Fix GoToolV0 to conditionally set GOROOT only for Go < 1.9 (#20796)

Tasks/GoToolV0/Tests/L0.ts

@@ -86,7 +86,8 @@ describe('GoToolV0 Suite', function() {
         let tr: MockTestRunner = new MockTestRunner(tp);
         await tr.runAsync();
         assert(tr.succeeded, 'Should have succeeded');
-        assert(tr.stdOutContained('##vso[task.setvariable variable=GOROOT'), 'Should set GOROOT');
+        // GOROOT should NOT be set for modern Go versions (1.21.3 >= 1.9)
+        assert(tr.stdOutContained('Skipping GOROOT for modern Go version'), 'Should skip GOROOT for modern version');
         assert(tr.stdOutContained('##vso[task.setvariable variable=GOPATH'), 'Should set GOPATH');
         assert(tr.stdOutContained('##vso[task.setvariable variable=GOBIN'), 'Should set GOBIN');
     });
@@ -224,4 +225,32 @@ describe('GoToolV0 Suite', function() {
         assert(tr.failed, 'Should have failed');
         assert(tr.stdOutContained('Invalid download URL'), 'Should reject unsupported URL from environment variable');
     });
+
+    // GOROOT behavior tests (issue #20796)
+    it('Should NOT set GOROOT for modern Go versions (>= 1.9)', async () => {
+        let tp = path.join(__dirname, 'L0GorootModernVersion.js');
+        let tr: MockTestRunner = new MockTestRunner(tp);
+        await tr.runAsync();
+        assert(tr.succeeded, 'Should have succeeded');
+        assert(tr.stdOutContained('Skipping GOROOT for modern Go version'), 'Should skip GOROOT for Go >= 1.9');
+        assert(!tr.stdOutContained('##vso[task.setvariable variable=GOROOT'), 'Should NOT set GOROOT for modern versions');
+    });
+
+    it('Should set GOROOT for legacy Go versions (< 1.9)', async () => {
+        let tp = path.join(__dirname, 'L0GorootLegacyVersion.js');
+        let tr: MockTestRunner = new MockTestRunner(tp);
+        await tr.runAsync();
+        assert(tr.succeeded, 'Should have succeeded');
+        assert(tr.stdOutContained('Setting GOROOT for Go version < 1.9'), 'Should set GOROOT for Go < 1.9');
+        assert(tr.stdOutContained('##vso[task.setvariable variable=GOROOT'), 'Should set GOROOT for legacy versions');
+    });
+
+    it('Should NOT set GOROOT for Go 1.9.0 (boundary version)', async () => {
+        let tp = path.join(__dirname, 'L0GorootBoundaryVersion.js');
+        let tr: MockTestRunner = new MockTestRunner(tp);
+        await tr.runAsync();
+        assert(tr.succeeded, 'Should have succeeded');
+        assert(tr.stdOutContained('Skipping GOROOT for modern Go version'), 'Should skip GOROOT for Go 1.9.0');
+        assert(!tr.stdOutContained('##vso[task.setvariable variable=GOROOT'), 'Should NOT set GOROOT for Go 1.9.0');
+    });
 });

Tasks/GoToolV0/Tests/L0GorootBoundaryVersion.ts

@@ -0,0 +1,37 @@
+import tmrm = require('azure-pipelines-task-lib/mock-run');
+import path = require('path');
+
+let taskPath = path.join(__dirname, '..', 'gotool.js');
+let tmr: tmrm.TaskMockRunner = new tmrm.TaskMockRunner(taskPath);
+
+// Test Go 1.9.0 exactly (boundary version) - GOROOT should NOT be set
+tmr.setInput('version', '1.9.0');
+
+// Mock environment variables
+process.env['Agent.TempDirectory'] = path.join(__dirname, 'temp');
+
+// Mock tool lib functions
+tmr.registerMock('azure-pipelines-tool-lib/tool', {
+    findLocalTool: function(toolName: string, version: string) {
+        console.log('Found cached Go version');
+        return '/mock/cache/go/1.9.0';
+    },
+    prependPath: function(toolPath: string) {
+        console.log(`Adding to PATH: ${toolPath}`);
+    }
+});
+
+// Mock os module
+tmr.registerMock('os', {
+    platform: () => 'linux',
+    arch: () => 'x64'
+});
+
+// Mock telemetry
+tmr.registerMock('azure-pipelines-tasks-utility-common/telemetry', {
+    emitTelemetry: function(area: string, feature: string, properties: any) {
+        console.log(`Telemetry: ${area}.${feature}`);
+    }
+});
+
+tmr.run();

Tasks/GoToolV0/Tests/L0GorootLegacyVersion.ts

@@ -0,0 +1,37 @@
+import tmrm = require('azure-pipelines-task-lib/mock-run');
+import path = require('path');
+
+let taskPath = path.join(__dirname, '..', 'gotool.js');
+let tmr: tmrm.TaskMockRunner = new tmrm.TaskMockRunner(taskPath);
+
+// Test legacy Go version (< 1.9) - GOROOT SHOULD be set
+tmr.setInput('version', '1.8.7');
+
+// Mock environment variables
+process.env['Agent.TempDirectory'] = path.join(__dirname, 'temp');
+
+// Mock tool lib functions
+tmr.registerMock('azure-pipelines-tool-lib/tool', {
+    findLocalTool: function(toolName: string, version: string) {
+        console.log('Found cached Go version');
+        return '/mock/cache/go/1.8.7';
+    },
+    prependPath: function(toolPath: string) {
+        console.log(`Adding to PATH: ${toolPath}`);
+    }
+});
+
+// Mock os module
+tmr.registerMock('os', {
+    platform: () => 'linux',
+    arch: () => 'x64'
+});
+
+// Mock telemetry
+tmr.registerMock('azure-pipelines-tasks-utility-common/telemetry', {
+    emitTelemetry: function(area: string, feature: string, properties: any) {
+        console.log(`Telemetry: ${area}.${feature}`);
+    }
+});
+
+tmr.run();

Tasks/GoToolV0/Tests/L0GorootModernVersion.ts

@@ -0,0 +1,37 @@
+import tmrm = require('azure-pipelines-task-lib/mock-run');
+import path = require('path');
+
+let taskPath = path.join(__dirname, '..', 'gotool.js');
+let tmr: tmrm.TaskMockRunner = new tmrm.TaskMockRunner(taskPath);
+
+// Test modern Go version (>= 1.9) - GOROOT should NOT be set
+tmr.setInput('version', '1.23.3');
+
+// Mock environment variables
+process.env['Agent.TempDirectory'] = path.join(__dirname, 'temp');
+
+// Mock tool lib functions
+tmr.registerMock('azure-pipelines-tool-lib/tool', {
+    findLocalTool: function(toolName: string, version: string) {
+        console.log('Found cached Go version');
+        return '/mock/cache/go/1.23.3';
+    },
+    prependPath: function(toolPath: string) {
+        console.log(`Adding to PATH: ${toolPath}`);
+    }
+});
+
+// Mock os module
+tmr.registerMock('os', {
+    platform: () => 'linux',
+    arch: () => 'x64'
+});
+
+// Mock telemetry
+tmr.registerMock('azure-pipelines-tasks-utility-common/telemetry', {
+    emitTelemetry: function(area: string, feature: string, properties: any) {
+        console.log(`Telemetry: ${area}.${feature}`);
+    }
+});
+
+tmr.run();

Tasks/GoToolV0/gotool.ts

@@ -65,7 +65,7 @@ async function getGo(version: string, baseUrl?: string): Promise<string> {
         tl.debug("Go tool is available under " + toolPath);
     }
 
-    setGoEnvironmentVariables(toolPath);
+    setGoEnvironmentVariables(toolPath, resolved.filenameVersion);
     const binPath = path.join(toolPath, 'bin');
     toolLib.prependPath(binPath);
     return resolved.filenameVersion;
@@ -126,8 +126,18 @@ function getDownloadUrl(filename: string, baseUrl?: string): string {
     return `${base.replace(/\/+$/, '')}/${filename}`;
 }
 
-function setGoEnvironmentVariables(goRoot: string): void {
-    tl.setVariable('GOROOT', goRoot);
+function setGoEnvironmentVariables(goRoot: string, version: string): void {
+    // Only set GOROOT for Go < 1.9; modern versions auto-detect it.
+    // Setting it explicitly breaks custom builds (e.g., Go tip). See: #20796
+    const parsed = parseGoVersion(version);
+
+    if (parsed.major < 1 || (parsed.major === 1 && parsed.minor < 9)) {
+        tl.debug('Setting GOROOT for Go version < 1.9');
+        tl.setVariable('GOROOT', goRoot);
+    } else {
+        tl.debug('Skipping GOROOT for modern Go version (>= 1.9)');
+    }
+
     const goPath = tl.getInput("goPath", false);
     const goBin = tl.getInput("goBin", false);
     if (goPath) {

Tasks/GoToolV0/task.json

@@ -13,7 +13,7 @@
   "author": "Microsoft Corporation",
   "version": {
     "Major": 0,
-    "Minor": 265,
+    "Minor": 268,
     "Patch": 0
   },
   "satisfies": [

Tasks/GoToolV0/task.loc.json

@@ -13,7 +13,7 @@
   "author": "Microsoft Corporation",
   "version": {
     "Major": 0,
-    "Minor": 265,
+    "Minor": 268,
     "Patch": 0
   },
   "satisfies": [