Add a test run on Windows with non-admin user and disabled developer mode

This way we can ensure that rubygems runs on a normal user account with symlinks disabled.
That is the default on an interactive Windows.

Author: larskanis

.github/workflows/rubygems.yml

@@ -37,7 +37,14 @@ jobs:
           - ruby: { name: truffleruby, value: truffleruby-24.2.1 }
             os: { name: Ubuntu, value: ubuntu-24.04 }
 
+          - ruby: { name: "no symlinks", value: 4.0.0 }
+            os: { name: Windows, value: windows-2025 }
+            symlink: off
+
     steps:
+      - name: disable development mode on Windows
+        run: powershell -c "Set-ItemProperty -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\AppModelUnlock -Name AllowDevelopmentWithoutDevLicense -Value 0"
+        if: matrix.symlink == 'off'
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
           persist-credentials: false
@@ -48,9 +55,14 @@ jobs:
           bundler: none
       - name: Install Dependencies
         run: bin/rake setup
+      - name: Run Test with non-Admin user
+        run: |
+          gem inst win32-process --no-doc --conservative
+          ruby bin/windows_run_as_user ruby -S rake test
+        if: matrix.symlink == 'off'
       - name: Run Test
         run: bin/rake test
-        if: matrix.ruby.name != 'truffleruby' && matrix.ruby.name != 'jruby'
+        if: matrix.ruby.name != 'truffleruby' && matrix.ruby.name != 'jruby' && matrix.symlink != 'off'
       - name: Run Test isolatedly
         run: bin/rake test:isolated
         if: matrix.ruby.name == '3.4' && matrix.os.name != 'Windows'

bin/windows_run_as_user

@@ -0,0 +1,30 @@
+require "win32/process"
+require "rbconfig"
+
+TESTUSER = "testuser"
+
+system("net user #{TESTUSER} /del 2>NUL")
+system("net user #{TESTUSER} \"Password123+\" /add") || raise
+system("icacls . /grant #{TESTUSER}:(OI)(CI)(IO)(F)")
+
+stdout_read, stdout_write = IO.pipe
+cmd = ARGV.join(" ")
+env = {
+    "TMP" => "#{Dir.pwd}/tmp",
+    "TEMP" => "#{Dir.pwd}/tmp"
+}
+pinfo = Process.create command_line: cmd,
+    with_logon: TESTUSER,
+    password: "Password123+",
+    cwd: Dir.pwd,
+    environment: ENV.to_h.merge(env).map{|k,v| "#{k}=#{v}" },
+    startup_info: { stdout: stdout_write, stderr: stdout_write }
+
+stdout_write.close
+out = stdout_read.read
+puts out
+
+# Wait for process to terminate
+sleep 0.1 while !(ecode=Process.get_exitcode(pinfo.process_id))
+
+exit ecode