Introduce preInstallCustomCommands attribute for node modules

preInstallCustomCommands allows to run arbitrary shell scripts, running per node module pinned to given version - such approach, allows for fixing node modules which would otherwise be unfit for running on NixOS

README.md

@@ -85,6 +85,21 @@ npmlock2nix.node_modules {
   #   };
   # };
 
+  # You can run arbitrary shell operation for given module in given version,
+  # using preInstallCustomCommands attribute. Below you see how you can
+  # override path to esbuild module, depending on which version in needed.
+  # This approach comes in handy, if node_modules have two competing versions
+  # of the same module.
+  # Please note: set key must adhere to the pattern <module_name>@<module_version>.
+  # preInstallCustomCommands = {
+  #   "[email protected]" = [''
+  #       sed -i -e 's|process.env.ESBUILD_BINARY_PATH|"${esbuild_0_8_57}/bin/esbuild"|g' ./install.js
+  #   ''];
+  #   "[email protected]" = [''
+  #       sed -i -e 's|process.env.ESBUILD_BINARY_PATH|"${esbuild_0_11_12}/bin/esbuild"|g' ./install.js
+  #   ''];
+  # };
+
   # You can set any desired environment by just adding them to this set just
   # like you would do in a regular `stdenv.mkDerivation` invocation:
   # MY_ENVIRONMENT_VARIABLE = "foo";

internal.nix

@@ -231,12 +231,15 @@ rec {
     , preBuild ? ""
     , postBuild ? ""
     , preInstallLinks ? { } # set that describes which files should be linked in a specific packages folder
+    , preInstallCustomCommands ? { }
     , ...
     }@args:
       assert (builtins.typeOf preInstallLinks != "set") ->
         throw "[npmlock2nix] `preInstallLinks` must be an attributeset of attributesets";
+      assert (builtins.typeOf preInstallCustomCommands != "set") ->
+        throw "[npmlock2nix] `preInstallCustomCommands` must be an attributeset of list of commands";
       let
-        cleanArgs = builtins.removeAttrs args [ "src" "packageJson" "packageLockJson" "buildInputs" "nativeBuildInputs" "nodejs" "preBuild" "postBuild" "preInstallLinks" ];
+        cleanArgs = builtins.removeAttrs args [ "src" "packageJson" "packageLockJson" "buildInputs" "nativeBuildInputs" "nodejs" "preBuild" "postBuild" "preInstallLinks" "preInstallCustomCommands" ];
         lockfile = readLockfile packageLockJson;
 
         preinstall_node_modules = writeTextFile {
@@ -261,11 +264,22 @@ rec {
                   '')
                   preInstallLinks
               );
+              preInstallCustomCmds = lib.concatStringsSep "\n" (
+                (lib.mapAttrsToList
+                  (name_at_version: cmds: ''
+                    if [ "$npm_package_name@$npm_package_version" == "${name_at_version}" ]; then
+                      ${lib.concatStringsSep "\n" cmds}
+                    fi''
+                  )
+                )
+                  preInstallCustomCommands
+              );
             in
             ''
               #! ${stdenv.shell}
 
               ${preInstallLinkCommands}
+              ${preInstallCustomCmds}
 
               if grep -I -q -r '/bin/' .; then
                 source $TMP/preinstall-env