`lib.debug.runTests` provides a unit test evaluator for Nix, but its
results are returned in a raw and difficult-to-read form.
Currently, different callers output the results in various ways:
`builtins.throw (builtins.toJSON failures)` and `builtins.throw ("Tests
failed: " + lib.generators.toPretty { } failures)` are both used.
This change adds a new `lib.debug.throwTestFailures` function which
displays the results nicely before throwing an exception (or returns
`null` if no failures are given), unifying these disparate call-sites.
First, each failing test is pretty-printed in a `trace` message:
```
trace: FAIL testDerivation:
Expected: <derivation a>
Result: <derivation b>
```
Then, an exception is thrown containing the number of tests that failed
(and their names), followed by the raw JSON of the results (for parity
with previous usage, and because `lib.generators.toPretty` sometimes
omits information that `builins.toJSON` includes):
```
error:
… while evaluating the file '...':
… caused by explicit throw
at /nix/store/.../lib/debug.nix:528:7:
527| in
528| throw (
| ^
529| builtins.seq traceFailures (
error: 1 tests failed:
- testDerivation
[{"expected":"/nix/store/xh7kyqp69mxkwspmi81a94m9xx74r8dr-a","name":"testDerivation","result":"/nix/store/503l84nir4zw57d1shfhai25bxxn16c6-b"}]
```
After final improvements to the official formatter implementation,
this commit now performs the first treewide reformat of Nix files using it.
This is part of the implementation of RFC 166.
Only "inactive" files are reformatted, meaning only files that
aren't being touched by any PR with activity in the past 2 months.
This is to avoid conflicts for PRs that might soon be merged.
Later we can do a full treewide reformat to get the rest,
which should not cause as many conflicts.
A CI check has already been running for some time to ensure that new and
already-formatted files are formatted, so the files being reformatted here
should also stay formatted.
This commit was automatically created and can be verified using
nix-build https://github.com/infinisil/treewide-nixpkgs-reformat-script/archive/a08b3a4d199c6124ac5b36a889d9099b4383463f.tar.gz \
--argstr baseRev b32a094368
result/bin/apply-formatting $NIXPKGS_PATH
Rebecca Turner