Add gometalinter test case

.travis.yml

@@ -26,6 +26,8 @@ install:
   - go get -u -v github.com/lukehoban/go-outline
   - go get -u -v sourcegraph.com/sqs/goreturns
   - go get -u -v golang.org/x/tools/cmd/gorename
+  - go get -u -v github.com/alecthomas/gometalinter
+  - gometalinter --install --update
 
 script:
   - npm run lint

test/go.test.ts

@@ -116,4 +116,35 @@ suite('Go Extension Tests', () => {
 			assert.equal(sortedDiagnostics.length, expected.length, `too many errors ${JSON.stringify(sortedDiagnostics)}`);
 		}).then(() => done(), done);
 	});
+
+	test('Gometalinter error checking', (done) => {
+		let config = vscode.workspace.getConfiguration('go');
+		config['lintTool'] = 'gometalinter';
+		let expected = [
+			{ line: 7, severity: 'warning', msg: 'Print2 is unused (deadcode)' },
+			{ line: 7, severity: 'warning', msg: 'exported function Print2 should have comment or be unexported (golint)' },
+			{ line: 10, severity: 'warning', msg: 'main2 is unused (deadcode)' },
+			{ line: 11, severity: 'warning', msg: 'undeclared name: prin (aligncheck)' },
+			{ line: 11, severity: 'warning', msg: 'undeclared name: prin (gotype)' },
+			{ line: 11, severity: 'warning', msg: 'undeclared name: prin (interfacer)' },
+			{ line: 11, severity: 'warning', msg: 'undeclared name: prin (unconvert)' },
+			{ line: 11, severity: 'error', msg: 'undefined: prin' },
+			{ line: 11, severity: 'warning', msg: 'unused struct field undeclared name: prin (structcheck)' },
+		];
+		check(path.join(fixturePath, 'errors.go'), config).then(diagnostics => {
+			let sortedDiagnostics = diagnostics.sort((a, b) => {
+				if ( a.msg < b.msg )
+					return -1;
+				if ( a.msg > b.msg )
+					return 1;
+				return 0;
+			});
+			for (let i in expected) {
+				assert.equal(sortedDiagnostics[i].line, expected[i].line);
+				assert.equal(sortedDiagnostics[i].severity, expected[i].severity);
+				assert.equal(sortedDiagnostics[i].msg, expected[i].msg);
+			}
+			assert.equal(sortedDiagnostics.length, expected.length, `too many errors ${JSON.stringify(sortedDiagnostics)}`);
+		}).then(() => done(), done);
+	});
 });