2 Commits

Author	SHA1	Message	Date
Tom Boucher	2972da4c9d	enhance(#3619): ratchet the platform seam with local/no-private-binary-resolution (epic #3411 Phase 3) (#3636) ... * chore(#3619): ratchet the platform seam with local/no-private-binary-resolution Epic #3411 Phase 3, the ratchet. Scope revised with maintainer approval and recorded on the issue: the epic's literal ask was a rule rejecting a bare-name spawn outside the seam. Surveyed at ac1b6d679, ~30 such sites exist and none is a defect — git, gh and npm ship native .exe that CreateProcess resolves unaided, and the rest are POSIX-only tools. ADR-1703 rules 2 and 3 forbid grandfathering and escape hatches, so a literal rule would be unsuppressable and would force rewriting 30 correct calls. The epic's actual thesis was four private RESOLVERS, not four bare spawns. So the rule flags re-implementing resolution: reading PATHEXT in any casing from any object, and a hardcoded list carrying two or more of .exe/.cmd/.bat/.com — precisely the shapes fallow-runner's candidateNames and gsd-tools' PATHEXT string had before Phases 1 and 2 deleted them. Three boundaries were arrived at rather than assumed: two-or-more a single .endsWith('.cmd') is a classification, not a candidate set; runtime-hooks-surface derives .cmd shim paths that way boundary-aware a naive substring test flags .execute and .compacting, caught on src/host-integration.cts before it could become a false positive nobody could suppress suffix-anchored the seam exemption matches src/shell-command-projection.cts exactly; a substring match would also exempt the dispatch test file. Case I9 pins it. PATH scans are deliberately NOT flagged — membership checks (bin/install.js) are indistinguishable from resolution scans, and an unsound rule in a zero-escape-hatch architecture is worse than no rule. To make the ratchet strict with no carve-out, resolveExecutableBinary gained pathOverride: search THIS PATH, read everything else including PATHEXT from the ambient environment. resolveFallowBinary now supplies its own search path without hand-threading PATHEXT, which would itself have been a private read. The three alternatives were all worse: exempting the file is grandfathering, exempting the AST shape is a carve-out every future caller must replicate, and dropping the pass-through would silently ignore a user's real PATHEXT — buying a lint rule with a correctness regression. eslint-rules/** is outside the rule's globs rather than exempted, because portability-vocab.cjs owns the extension set. scripts/**/*.cjs got its own block so that exclusion does not leave a hole in the ratchet. Started green with nothing suppressed. Proven able to fail: a fixture with both signals reports two errors. Refs #3411 * fix(#3619): close the PATHEXT destructuring evasion and correct two overclaims Adversarial review found a trivial evasion of the rule's primary signal: the visitor only handled MemberExpression, so const { PATHEXT } = process.env const { PATHEXT: exts } = process.env const { Pathext } = opts.env were all unflagged. That is a common idiom, not an exotic bypass. An ObjectPattern visitor now catches it in every form — renamed, any casing, any receiver, string keys — while leaving a computed key alone, since it is not statically decidable. I10-I13 pin the invalid forms and V9/V10 pin PATH and the computed key. Two overclaims corrected, both mine: Standards review proved the docs were factually wrong. Both the ADR amendment and the CONTEXT.md entry asserted that tests/shell-command-projection-dispatch.test.cjs is still linted by this rule. It is not — the rule's surface is src, gsd-core/bin, scripts and hooks, and tests/** is deliberately outside it because test setup legitimately assigns process.env.PATHEXT (fallow-runner's P3 does exactly that). The suffix-vs-substring distinction is therefore proven by RuleTester case I9 feeding a synthetic filename, NOT by real coverage of that file. Both documents now say so. The rule's own docstring claimed the seam exemption matches the seam path 'exactly'. It is a suffix match, so a nested foo/src/shell-command-projection.cts would also be exempt. Suffix matching is kept — it is how sibling rules resolve paths and the nested case does not exist — but the docstring now states the boundary rather than overstating the precision. The evasion fix was verified by executing eslint against both destructuring forms in scripts/, not by inspection. Probe: 31/31. Refs #3411 * chore(#3619): backfill changeset pr number 3636 --------- Co-authored-by: sim <sim@local>	2026-08-18 16:40:17 -04:00
Tom Boucher	ac1b6d679f	enhance(#3618): fold fallow-runner onto the canonical binary resolver (epic #3411 Phase 2) (#3633) ... * chore(#3618): fold fallow-runner onto the canonical binary resolver Epic #3411 Phase 2. src/fallow-runner.cts was the fourth divergent implementation of Windows binary resolution the epic enumerated — candidateNames, isExecutableFile, findInPath, findInNodeModules, 40 lines. All four are deleted; resolveFallowBinary is one seam call. Two OPT-IN options were added to resolveExecutableBinary to make the fold behavior-preserving, both defaulting off so Phase 1's callers are byte-identical: prependPaths dirs searched before env.PATH, in order, through the identical per-directory candidate logic. This expresses node_modules/.bin-first precedence without env surgery — the rejected alternative re-introduced the spread-loses-the-proxy hazard the Windows lane caught in Phase 1, at every future call site instead of once. requireExecutable POSIX-only accessSync(X_OK); a no-op on win32 where mode bits do not mean execute. Opt-in rather than default because unconditional X_OK breaks #3445's suite, which stages candidates with plain writeFileSync and never sets an exec bit — the repo bans chmod in tests — so every one would resolve to null on POSIX. Deliberate behavior change on Windows: fallow's prior candidate list ended in a BARE fallow. The seam never tries a bare name there, so an extensionless file beside fallow.cmd is no longer resolved. That is the fix, not a regression — the extensionless file is npm's POSIX sh shim, which CreateProcess cannot run (#3275). Rows 7 and 8 of the design record it. Defect found while working, fixed inline: the resolution order was documented BACKWARDS as PATH-then-.bin in structural-pre-pass.md, docs/INVENTORY.md and four INVENTORY translations. The code has always been .bin first, and .bin first is correct — a project-local tool should beat a global one. The archived changeset is left alone as a historical record. fallow-runner had no test file at all. tests/fallow-runner.test.cjs is new (F1-F15) and the seam options are pinned by S1-S12 folded into the existing dispatch suite. RED proven by execution: with both source files stashed and build:lib re-run, 7 of 27 probe cases failed. Refs #3411 * chore(#3618): backfill changeset pr number 3633 * fix(#3618): assert both platform contracts in F4 instead of a POSIX-only premise Windows CI on #3633 failed F4. The test monkeypatched accessSync to throw and asserted resolveFallowBinary returned null — but that premise, that the X_OK check is consulted at all, is POSIX-only by design. requireExecutable is a deliberate no-op on win32 because Windows mode bits do not mean execute, so the staged fixture correctly resolved there. 40-design.md's negative-space section already states this carve-out verbatim. The test contradicted the design it was written from: fixtures were made platform-adaptive in the previous commit, and this assertion was left platform-blind. F4 now asserts BOTH contracts — null on POSIX, resolves on win32 — rather than skipping either. A t.skip on one lane would have been green and would have left the win32 carve-out unpinned by fallow's own entry point. Audited every other row for the same class. F1-F3, F5, F6, F11-F15 hold on both platforms; F7-F10 and S1-S12 inject platform explicitly and are unaffected. F4 was the only row with a single-platform premise. The local probe runs on one platform and structurally cannot catch this, which is why it was green — that limitation is now stated at the top of the probe so a green probe is not mistaken for platform coverage. The win32 branch was proven by injecting platform:'win32' with accessSync throwing and asserting it still resolves. Refs #3411 --------- Co-authored-by: sim <sim@local>	2026-08-18 15:32:57 -04:00