Maya bug report: MAnimCurveChange for an MFnAnimCurve.setTime does not work after undoing/redoing an addKeys

MAnimCurveChange_bug.py

# test AnimCurve.setTime undo/redo - api only

import maya.OpenMaya as om
import maya.OpenMayaAnim as oma

import maya.cmds as cmds

cmds.file(new=1, f=1)
curve = cmds.createNode('animCurveTL')

sel = om.MSelectionList()
sel.add(curve)
curveObj = om.MObject()
sel.getDependNode(0, curveObj)
mfnCurve = oma.MFnAnimCurve(curveObj)

origTimes = [0, 10, 20, 30, 40]
origVals = [0, 1, 2, 3, 4]
timeUnit = om.MTime.uiUnit()
mTimes = om.MTimeArray()
for t in origTimes:
    mTimes.append(om.MTime(t, timeUnit))
mVals = om.MDoubleArray()
for v in origVals:
    mVals.append(v)
linear = oma.MFnAnimCurve.kTangentLinear

# add keys

addKeysChange = oma.MAnimCurveChange()
mfnCurve.addKeys(mTimes, mVals, linear, linear, False, addKeysChange)

assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(10, timeUnit)
assert mfnCurve.value(1) == 1

# check that addKeysChange undo/redo works by itself
addKeysChange.undoIt()
assert mfnCurve.numKeys() == 0
addKeysChange.redoIt()
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(10, timeUnit)

# retime key index=1
retimeChange = oma.MAnimCurveChange()
mfnCurve.setTime(1, om.MTime(8, timeUnit), retimeChange)
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(8, timeUnit)

# check that retimeChange undo/redo works by itself
retimeChange.undoIt()
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(10, timeUnit)
retimeChange.redoIt()
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(8, timeUnit)

# check that we can undo + redo both changes
retimeChange.undoIt()
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(10, timeUnit)

addKeysChange.undoIt()
assert mfnCurve.numKeys() == 0

addKeysChange.redoIt()
assert mfnCurve.numKeys() == 5
assert mfnCurve.time(1) == om.MTime(10, timeUnit)

retimeChange.redoIt()
assert mfnCurve.numKeys() == 5
# redoing, after undoing/redoing the addKeys, doesn't work!
assert mfnCurve.time(1) == om.MTime(8, timeUnit)