Prove AbsoluteMin#1
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Adds a plain @BmcProof asserting AbsoluteMin.getMinValue's documented contract: the result must be the input element closest to zero. It REFUTES with the two-element witness getMinValue(-3, -2) == -3 (should be -2, since |-2| < |-3|). The bug: the filter keeps abs-<= candidates but then takes the arithmetic Math.min, so the more-negative element wins. CI goes red and the proof-report comment shows the counterexample row.
bmc4j proof results
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The defect is specifically that, among two negatives, getMinValue keeps the more-negative (larger-magnitude) value instead of the one closest to zero. Constraining both symbolic inputs to be negative makes the refutation witness land in that regime, matching the documented counterexample.
Reverts the negative-only pinning: keep both inputs symbolic over [-3, 3] so the proof asserts the contract across positives and negatives alike. The refutation witness the engine emits is reported faithfully in the PR comment.
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maths/AbsoluteMin.getMinValue(int...)is documented to return the element with the smallest absolute value (the upstreamAbsoluteMinTestassertsgetMinValue(3, -10, -2) == -2). It doesn't.This PR adds one plain
@BmcProofasserting that contract over symbolic inputs:|result|must equal the minimum absolute value among the inputs. It REFUTES.Counterexample
getMinValue(-3, -2)returns-3, but|-2| < |-3|, so the contract requires-2.Witness:
a = -3, b = -2, r = -3, minAbs = 2.Root cause
After filtering to the abs-≤ candidates, the code updates the running winner with
Math.min(value, number)— the arithmetic minimum — instead of the candidate itself. Between two negatives that keeps the more negative (larger-magnitude) value.CI is therefore red on purpose: the asserted contract genuinely refutes, and the proof-results comment below shows the
❌ REFUTEDrow with the counterexample. That red check + the witness is the shareable artifact. Left open as the showcase; upstream is untouched.