You said Packer was not a Calvinist and Packer showed that he was a Calvinist. That confirms something alright.
I will give you this: From perusing Packers book, he is generally positive and encouraging as opposed to the doom and gloom Calvin - see below:
“thieves and murderers, and other evildoers, are instruments of divine providence, being employed by the Lord himself to execute judgments which he has resolved to inflict.” (John Calvin, Institutes of Christian Religion, Book 1, Chapter 17, Paragraph 5)
“The devil, and the whole train of the ungodly, are in all directions, held in by the hand of God as with a bridle, so that they can neither conceive any mischief, nor plan what they have conceived, nor how muchsoever they may have planned, move a single finger to perpetrate, unless in so far as he permits, nay unless in so far as he commands, that they are not only bound by his fetters but are even forced to do him service” (John Calvin, Institutes of Christian Religion, Book 1, Chapter 17, Paragraph 11)
“…salvation is freely offered to some while others are barred from access to it.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 21, Paragraph 5)
“…we say that God once established by his eternal and unchangeable plan those whom he long before determined once for all to receive into salvation, and those whom, on the other hand, he would devote to destruction…he has barred the door of life to those whom he has given over to damnation.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 21, Paragraph 7)
“We cannot assign any reason for his bestowing mercy on his people, but just as it so pleases him, neither can we have any reason for his reprobating others but his will.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 22, Paragraph 11)
“Therefore, those whom God passes over, he condemns; and this he does for no other reason than that he wills to exclude them from the inheritance which he predestines for his own children.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 1)
“…individuals are born, who are doomed from the womb to certain death, and are to glorify him by their destruction.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 6)
“…it is very wicked merely to investigate the causes of God’s will. For his will is, and rightly ought to be, the cause of all things that are.”…”For God’s will is so much the highest rule of righteousness that whatever he wills, by the very fact that he wills it, must be considered righteous. When, therefore, one asks why God has so done, we must reply: because he has willed it. But if you proceed further to ask why he so willed, you are seeking something greater and higher than God’s will, which cannot be found.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 1)
“I admit that in this miserable condition wherein men are now bound, all of Adam’s children have fallen by God’s will.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 4)
“Again I ask: whence does it happen that Adam’s fall irremediably involved so many peoples, together with their infant offspring, in eternal death unless because it so pleased God? The decree is dreadful indeed, I confess. Yet no one can deny that God foreknew what end man was to have before he created him, and consequently foreknew because he so ordained by his decree. And it ought not to seem absurd for me to say that God not only foresaw the fall of the first man, and in him the ruin of his descendants, but also meted it out in accordance with his own decision.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 7)
“For if predestination is nothing but the meting out of divine justice–secret, indeed, but blameless–because it is certain that they were not unworthy to be predestined to this condition, it is equally certain that the destruction they undergo by predestination is also most just. Besides, their perdition depends upon the predestination of God in such a way that the cause and occasion of it are found in themselves. For the first man fell because the Lord had judged it to be expedient; why he so judged is hidden from us.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 8)
“Man falls according as God’s providence ordains, but he falls by his own fault.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 23, Paragraph 8)
“Moreover, the wicked bring upon themselves the just destruction to which they are destined.” (John Calvin, Institutes of Christian Religion, Book 3, Chapter 24, heading)