Nix fixes (idris-lang#1623)

.github/workflows/ci-nix.yml

@@ -18,6 +18,4 @@ jobs:
     - uses: cachix/install-nix-action@v12
       with:
         install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20210126_f15f0b8/install
-        extra_nix_config: |
-          experimental-features = nix-command flakes
-    - run: nix flake check
+    - run: nix-build -A checks.x86_64-linux

INSTALL.md

@@ -34,8 +34,8 @@ of `make` in the following steps.
 
 ### 1: Set installation target directory
 
-- Change the `PREFIX` in `config.mk` to the absolute path of your chosen installation destination. The default is to install in
-  `$HOME/.idris2`
+- Change the `PREFIX` in `config.mk` to the absolute path of your chosen
+installation destination. The default is to install in `$HOME/.idris2`
 
 If you have an existing Idris 2, go to Step 3. Otherwise, read on...
 
@@ -81,7 +81,9 @@ that everything has worked correctly. Assuming that `idris2` is in your
 `PATH`.
 
 - `make clean` -- to make sure you're building everything with the new version
-- `make all && make install` -- OR `make all IDRIS2_BOOT='idris2 --codegen racket' && make install` if using Racket.
+- `make all && make install` -- OR
+`make all IDRIS2_BOOT='idris2 --codegen racket' && make install`
+if using Racket.
 
 ### 5: Running tests
 
@@ -121,6 +123,7 @@ eval "$(idris2 --bash-completion-script idris2)"
 You can also add it to your `.bashrc` file.
 
 #### For ZSH Users
+
 From within ZSH, run the following commands:
 
 ```sh
@@ -151,16 +154,17 @@ brew install idris2
 
 ### Installing from nix
 
-If you are a [nix](https://nixos.org/features.html) user you can install Idris 2 together with all the requirements
-by running the following command:
+If you are a [nix](https://nixos.org/features.html) user you can install Idris
+2 together with all the requirements by running the following command:
 
 ```sh
 nix-env -i idris2
 ```
 
 ### Install from nix flakes
 
-If you are a [nix flakes](https://nixos.wiki/wiki/Flakes) user you can install Idris 2 together with all the requirements by running the following command:
+If you are a [nix flakes](https://nixos.wiki/wiki/Flakes) user you can install
+Idris 2 together with all the requirements by running the following command:
 
 ```sh
 nix profile install github:idris-lang/Idris2
@@ -170,8 +174,9 @@ nix profile install github:idris-lang/Idris2
 
 ### Run on emacs using nix flakes
 
-If you are a [nix flakes](https://nixos.wiki/wiki/Flakes) user you can run Idris 2 in emacs by running the following command:
+If you are a [nix flakes](https://nixos.wiki/wiki/Flakes) user you can run
+Idris 2 in emacs by running the following command:
 
 ```sh
-nix run idris-lang/Idris2#emacs-with-idris idrisCode.idr
+nix run github:idris-lang/Idris2#emacs-with-idris idrisCode.idr
 ```

default.nix

@@ -1,3 +1,3 @@
 (import (fetchTarball https://github.com/edolstra/flake-compat/archive/master.tar.gz) {
-  src = builtins.fetchGit ./.;
+  src = ./.;
 }).defaultNix

nix/package.nix

@@ -9,6 +9,7 @@
 , racket
 , gambit
 , nodejs
+, zsh
 }:
 
 # Uses scheme to bootstrap the build of idris2
@@ -19,7 +20,8 @@ stdenv.mkDerivation rec {
   src = ../.;
 
   strictDeps = true;
-  nativeBuildInputs = [ makeWrapper clang chez ];
+  nativeBuildInputs = [ makeWrapper clang chez ]
+    ++ lib.optional stdenv.isDarwin [ zsh ];
   buildInputs = [ chez gmp ];
 
   prePatch = ''
@@ -38,39 +40,34 @@ stdenv.mkDerivation rec {
   # TODO: Move this into its own derivation, such that this can be changed
   #       without having to recompile idris2 every time.
   postInstall = let
-    includedLibs = [ "base" "contrib" "network" "prelude" "test" ];
     name = "${pname}-${version}";
-    packagePaths = builtins.map (l: "$out/${name}/${l}-${version}") includedLibs;
-    additionalIdris2Paths = builtins.concatStringsSep ":" packagePaths;
-    globalLibraries = [ "\\$HOME/.nix-profile/lib/${name}" "/run/current-system/sw/lib/${name}" ];
+    globalLibraries = [
+      "\\$HOME/.nix-profile/lib/${name}"
+      "/run/current-system/sw/lib/${name}"
+      "$out/${name}"
+    ];
     globalLibrariesPath = builtins.concatStringsSep ":" globalLibraries;
   in ''
     # Remove existing idris2 wrapper that sets incorrect LD_LIBRARY_PATH
     rm $out/bin/idris2
-    # Move actual idris2 binary
+
+    # The only thing we need from idris2_app is the actual binary
     mv $out/bin/idris2_app/idris2.so $out/bin/idris2
-    # After moving the binary, there is nothing left in idris2_app that isn't
-    # either contained in lib/ or is useless to us.
     rm $out/bin/idris2_app/*
     rmdir $out/bin/idris2_app
+
     # idris2 needs to find scheme at runtime to compile
-    # idris2 installs packages with --install into the path given by PREFIX.
-    # Since PREFIX is in nix-store, it is immutable so --install does not work.
-    # If the user redefines PREFIX to be able to install packages, idris2 will
-    # not find the libraries and packages since all paths are relative to
-    # PREFIX by default.
-    # We explicitly make all paths to point to nix-store, such that they are
-    # independent of what IDRIS2_PREFIX is. This allows the user to redefine
-    # IDRIS2_PREFIX and use --install as expected.
+    # idris2 installs packages with --install into the path given by
+    #   IDRIS2_PREFIX. We set that to a default of ~/.idris2, to mirror the
+    #   behaviour of the standard Makefile install.
     # TODO: Make support libraries their own derivation such that
     #       overriding LD_LIBRARY_PATH is unnecessary
-    # TODO: Maybe set IDRIS2_PREFIX to the users home directory
     wrapProgram "$out/bin/idris2" \
       --set-default CHEZ "${chez}/bin/scheme" \
+      --set-default IDRIS2_PREFIX "~/.idris2" \
       --suffix IDRIS2_LIBS ':' "$out/${name}/lib" \
       --suffix IDRIS2_DATA ':' "$out/${name}/support" \
-      --suffix IDRIS2_PATH ':' "${additionalIdris2Paths}" \
-      --run "export IDRIS2_PACKAGE_PATH=\$IDRIS2_PACKAGE_PATH:${globalLibrariesPath}" \
+      --suffix IDRIS2_PACKAGE_PATH ':' "${globalLibrariesPath}" \
       --suffix LD_LIBRARY_PATH ':' "$out/${name}/lib"
   '';
 }