Define an implicit REPL target per binary/library target #225
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| @@ -138,6 +168,9 @@ def _mk_binary_rule(**kwargs): | |||
| doc = "File containing `Main` module.", | |||
| ) | |||
| ), | |||
| outputs = { | |||
| "repl": "%{name}-repl", | |||
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Bazel conventions seem to pretty consistently favour snake case. I think we should stick to Bazel conventions insofar as they exist for auto-generated target names.
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My logic here was:
- Names of (at least) library targets cannot contain underscores because they should be valid GHC package names (maybe now that we escape underscores it's not so important).
- So for consistency let's use dash here.
Snake case is understandable because foo-bar is not an identifier in Python/Skylark. But target names shouldn't necesserily be valid Skylark identifiers. In fact, at least in a project I was helping with recently I've seen a lot of targets named using dashes, such as xxx-doc, etc.
Anyway, the choice of the separator seems not so important to me.
| @@ -22,10 +22,14 @@ jobs: | |||
| command: bazel test //... --config=ci | |||
| - run: | |||
| name: Test REPL for libraries | |||
| command: bazel-bin/tests/haskell_repl/haskell_lib_repl -e ":quit" | |||
| command: | | |||
| bazel build //tests/repl-targets:hs-lib-repl | |||
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Does this have to be a two-line sequence, or as a user, can I bazel run --direct_run //tests/repl-targets:hs-lib-repl?
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I don't have Bazel 0.12 on my machine and CI doesn't have it either, so I think we should use what works with all versions. I don't know what --direct-run sets as current working directory and that's important for this script.
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Comment was not a statement, but a question. That said, Bazel had very poor support for this use case until v0.12. It's much better now, so we do need to make sure bazel run --direct_run is possible for users that have the right version, if it isn't already the case.
There's a nixpkgs PR for 0.12. I've been using it locally on my laptop.
| Every `haskell_binary` target also defines an optional REPL target that is | ||
| not built by default, but can be built on request. The name of the REPL | ||
| target is the same as the name of binary with `"-repl"` added at the end. | ||
| For example, the target above also defines `main-repl`. |
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How to load a library or binary into a REPL should be documented (use bazel run --direct_run?). Note that in future versions of Bazel, --direct_run might become the default. See bazelbuild/bazel@1fafc6f.
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I added something about this.
Close #220.
This PR removes the standalone
haskell_replrule and instead adds optional REPL outputs to everyhaskell_binaryandhaskell_librarytargets. The REPL outputs are not built unless we explicitly ask Bazel to build them and we can do so for any target. See the updated docs for more information how to use it, but I think it should be quite straightforward.