FromCabal.Name: prefix pkg names with _ if they can't be identifiers #672
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Seems this currently generates broken expressions since |
sternenseemann
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Resolved that, but there may be similar issues lurking! |
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Love it! |
Is the nixpkgs diff in the PR description from before or after that fix? |
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Before. |
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Do we want to do this for 25.11? I think it's basically ready and we could even add aliases for the attributes that would get changed. |
I'd say yes, let's do it. |
While we can quote attribute names, we can't use quoting to use arbitrary strings as function arguments in Nix unfortunately. This means we couldn't previously generate expressions for packages that depend on packages that start with numbers or clash with keywords. To fix this, we simply prefix the offending packages with an underscore. This mirrors an existing Nixpkgs convention (see e.g. pkgs._2bwm). This mapping work for all Hackage packages and is easily reversible by just removing the underscore. We can never introduce ambiguity this way since Cabal doesn't allow underscores in package names. Cabal packages not conforming to Hackage's restrictions won't work yet. For this, we would need to implement some kind of encoding. Resolves #163. Resolves #164.
The package expression for acme-everything is huge since it has to list all packages released to Hackage as of 2018 twice. As this package isn't actually useful and probably doesn't even have a valid install plan, we can remove it to keep the size of hackage-packages.nix in check. In the future, such exclusions should be decided by configurable exclusions as proposed in #667. It may be a prudent idea to use the spam and acme categories of Hackage as a baseline for package exclusions. This partially reverts commit d105bfc.
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| nixpkgs <- readNixpkgPackageMap nixpkgsRepository (Just "{ config = { allowAliases = false; }; }") | ||
| preferredVersions <- readPreferredVersions (fromMaybe (hackageRepository </> "preferred-versions") preferredVersionsFile) | ||
| let fixup = over (at "hermes") (fmap (set (contains "1.3.4.3") False)) -- TODO: https://github.com/haskell/hackage-server/issues/436 | ||
| let fixup = Map.delete "acme-everything" -- TODO(@wolfgangwalther): remove after https://github.com/NixOS/cabal2nix/pull/667 |
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- In general, one should Identifier and its instances to render and parse Identifiers. quote has been relegated to an Internals section since it is only required by the test suite at the moment. It may be nice to remove it at some point. - needsQuoting deals with arbitrary strings and would normally be used to judge whether a given String should be converted to an Identifier directly or first be subject to some kind of substitution so that it does not need to be quoted (see #672). nixKeywords is an internal definition involved with this which is also used in the test suites.
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While we can quote attribute names, we can't use quoting to use arbitrary strings as function arguments in Nix unfortunately. This means we couldn't previously generate expressions for packages that depend on packages that start with numbers or clash with keywords.
To fix this, we simply prefix the offending packages with an underscore. This mirrors an existing Nixpkgs convention (see e.g. pkgs._2bwm). This mapping work for all Hackage packages and is easily reversible by just removing the underscore. We can never introduce ambiguity this way since Cabal doesn't allow underscores in package names.
Cabal packages not conforming to Hackage's restrictions won't work yet. For this, we would need to implement some kind of encoding.
Resolves #163.
Resolves #164.
Nixpkgs diff
Note that I removed the addition of
acme-everythingwhich accounts for most of the diff so that it fits in the github comment. We should probably putacme-everythingin exclude packages or a similar mechanism.