From d399cd2f7d10a83fac1f84bea51afc0f160560ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Guillermo=20L=C3=B3pez?= <guillermo.lopez@outlook.com>
Date: Fri, 13 Mar 2026 20:59:28 +0100
Subject: [PATCH] Throw if `npm install` returns non-zero exit code

Closes #251
---
 resources/NpmDsc/NpmDsc.psm1  | 8 +++++++-
 tests/NpmDsc/NpmDsc.tests.ps1 | 4 ++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/resources/NpmDsc/NpmDsc.psm1 b/resources/NpmDsc/NpmDsc.psm1
index 64f7b4bc..a418bf66 100644
--- a/resources/NpmDsc/NpmDsc.psm1
+++ b/resources/NpmDsc/NpmDsc.psm1
@@ -17,8 +17,14 @@ function Invoke-Npm {
         [Parameter(Mandatory = $true)]
         [string]$Command
     )
+        $value = Invoke-Expression -Command "npm $Command"
 
-    return Invoke-Expression -Command "npm $Command"
+        if ($LASTEXITCODE -ne 0) {
+            $errors = Get-NpmErrorMessages -LogPath (GetNpmPath)
+            throw "Command 'npm $($Command.Trim())' failed: $($errors -join '; ')"
+        }
+
+        return $value
 }
 
 function Set-PackageDirectory {
diff --git a/tests/NpmDsc/NpmDsc.tests.ps1 b/tests/NpmDsc/NpmDsc.tests.ps1
index 3162aeee..0b1472e2 100644
--- a/tests/NpmDsc/NpmDsc.tests.ps1
+++ b/tests/NpmDsc/NpmDsc.tests.ps1
@@ -85,6 +85,10 @@ Describe 'NpmPackage' {
         $finalState.InDesiredState | Should -Be $true
     }
 
+    It 'Throws if npm returns non-zero exit code' -Skip:(!$IsWindows) {
+        { Invoke-Npm '!' } | Should -Throw "Command 'npm !' failed:*"
+    }
+
     It 'Performs whatif operation successfully' -Skip:(!$IsWindows) {
         $whatIfState = @{
             Name   = 'react'