[wasm] Fix native build failing when temp path contains parentheses

src/mono/wasm/Wasm.Build.Tests/NativeBuildTests.cs

@@ -41,6 +41,42 @@ public async Task SimpleNativeBuild(Configuration config, bool aot)
             await RunForPublishWithWebServer(new BrowserRunOptions(config, ExpectedExitCode: 42));
         }
 
+        [Theory]
+        [BuildAndRun(aot: false)]
+        [TestCategory("native-mono")]
+        [SkipOnPlatform(TestPlatforms.AnyUnix, "The cmd.exe quoting behavior this covers is Windows-specific.")]
+        public async Task NativeBuildWithSpecialCharsInTempPath(Configuration config, bool aot)
+        {
+            // Regression test for https://github.com/dotnet/runtime/issues/120327.
+            // Native compilation runs the compiler through a temporary batch file created under the
+            // temp directory. Windows user profile names can contain parentheses (e.g. "John(US)"),
+            // which puts parentheses in %TEMP%. `cmd /c "<path>"` then stripped the quotes around
+            // that path and mis-parsed it at the first '(', failing the native build with
+            // "'C:\Users\John' is not recognized as an internal or external command".
+            // The unicode chars additionally cover the UTF-8 (chcp 65001) handling in the same
+            // RunShellCommand path, which exists so non-ASCII (e.g. GB18030) temp/user paths work.
+            ProjectInfo info = CreateWasmTemplateProject(
+                Template.WasmBrowser,
+                config,
+                aot,
+                "parens_temp",
+                extraProperties: "<WasmBuildNative>true</WasmBuildNative>");
+
+            UpdateBrowserProgramFile();
+            ReplaceMainJsWithMinimalRunMain();
+
+            string tempWithParens = Path.Combine(BuildEnvironment.TmpPath, $"tmp ({GetRandomId()}) {s_unicodeChars}");
+            Directory.CreateDirectory(tempWithParens);
+            var envVars = new Dictionary<string, string>
+            {
+                ["TMP"] = tempWithParens,
+                ["TEMP"] = tempWithParens,
+            };
+
+            PublishProject(info, config, new PublishOptions(ExtraBuildEnvironmentVariables: envVars), isNativeBuild: true);
+            await RunForPublishWithWebServer(new BrowserRunOptions(config, ExpectedExitCode: 42));
+        }
+
         [Theory]
         [BuildAndRun(aot: true)]
         [TestCategory("native-mono")]

src/tasks/Common/Utils.cs

@@ -59,8 +59,14 @@ public static (int exitCode, string output) RunShellCommand(
                                         string? label=null)
     {
         string scriptFileName = CreateTemporaryBatchFile(command);
+        // The script path lives under the temp directory, which is typically inside the user
+        // profile (e.g. C:\Users\John(US)\AppData\Local\Temp\...). If that path contains cmd
+        // special characters such as '(' or ')', `cmd /c "<path>"` strips the surrounding quotes
+        // (because it sees special chars between the two quotes) and then mis-parses the now
+        // unquoted path at the first parenthesis. Use `/S` together with an extra pair of quotes
+        // so cmd strips only the outermost quotes and runs the still-quoted path verbatim.
         (string shell, string args) = RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
-                                                    ? ("cmd", $"/c \"{scriptFileName}\"")
+                                                    ? ("cmd", $"/S /c \"\"{scriptFileName}\"\"")
                                                     : ("/bin/sh", $"\"{scriptFileName}\"");
 
         string msgPrefix = label == null ? string.Empty : $"[{label}] ";