diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3119167..ea51fc3 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,10 +6,10 @@ jobs:
     runs-on: ubuntu-20.04
 
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-go@v2
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v4
         with:
-          go-version: "1.17"
+          go-version: "1.20"
       - uses: actions/setup-node@v2
         with:
           node-version: ^18
@@ -30,13 +30,13 @@ jobs:
           'stable',
           'insiders'
         ]
-        os: [macos-10.15, ubuntu-20.04, windows-2019]
+        os: [macos-12, ubuntu-20.04]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
-      - uses: actions/setup-go@v2
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v4
         with:
-          go-version: "1.17"
+          go-version: "1.20"
       - uses: actions/setup-node@v2
         with:
           node-version: ^18
diff --git a/src/extension.ts b/src/extension.ts
index 625e72b..9e48ca7 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-import * as path from 'path';
-
 import { 
 	workspace, 
 	ExtensionContext, 
diff --git a/src/test/lint.test.ts b/src/test/lint.test.ts
index 1ce3ef0..a09ae9a 100644
--- a/src/test/lint.test.ts
+++ b/src/test/lint.test.ts
@@ -33,8 +33,8 @@ suite('Should report diagnostics for the invalid fixtures', () => {
 		{
 			name: "invalid/multiple-tm-config-git/tm2.tm",
 			diags: [new vscode.Diagnostic(
-				range(begin(2, 8), end(2, 13)),
-				'multiple terramate.config.git blocks',
+				range(begin(3, 12), end(3, 26)),
+				'terramate schema error: attribute "default_branch" redeclared in file',
 				vscode.DiagnosticSeverity.Error
 			)]
 		},
@@ -42,8 +42,9 @@ suite('Should report diagnostics for the invalid fixtures', () => {
 
 	testcases.forEach((tc) => {
 		const testFixture = getDocPath(tc.name);
-		test('lint file: '+testFixture, async () => {
-			await testLint(vscode.Uri.file(testFixture), tc.diags);
+		const file = vscode.Uri.file(testFixture);
+		test('lint file: '+file, async () => {
+			await testLint(file, tc.diags);
 		});
 	});
 });
@@ -59,17 +60,17 @@ suite('Should not report diagnostics for the valid files', () => {
 		const filents = fs.readdirSync(dir, {withFileTypes: true});
 		const fileNames = filents.
 			filter(filent => filent.isFile()).
-			map(filent => path.resolve(dir, filent.name));
+			map(filent => path.resolve(dir, filent.name)).
+			sort();
 		if (fileNames.length == 0) {
 			return;
 		}
 
 		// we chose one file to report diagnostics but other files in the
 		// directory will be also checked.
-		const file = fileNames[0]; 
-
+		const file = vscode.Uri.file(path.resolve(testDir, fileNames[0]));
 		test('test file: '+file, async () => {
-			await testLint(vscode.Uri.file(path.resolve(testDir, file)), []);
+			await testLint(file, []);
 		});
 	});	
 });
diff --git a/testFixture/invalid/multiple-tm-config-git/tm1.tm b/testFixture/invalid/multiple-tm-config-git/tm1.tm
index e13dbd2..c5efc72 100644
--- a/testFixture/invalid/multiple-tm-config-git/tm1.tm
+++ b/testFixture/invalid/multiple-tm-config-git/tm1.tm
@@ -1,7 +1,7 @@
 terramate {
     config {
         git {
-
+            default_branch = "main"
         }
     }
 }
diff --git a/testFixture/invalid/multiple-tm-config-git/tm2.tm b/testFixture/invalid/multiple-tm-config-git/tm2.tm
index e13dbd2..6c7cb06 100644
--- a/testFixture/invalid/multiple-tm-config-git/tm2.tm
+++ b/testFixture/invalid/multiple-tm-config-git/tm2.tm
@@ -1,7 +1,7 @@
 terramate {
     config {
         git {
-
+            default_branch = "trunk"
         }
     }
 }
diff --git a/testFixture/tmfiles/rootcfg/terramate.tm.hcl b/testFixture/tmfiles/rootcfg/terramate.tm
similarity index 100%
rename from testFixture/tmfiles/rootcfg/terramate.tm.hcl
rename to testFixture/tmfiles/rootcfg/terramate.tm