neovim: add some tests

To test the generated RC is included in the file and that we have the
option not to wrap the RC.

run:
nix-build -A tests.vim

pkgs/applications/editors/neovim/utils.nix

···
     , vimAlias ? false
     , viAlias ? false
     , configure ? {}
+    , extraName ? ""
   }:
     let
       /* for compatibility with passing extraPythonPackages as a list; added 2018-07-11 */
···
         extraPython3Packages = compatFun extraPython3Packages;
         inherit withNodeJs withRuby viAlias vimAlias;
         inherit configure;
+        inherit extraName;
       };
     in
     assert withPython -> throw "Python2 support has been removed from neovim, please remove withPython and extraPythonPackages.";

pkgs/applications/editors/neovim/wrapper.nix

···
     # set to false if you want to control where to save the generated config
     # (e.g., in ~/.config/init.vim or project/.nvimrc)
     , wrapRc ? true
+    , neovimRcContent ? ""
     , ...
   }@args:
   let
 
     wrapperArgsStr = if isString wrapperArgs then wrapperArgs else lib.escapeShellArgs wrapperArgs;
 
-  # If configure != {}, we can't generate the rplugin.vim file with e.g
-  # NVIM_SYSTEM_RPLUGIN_MANIFEST *and* NVIM_RPLUGIN_MANIFEST env vars set in
-  # the wrapper. That's why only when configure != {} (tested both here and
-  # when postBuild is evaluated), we call makeWrapper once to generate a
-  # wrapper with most arguments we need, excluding those that cause problems to
-  # generate rplugin.vim, but still required for the final wrapper.
-  finalMakeWrapperArgs =
-    [ "${neovim}/bin/nvim" "${placeholder "out"}/bin/nvim" ]
-    ++ [ "--set" "NVIM_SYSTEM_RPLUGIN_MANIFEST" "${placeholder "out"}/rplugin.vim" ]
-    ++ optionals wrapRc [ "--add-flags" "-u ${writeText "init.vim" args.neovimRcContent}" ]
-    ;
+    # If configure != {}, we can't generate the rplugin.vim file with e.g
+    # NVIM_SYSTEM_RPLUGIN_MANIFEST *and* NVIM_RPLUGIN_MANIFEST env vars set in
+    # the wrapper. That's why only when configure != {} (tested both here and
+    # when postBuild is evaluated), we call makeWrapper once to generate a
+    # wrapper with most arguments we need, excluding those that cause problems to
+    # generate rplugin.vim, but still required for the final wrapper.
+    finalMakeWrapperArgs =
+      [ "${neovim}/bin/nvim" "${placeholder "out"}/bin/nvim" ]
+      ++ [ "--set" "NVIM_SYSTEM_RPLUGIN_MANIFEST" "${placeholder "out"}/rplugin.vim" ]
+      ++ optionals wrapRc [ "--add-flags" "-u ${writeText "init.vim" neovimRcContent}" ]
+      ;
   in
   assert withPython2 -> throw "Python2 support has been removed from the neovim wrapper, please remove withPython2 and python2Env.";
 
···
     preferLocalBuild = true;
 
     nativeBuildInputs = [ makeWrapper ];
-    passthru = { unwrapped = neovim; };
+    passthru = {
+      unwrapped = neovim;
+      initRc = neovimRcContent;
+    };
 
     meta = neovim.meta // {
       # To prevent builds on hydra

pkgs/test/vim/default.nix

···
 { vimUtils, vim_configurable, writeText, neovim, vimPlugins
 , lib, fetchFromGitHub, neovimUtils, wrapNeovimUnstable
 , neovim-unwrapped
+, fetchFromGitLab
+, pkgs
 }:
 let
   inherit (vimUtils) buildVimPluginFrom2Nix;
+  inherit (neovimUtils) makeNeovimConfig;
 
   packages.myVimPackage.start = with vimPlugins; [ vim-nix ];
 
···
     }
   ];
 
-  nvimConfNix = neovimUtils.makeNeovimConfig {
+  nvimConfNix = makeNeovimConfig {
+    inherit plugins;
+    customRC = ''
+      " just a comment
+    '';
+  };
+
+  nvimConfDontWrap = makeNeovimConfig {
     inherit plugins;
     customRC = ''
       " just a comment
     '';
   };
 
-  wrapNeovim = suffix: config:
+  wrapNeovim2 = suffix: config:
     wrapNeovimUnstable neovim-unwrapped (config // {
       extraName = suffix;
-      wrapRc = true;
     });
+
+  nmt = fetchFromGitLab {
+    owner = "rycee";
+    repo = "nmt";
+    rev = "d2cc8c1042b1c2511f68f40e2790a8c0e29eeb42";
+    sha256 = "1ykcvyx82nhdq167kbnpgwkgjib8ii7c92y3427v986n2s5lsskc";
+  };
+
+  runTest = neovim-drv: buildCommand:
+    pkgs.runCommandLocal "test-${neovim-drv.name}" ({
+      nativeBuildInputs = [ ];
+      meta.platforms = neovim-drv.meta.platforms;
+    }) (''
+      source ${nmt}/bash-lib/assertions.sh
+      vimrc="${writeText "init.vim" neovim-drv.initRc}"
+      vimrcGeneric="$out/patched.vim"
+      mkdir $out
+      ${pkgs.perl}/bin/perl -pe "s|\Q$NIX_STORE\E/[a-z0-9]{32}-|$NIX_STORE/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-|g" < "$vimrc" > "$vimrcGeneric"
+    '' + buildCommand);
+
 in
-{
+  pkgs.recurseIntoAttrs (
+rec {
   vim_empty_config = vimUtils.vimrcFile { beforePlugins = ""; customRC = ""; };
 
   ### neovim tests
   ##################
-  nvim_with_plugins = wrapNeovim "-with-plugins" nvimConfNix;
+  nvim_with_plugins = wrapNeovim2 "-with-plugins" nvimConfNix;
 
   nvim_via_override = neovim.override {
+    extraName = "-via-override";
     configure = {
       packages.foo.start = [ vimPlugins.ale ];
       customRC = ''
···
       '';
     };
   };
+
+
+  # nixpkgs should detect that no wrapping is necessary
+  nvimShouldntWrap = wrapNeovim2 "-should-not-wrap" nvimConfNix;
+
+
+  # this will generate a neovimRc content but we disable wrapping
+  nvimDontWrap = wrapNeovim2 "-dont-wrap" (makeNeovimConfig {
+    wrapRc = false;
+    customRC = ''
+      " this shouldn't trigger the creation of an init.vim
+    '';
+  });
+
+  nvim_dontwrap-test = runTest nvimDontWrap ''
+      ! grep "-u" ${nvimDontWrap}/bin/nvim
+  '';
+
+  nvim_via_override-test = runTest nvim_via_override ''
+      assertFileContent \
+        "$vimrcGeneric" \
+        "${./neovim-override.vim}"
+  '';
 
   ### vim tests
   ##################
···
   test_nvim_with_remote_plugin = neovim.override {
     configure.pathogen.pluginNames = with vimPlugins; [ deoplete-nvim ];
   };
-}
+})

pkgs/test/vim/neovim-override.vim

···
+" configuration generated by NIX
+set nocompatible
+
+set packpath^=/nix/store/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-vim-pack-dir
+set runtimepath^=/nix/store/eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee-vim-pack-dir
+
+:help ale