nixpkgs/pkgs/development/interpreters/dhall/build-dhall-package.nix
Gabriel Gonzalez 710038a5e6 Fix header for generated Dhall documentation
By default, `dhall-docs` uses the name of the input directory
as the initial component of the documentation header.  However,
since the input directory is built using Nix the header contains
the Nix store hash in the name, which then appears in the
generated documentation.

The fix is to override this default behavior by supplying the
`--package-name` flag to `dhall-docs`.
2021-01-14 09:50:44 +01:00

91 lines
2.7 KiB
Nix

{ dhall, dhall-docs, haskell, lib, lndir, runCommand, writeText }:
{ name
# Expressions to add to the cache before interpreting the code
, dependencies ? []
# A Dhall expression
#
# Carefully note that the following expression must be devoid of uncached HTTP
# imports. This is because the expression will be evaluated using an
# interpreter with HTTP support disabled, so all HTTP imports have to be
# protected by an integrity check that can be satisfied via cached
# dependencies.
#
# You can add a dependency to the cache using the preceding `dependencies`
# option
, code
# `buildDhallPackage` can include both a "source distribution" in
# `source.dhall` and a "binary distribution" in `binary.dhall`:
#
# * `source.dhall` is a dependency-free αβ-normalized Dhall expression
#
# * `binary.dhall` is an expression of the form: `missing sha256:${HASH}`
#
# This expression requires you to install the cache product located at
# `.cache/dhall/1220${HASH}` to successfully resolve
#
# By default, `buildDhallPackage` only includes "binary.dhall" to conserve
# space within the Nix store, but if you set the following `source` option to
# `true` then the package will also include `source.dhall`.
, source ? false
# Directory to generate documentation for (i.e. as the `--input` option to the
# `dhall-docs` command.)
#
# If `null`, then no documentation is generated.
, documentationRoot ? null
}:
let
# HTTP support is disabled in order to force that HTTP dependencies are built
# using Nix instead of using Dhall's support for HTTP imports.
dhallNoHTTP = haskell.lib.appendConfigureFlag dhall "-f-with-http";
file = writeText "${name}.dhall" code;
cache = ".cache";
data = ".local/share";
cacheDhall = "${cache}/dhall";
dataDhall = "${data}/dhall";
sourceFile = "source.dhall";
in
runCommand name { inherit dependencies; } ''
set -eu
mkdir -p ${cacheDhall}
for dependency in $dependencies; do
${lndir}/bin/lndir -silent $dependency/${cacheDhall} ${cacheDhall}
done
export XDG_CACHE_HOME=$PWD/${cache}
mkdir -p $out/${cacheDhall}
${dhallNoHTTP}/bin/dhall --alpha --file '${file}' > $out/${sourceFile}
SHA_HASH=$(${dhallNoHTTP}/bin/dhall hash <<< $out/${sourceFile})
HASH_FILE="''${SHA_HASH/sha256:/1220}"
${dhallNoHTTP}/bin/dhall encode --file $out/${sourceFile} > $out/${cacheDhall}/$HASH_FILE
echo "missing $SHA_HASH" > $out/binary.dhall
${lib.optionalString (!source) "rm $out/${sourceFile}"}
${lib.optionalString (documentationRoot != null) ''
mkdir -p $out/${dataDhall}
XDG_DATA_HOME=$out/${data} ${dhall-docs}/bin/dhall-docs --input '${documentationRoot}' --package-name '${name}' --output-link $out/docs
''}
''