Kotlin `private` on a top-level declaration is file-scoped, so every leaf
composable in the two screens was invisible even to the JVM test source set,
which is a friend of main. The only three declarations src/test could name were
ConverterScreen, JoinScreen and AppRoot -- there was nothing to write a test
against, which is why #52 could not be started as filed.
`internal` is the same choice MainActivity already documents for Destination:
the unit tests can name it, and it stays invisible to anything outside the
module. Eleven declarations in ConverterScreen and FileRow in JoinScreen.
The tag table is the other half. Tests reference a symbol rather than a literal,
which is what keeps the five children that follow independent: "Cancel", "Start
over" and "Save file" are each rendered by both screens and by more than one
state branch, so rewording one would otherwise redden several PRs at once and no
diff would explain why. There were zero testTag, semantics or contentDescription
calls anywhere in main before this.
Every tag is applied inside main. A tag a test hands down as a Modifier proves
only that the test set it -- it would survive the affordance losing its own tag
entirely, which is the vacuous shape CLAUDE.md records nine of in one review.
That is why FileRow and DetailRow derive theirs from data they already hold
rather than taking an index from the call site.
TestTags is public rather than internal, and R38.8 is the reason. It reads the
table from androidTest, and whether that is a friend source set of main under
AGP 9 had no in-tree answer -- nothing referenced a main internal from there.
Settled by compiling one: it is a friend, so internal would work today. Public
anyway, because that friendship is AGP wiring rather than something this project
states, and the KDoc now carries the measurement so nobody has to repeat it.
Smoke tests cover each leaf: it renders, and its tag resolves to exactly one
node. Counting rather than asserting existence is deliberate, since a duplicated
tag fails differently depending on which finder a later test happens to use. The
state-branch tags -- Convert, Cancel, Save file, Start over, the progress bars --
have no bite yet: reaching a branch needs the state seam R38.5 extracts, and the
state matrix is R38.6/R38.7 by design.
Five mutations, all red on the named test alone: FORMAT_CHIPS deleted,
FILE_CARD_NAME deleted, detailRow's tag no longer derived from its label,
FileRow's no longer derived from its name, and JOIN_MORE given JOIN's value --
the last caught only by the uniqueness check, which is what it is for.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
JMR-devandClaude Opus 5
df2e42a2b3