[Certora] SumOfCredits equals TotalUnits plus Fees. - #1063
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This is the main solvency invariant: the totalUnits equals the correctly scaled sums of all position credit plus fee. Together with the invariant from Midnight.spec that totalUnits equals the sum of all debts plus the withdrawable amount, this shows that all credits are backed by debt.
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Sounds great !
Didn't have the time to look at the proof in depth, nor to look at the other UpdatePositionView spec
Also instead of requiring some axioms for all values, we require the axioms in summaryMulDivDown only for the used values.
Co-authored-by: Quentin Garchery <garchery.quentin@gmail.com> Signed-off-by: Jochen Hoenicke <hoenicke@gmail.com>
Rename cvl*Of functions. Use invariant from Midnight.spec
Made the specs more similar to each other (adapted variable names). Use "proved in UpdatePositionView" as explanation for require.
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This is the main solvency invariant: the totalUnits equals the correctly scaled sums of all position credit plus fee. Together with the invariant from Midnight.spec that totalUnits equals the sum of all debts plus the withdrawable amount, this shows that all credits are backed by debt.
This pull-request superseeds #534.
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