Reproduction
Force midpoint Newton exhaustion or a nonzero LAPACK solve status in a symplectic step and inspect the returned status and accepted state.
Expected
Every nonlinear and linear-solve failure returns a named nonzero status and restores the accepted integrator and field state.
Actual
Some midpoint, Gauss, and Lobatto exits can fall through as success or expose partially mutated trial state. Failure counters therefore under-report the solver actually used by production modes.
Environment
SIMPLE main before PR #457.
Evidence
PR #457 propagates explicit statuses, fixes the Lobatto radial-stage index, and adds forced-failure behavioral tests without changing successful-step equations or convergence criteria.
Reproduction
Force midpoint Newton exhaustion or a nonzero LAPACK solve status in a symplectic step and inspect the returned status and accepted state.
Expected
Every nonlinear and linear-solve failure returns a named nonzero status and restores the accepted integrator and field state.
Actual
Some midpoint, Gauss, and Lobatto exits can fall through as success or expose partially mutated trial state. Failure counters therefore under-report the solver actually used by production modes.
Environment
SIMPLE
mainbefore PR #457.Evidence
PR #457 propagates explicit statuses, fixes the Lobatto radial-stage index, and adds forced-failure behavioral tests without changing successful-step equations or convergence criteria.