NuGetCommandV2 fails gracefully when used on ubuntu 24 without mono

Tasks/NuGetCommandV2/Strings/resources.resjson/en-US/resources.resjson

@@ -136,5 +136,7 @@
   "loc.messages.Error_NugetFailedWithCodeAndErr": "The nuget command failed with exit code(%s) and error(%s)",
   "loc.messages.Warning_IncludeNuGetOrgEnabled": "IncludeNugetOrg is currently enabled for this task. To resolve this warning, edit your build task and set 'includeNuGetOrg' to 'false' or deselect 'Use packages from NuGet.org'.",
   "loc.messages.Error_IncludeNuGetOrgEnabled": "Packages failed to restore. Edit your build task and set 'includeNuGetOrg' to 'false' or deselect 'Use packages from NuGet.org'.",
-  "loc.messages.Warning_UnsupportedServiceConnectionAuth": "The service connection does not use a supported authentication method. Please use a service connection with personal access token based auth."
+  "loc.messages.Warning_UnsupportedServiceConnectionAuth": "The service connection does not use a supported authentication method. Please use a service connection with personal access token based auth.",
+  "loc.messages.LIB_WhichNotFound_Linux": "Unable to locate executable file: '%s'. Please verify either the file path exists or the file can be found within a directory specified by the PATH environment variable. Also check the file mode to verify the file is executable.",
+  "loc.messages.Error_IncompatibleUbuntuVersion": "The task has failed because you are using Ubuntu 22.04 without mono. See [link] for more information."
 }

Tasks/NuGetCommandV2/UbuntuDetectionHelper.ts

@@ -0,0 +1,77 @@
+import * as os from 'os';
+import * as fs from 'fs';
+import * as tl from "azure-pipelines-task-lib/task";
+
+export function detectUnsupportedUbuntuVersion(): boolean {
+    const platform = os.platform();
+    if (platform === 'linux') {
+        const lbsContents = _readLinuxVersionFile();
+        const distribution = _parseLinuxDistribution(lbsContents);
+        if (distribution === 'Ubuntu') {
+            const version = parseFloat(_parseUbuntuVersion(lbsContents));
+            if (version >= 22.04) {
+                try {
+                    tl.which('mono', true);
+                }
+                catch (error) {
+                    if (error.message === tl.loc("LIB_WhichNotFound_Linux", 'mono')) {
+                        return true;
+                    }
+                    throw error;
+                }
+            }
+        }
+    }
+    return false
+}
+
+function _readLinuxVersionFile(): string {
+    const lsbReleaseFile = '/etc/lsb-release';
+    const osReleaseFile = '/etc/os-release';
+    let contents = '';
+
+    if (fs.existsSync(lsbReleaseFile)) {
+        contents = fs.readFileSync(lsbReleaseFile).toString();
+    } else if (fs.existsSync(osReleaseFile)) {
+        contents = fs.readFileSync(osReleaseFile).toString();
+    }
+
+    return contents;
+}
+
+function _parseLinuxDistribution(lbsContents): string {
+    const lines = lbsContents.split('\n');
+    for (const line of lines) {
+        const parts = line.split('=');
+        if (
+            parts.length === 2 &&
+            (parts[0].trim() === 'DISTRIB_ID' ||
+                parts[0].trim() === 'DISTRIB_DESCRIPTION')
+        ) {
+            return parts[1]
+                .trim()
+                .split(/\s+/)[0]
+                .replace(/^"/, '')
+                .replace(/"$/, '');
+        }
+    }
+    return '';
+}
+
+function _parseUbuntuVersion(lbsContents): string {
+    const lines = lbsContents.split('\n');
+    for (const line of lines) {
+        const parts = line.split('=');
+        if (
+            parts.length === 2 &&
+            (parts[0].trim() === 'VERSION_ID' ||
+                parts[0].trim() === 'DISTRIB_RELEASE')
+        ) {
+            return parts[1]
+                .trim()
+                .replace(/^"/, '')
+                .replace(/"$/, '');
+        }
+    }
+    return '';
+}

Tasks/NuGetCommandV2/nugetcommandmain.ts

@@ -9,6 +9,7 @@ import * as nugetCustom from "./nugetcustom";
 import * as nugetPack from "./nugetpack";
 import * as nugetPublish from "./nugetpublisher";
 import * as nugetRestore from "./nugetrestore";
+import * as ubuntuDetectionHelper from "./UbuntuDetectionHelper";
 
 const NUGET_EXE_CUSTOM_LOCATION: string = "NuGetExeCustomLocation";
 
@@ -21,6 +22,10 @@ async function main(): Promise<void> {
     let nugetVersion: string;
     let msBuildVersion: string;
     try {
+        if (ubuntuDetectionHelper.detectUnsupportedUbuntuVersion()) {
+            tl.setResult(tl.TaskResult.Failed, tl.loc("Error_IncompatibleUbuntuVersion"));
+            return;
+        }
         msBuildVersion = await nuGetGetter.getMSBuildVersionString();
         nuGetPath = tl.getVariable(nuGetGetter.NUGET_EXE_TOOL_PATH_ENV_VAR)
                     || tl.getVariable(NUGET_EXE_CUSTOM_LOCATION);