test(divergence): flip load-toplevel-echo to a hard agreement (#40)#16
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…n-lua#40) Bifrost surfaced a real divergence found while running a Shen spec across shen-rust/shen-go/shen-lua: the canonical kernel load (klambda/load.kl shen.eval-and-print) prints each toplevel form's value before returning `loaded`. shen-rust and shen-go do; shen-lua does on a cold fasl cache / SHEN_FASL=off but DROPS the echo on a warm fasl-cache hit (documented degrade, boot.lua ~796). So (load file) stdout is cache-state dependent -- a cross-port divergence and an intra-port nondeterminism. - programs/load-echo-probe.shen: minimal probe ("PROBE" / (+ 40 2) / (define p)) - cases/divergences.json: load-toplevel-echo, mode eval, expect agreement + known_divergence shen-lua-fasl-load-echo (reports DIVERGE, not FAIL, until it converges -- then drop the marker for a hard agreement, as hush-file-write did) Verified: bifrost --only load-toplevel-echo across shen-rust,shen-go,shen-lua reports KNOWN DIVERGENCE: '"PROBE"\n42\n\nloaded' <- shen-go,shen-rust vs 'loaded' <- shen-lua. Filed pyrex41/shen-lua#40 with root cause + fix options. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
shen-lua's warm-fasl `(load)` echo divergence is fixed (pyrex41/shen-lua#40, PR #41): a warm cache hit now re-emits each top-level form's value, so `(load FILE)` stdout no longer depends on cache state and agrees with shen-rust/ shen-go cold and warm. Drop the `known_divergence` marker so the case is now a HARD agreement (a real FAIL if any port regresses), mirroring the lifecycle hush-file-write went through. Doc updated to RESOLVED with the PR ref. Also complete the run-time banner strip in normalize(): the kernel banner is `(cn "\nrun time: " ...)`, whose leading newline leaves a BLANK line ahead of the text line. We stripped only the text, so the residual blank diverged against a port that omits the whole banner (shen-lua on a warm hit re-emits the value echo but not the cosmetic banner). Drop that blank too, so the entire cosmetic banner is normalized away symmetrically across ports. README: refresh the divergence status (load-toplevel-echo now resolved; the list is all hard agreements) and a light intro trim. Verified: full corpus 31 pass / 0 diverge / 0 FAIL across shen-rust, shen-go, shen-lua, on both warm and cold shen-lua fasl caches. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Companion to pyrex41/shen-lua#41 (fixes pyrex41/shen-lua#40).
What
shen-lua's warm-fasl(load)echo divergence is fixed: a warm cache hit now re-emits each top-level form's value, so(load FILE)stdout no longer depends on cache state and agrees with shen-rust / shen-go on both cold and warm caches.known_divergence: shen-lua-fasl-load-echofromload-toplevel-echo, so a disagreement is now a real FAIL rather than a documented DIVERGE — the same lifecyclehush-file-writewent through. Doc updated to RESOLVED with the PR ref.normalize(). The kernel banner is(cn "\nrun time: " ...); its leading newline leaves a blank line ahead of the text line. We stripped only the text, leaving the blank as residue — which diverged against a port that omits the whole banner (shen-lua on a warm hit re-emits the value echo but not the cosmetic banner). Now the blank preceding a strippedrun time:line is dropped too, so the entire cosmetic banner normalizes away symmetrically across ports. (Harmless for ports that emit the banner — the strip is symmetric.)load-toplevel-echonow resolved; the list is all hard agreements) + a light intro trim.The first commit (
test(divergence): add load-toplevel-echo cross-port case) is the tracking case; it was authored on a sibling branch and is cherry-picked here so this PR is self-contained againstmain.Verification
Full corpus 31 pass / 0 diverge / 0 FAIL across shen-rust, shen-go, shen-lua — on both a warm and a cold shen-lua fasl cache:
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