npmHooks.npmInstallHook: pass install flags to prune

doc/languages-frameworks/javascript.section.md

@@ -196,7 +196,7 @@ buildNpmPackage rec {
 * `makeCacheWritable`: Whether to make the cache writable prior to installing dependencies. Don't set this unless npm tries to write to the cache directory, as it can slow down the build.
 * `npmBuildScript`: The script to run to build the project. Defaults to `"build"`.
 * `npmFlags`: Flags to pass to all npm commands.
-* `npmInstallFlags`: Flags to pass to `npm ci`.
+* `npmInstallFlags`: Flags to pass to `npm ci` and `npm prune`.
 * `npmBuildFlags`: Flags to pass to `npm run ${npmBuildScript}`.
 * `npmPackFlags`: Flags to pass to `npm pack`.
 

pkgs/build-support/node/build-npm-package/default.nix

@@ -17,7 +17,7 @@
 , npmBuildScript ? "build"
   # Flags to pass to all npm commands.
 , npmFlags ? [ ]
-  # Flags to pass to `npm ci`.
+  # Flags to pass to `npm ci` and `npm prune`.
 , npmInstallFlags ? [ ]
   # Flags to pass to `npm rebuild`.
 , npmRebuildFlags ? [ ]

pkgs/build-support/node/build-npm-package/hooks/npm-install-hook.sh

@@ -27,7 +27,7 @@ npmInstallHook() {
     local -r nodeModulesPath="$packageOut/node_modules"
 
     if [ ! -d "$nodeModulesPath" ]; then
-        npm prune --omit dev
+        npm prune --omit dev $npmInstallFlags "${npmInstallFlagsArray[@]}" $npmFlags "${npmFlagsArray[@]}"
         find node_modules -maxdepth 1 -type d -empty -delete
 
         cp -r node_modules "$nodeModulesPath"