictEqual(math.parse('1:2:3').toTex({ parenthesis: 'all' }), '\\left(1\\right):\\left(2\\right):\\left(3\\right)')
  })

  it('toJSON and fromJSON', function () {
    const a = new ConstantNode(0)
    const b = new ConstantNode(10)
    const c = new ConstantNode(2)
    const node = new RangeNode(a, b, c)

    const json = node.toJSON()

    assert.deepStrictEqual(json, {
      mathjs: 'RangeNode',
      start: a,
      end: b,
      step: c
    })

    const parsed = RangeNode.fromJSON(json)
    assert.deepStrictEqual(parsed, node)
  })

  it('should LaTeX a RangeNode without step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const n = new RangeNode(start, end)

    assert.strictEqual(n.toTex(), '0:10')
  })

  it('should LaTeX a RangeNode with step', function () {
    const start = new ConstantNode(0)
    const end = new ConstantNode(10)
    const step = new ConstantNode(2)
    const n = new RangeNode(start, end, step)

    assert.strictEqual(n.toTex(), '0:2:10')
  })

  it('should LaTeX a RangeNode with custom toTex', function () {
    // Also checks if the custom functions get passed on to the children
    const customFunction = function (node, options) {
      if (node.type === 'RangeNode') {
        return 'from ' + node.start.toTex(options) +
          ' to ' + node.end.toTex(options) +
          ' with steps of ' + node.step.toTex(options)
      } else if (node.type === 'ConstantNode') {
        return 'const\\left(' + node.value + ', ' + math.typeOf(node.value) + '\\right)'
      }
    }

    const a = new ConstantNode(1)
    const b = new ConstantNode(2)
    const c = new ConstantNode(3)

    const n = new RangeNode(a, b, c)

    assert.strictEqual(n.toTex({ handler: customFunction }), 'from const\\left(1, number\\right) to const\\left(2, number\\right) with steps of const\\left(3, number\\right)')
  })

  /**
   * Helper function to create a RangeNode
   * @param {number} start
   * @param {number} end
   * @param {number} [step]
   * @return {RangeNode}
   */
  function createRangeNode (start, end, step) {
    if (step === undefined) {
      return new RangeNode(new ConstantNode(start), new ConstantNode(end))
    } else {
      return new RangeNode(new ConstantNode(start), new ConstantNode(end), new ConstantNode(step))
    }
  }
})