#Working on jvc

#Tests

Every module has a co-located *_test.j white-box overlay. jennifer test x_test.j splices x.j in first, so the overlay reaches the module's own names bare and its imports through their aliases.

jennifer test src/resolver_test.j                          # one module
jennifer test --filter=testDiamondUnifiesShared src/resolver_test.j
for t in src/*_test.j; do jennifer test "$t"; done         # everything
jennifer lint src/*.j bin/jvc                              # zero warnings

Glob the overlays rather than listing them, so a new module cannot be added without its tests running.

Two properties the suite depends on and that are easy to break:

• It is hermetic. No network, no credentials, nothing outside a temp directory. That is what lets the interpreter's own release pipeline run it against a release candidate.
• It needs the real git binary for app_test.j and gitsource_test.j, which build fixture repositories. git_test.j is pure and needs nothing.

An overlay can hide a missing use in the module it tests, because the overlay is spliced in after the module and its own use declarations resolve the module's references too. jennifer lint does not catch it either: it flags an unused import, not a missing one. A module can therefore pass its whole suite and fail the instant anything else imports it.

#Formatting

jennifer fmt preserves the wrapping you write and leaves this tree unchanged, so running it is a no-op.

Lint is the authority on width. fmt does not wrap an over-long line for you: a line past 100 columns is a lint finding whatever fmt makes of it.

The publish gate does not run fmt. It asks whether a deck is correct, and formatting is not correctness.

#Environment

#The registry is a separate repository

It carries its own copies of the four pure modules catalog.j, resolver.j, constraint.j and deckname.j, byte for byte. A change to one of those here almost certainly belongs there too, along with its overlay: two "identical" files with different tests are how they start drifting.

#Continuous integration

.github/workflows/test.yml runs every overlay and the linter against an interpreter built from the tip of the jennifer repository, because there is no released interpreter to install yet. That is deliberate rather than a workaround: jvc is the client half of a language that is still moving, so a break shows up in CI instead of in somebody's install. It is also the mirror image of the interpreter's own release gate, which runs this suite against a release candidate before tagging.

.github/workflows/release.yml builds and publishes the artifacts on a tag, with that suite as a gate in front.

.github/workflows/docs.yml builds this book and deploys it to https://jvc.jennifer-lang.dev/ on every push to main. The custom domain is bound by docs/CNAME, which Grimoire copies through as an ordinary asset: a Pages deployment publishes exactly what the artifact holds, so losing that file would unbind the domain silently. The workflow asserts it is there.