Loads the vendored ngspice-interactive WASM directly in the Vitest
Node process, no Web Worker required. Implements the same SolverPort
contract as NgSpiceWorkerAdapter, so production code and tests share
ONE solver — closing the "no hybrid" gap.
loadNgSpiceForNode (Node-only loader):
- Reads ngspice-lib.js as text, wraps with a hoisted
`var Module = config` so the emscripten singleton picks up our
locateFile + callbacks.
- Re-wires Module.onRuntimeInitialized to copy closure-local FS /
HEAP* into Module._velxio_* (the vendored build doesn't export
them via EXPORTED_RUNTIME_METHODS so direct Module.FS triggers an
abort accessor).
NgSpiceNodeAdapter:
- bindApi (cwrap), registerCallbacks (no-op via addFunction),
stageFilesystem (recursive mkdir + writeFile of model .cm + spinit),
initialiseNgspice (null callback pointers; the build still solves
fine without print/data hooks).
- loadCircuit writes the netlist to /circuit.spc on the FS and
issues `source /circuit.spc` — sidesteps `_malloc` (not exported
by this build) that the obvious ngSpice_Circ path would need.
- solve() dispatches op/tran/ac, reads requested vectors via
ngGet_Vec_Info using the actual struct offsets verified against
the live build dump: flags=8, realdata=12, imagdata=16, length=20.
- alterSource issues `alter` for incremental re-solves.
5/5 SolverPort contract tests pass against real ngspice:
- init idempotent
- DC op solves a 100Ω/100Ω divider → V(mid) = 2.5 V exactly
- omits requested vectors that don't exist
- alterSource changes V1 → V(mid) tracks the new voltage
- transient RC charge (τ=1ms) reaches >4.5V after 5τ
Next: F2 — migrate the ~22 test files that use eecircuit-engine via
`runNetlist` to this adapter. After F2, F3 deletes eecircuit-engine
and `SpiceEngine.ts` for good.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>