yjs/src/Databases/RedBlackTree.spec.js

/* eslint-env browser,jasmine,console */
'use strict'

var Y = require('../SpecHelper.js')
var numberOfRBTreeTests = 1000

function itRedNodesDoNotHaveBlackChildren () {
  it('Red nodes do not have black children', function () {
    function traverse (n) {
      if (n == null) {
        return
      }
      if (n.isRed()) {
        if (n.left != null) {
          expect(n.left.isRed()).not.toBeTruthy()
        }
        if (n.right != null) {
          expect(n.right.isRed()).not.toBeTruthy()
        }
      }
      traverse(n.left)
      traverse(n.right)
    }
    traverse(this.tree.root)
  })
}

function itBlackHeightOfSubTreesAreEqual () {
  it('Black-height of sub-trees are equal', function () {
    function traverse (n) {
      if (n == null) {
        return 0
      }
      var sub1 = traverse(n.left)
      var sub2 = traverse(n.right)
      expect(sub1).toEqual(sub2)
      if (n.isRed()) {
        return sub1
      } else {
        return sub1 + 1
      }
    }
    traverse(this.tree.root)
  })
}

function itRootNodeIsBlack () {
  it('root node is black', function () {
    expect(this.tree.root == null || this.tree.root.isBlack()).toBeTruthy()
  })
}

describe('RedBlack Tree', function () {
  var tree, memory
  describe('debug #2', function () {
    beforeAll(function (done) {
      this.memory = new Y.Memory(null, {
        name: 'Memory',
        gcTimeout: -1
      })
      this.tree = this.memory.os
      tree = this.tree
      memory = this.memory
      memory.requestTransaction(function * () {
        yield* tree.put({id: [8433]})
        yield* tree.put({id: [12844]})
        yield* tree.put({id: [1795]})
        yield* tree.put({id: [30302]})
        yield* tree.put({id: [64287]})
        yield* tree.delete([8433])
        yield* tree.put({id: [28996]})
        yield* tree.delete([64287])
        yield* tree.put({id: [22721]})
        done()
      })
    })

    itRootNodeIsBlack()
    itBlackHeightOfSubTreesAreEqual([])
  })

  describe(`After adding&deleting (0.8/0.2) ${numberOfRBTreeTests} times`, function () {
    var elements = []
    beforeAll(function (done) {
      this.memory = new Y.Memory(null, {
        name: 'Memory',
        gcTimeout: -1
      })
      this.tree = this.memory.os
      tree = this.tree
      memory = this.memory
      memory.requestTransaction(function * () {
        for (var i = 0; i < numberOfRBTreeTests; i++) {
          var r = Math.random()
          if (r < 0.8) {
            var obj = [Math.floor(Math.random() * numberOfRBTreeTests * 10000)]
            if (!tree.findNode(obj)) {
              elements.push(obj)
              yield* tree.put({id: obj})
            }
          } else if (elements.length > 0) {
            var elemid = Math.floor(Math.random() * elements.length)
            var elem = elements[elemid]
            elements = elements.filter(function (e) {
              return !Y.utils.compareIds(e, elem)
            })
            yield* tree.delete(elem)
          }
        }
        done()
      })
    })

    itRootNodeIsBlack()

    it('can find every object', function (done) {
      memory.requestTransaction(function * () {
        for (var id of elements) {
          expect((yield* tree.find(id)).id).toEqual(id)
        }
        done()
      })
    })

    it('can find every object with lower bound search', function (done) {
      this.memory.requestTransaction(function * () {
        for (var id of elements) {
          expect((yield* tree.findWithLowerBound(id)).id).toEqual(id)
        }
        done()
      })
    })
    itRedNodesDoNotHaveBlackChildren()

    itBlackHeightOfSubTreesAreEqual()

    it('iterating over a tree with lower bound yields the right amount of results', function (done) {
      var lowerBound = elements[Math.floor(Math.random() * elements.length)]
      var expectedResults = elements.filter(function (e, pos) {
        return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) && elements.indexOf(e) === pos
      }).length

      var actualResults = 0
      this.memory.requestTransaction(function * () {
        yield* tree.iterate(this, lowerBound, null, function * (val) {
          expect(val).toBeDefined()
          actualResults++
        })
        expect(expectedResults).toEqual(actualResults)
        done()
      })
    })

    it('iterating over a tree without bounds yield the right amount of results', function (done) {
      var lowerBound = null
      var expectedResults = elements.filter(function (e, pos) {
        return elements.indexOf(e) === pos
      }).length
      var actualResults = 0
      this.memory.requestTransaction(function * () {
        yield* tree.iterate(this, lowerBound, null, function * (val) {
          expect(val).toBeDefined()
          actualResults++
        })
        expect(expectedResults).toEqual(actualResults)
        done()
      })
    })

    it('iterating over a tree with upper bound yields the right amount of results', function (done) {
      var upperBound = elements[Math.floor(Math.random() * elements.length)]
      var expectedResults = elements.filter(function (e, pos) {
        return (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
      }).length

      var actualResults = 0
      this.memory.requestTransaction(function * () {
        yield* tree.iterate(this, null, upperBound, function * (val) {
          expect(val).toBeDefined()
          actualResults++
        })
        expect(expectedResults).toEqual(actualResults)
        done()
      })
    })

    it('iterating over a tree with upper and lower bounds yield the right amount of results', function (done) {
      var b1 = elements[Math.floor(Math.random() * elements.length)]
      var b2 = elements[Math.floor(Math.random() * elements.length)]
      var upperBound, lowerBound
      if (Y.utils.smaller(b1, b2)) {
        lowerBound = b1
        upperBound = b2
      } else {
        lowerBound = b2
        upperBound = b1
      }
      var expectedResults = elements.filter(function (e, pos) {
        return (Y.utils.smaller(lowerBound, e) || Y.utils.compareIds(e, lowerBound)) &&
          (Y.utils.smaller(e, upperBound) || Y.utils.compareIds(e, upperBound)) && elements.indexOf(e) === pos
      }).length
      var actualResults = 0
      this.memory.requestTransaction(function * () {
        yield* tree.iterate(this, lowerBound, upperBound, function * (val) {
          expect(val).toBeDefined()
          actualResults++
        })
        expect(expectedResults).toEqual(actualResults)
        done()
      })
    })
  })
})