Added integration test

internal/integrationtest/compile_3/compile_cxx_cc_test.go

@@ -0,0 +1,42 @@
+// This file is part of arduino-cli.
+//
+// Copyright 2022 ARDUINO SA (http://www.arduino.cc/)
+//
+// This software is released under the GNU General Public License version 3,
+// which covers the main part of arduino-cli.
+// The terms of this license can be found at:
+// https://www.gnu.org/licenses/gpl-3.0.en.html
+//
+// You can be released from the requirements of the above licenses by purchasing
+// a commercial license. Buying such a license is mandatory if you want to
+// modify or otherwise use the software for commercial activities involving the
+// Arduino software without disclosing the source code of your own applications.
+// To purchase a commercial license, send an email to [email protected].
+
+package compile_test
+
+import (
+	"testing"
+
+	"github.com/arduino/arduino-cli/internal/integrationtest"
+	"github.com/arduino/go-paths-helper"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCompileSketchWithCxxOrCc(t *testing.T) {
+	// See: https://github.com/arduino/arduino-cli/issues/1149
+
+	env, cli := integrationtest.CreateArduinoCLIWithEnvironment(t)
+	defer env.CleanUp()
+
+	// Run update-index with our test index
+	_, _, err := cli.Run("core", "install", "arduino:[email protected]")
+	require.NoError(t, err)
+
+	// Prepare sketchbook and sketch
+	sketch, err := paths.New("testdata", "sketch_with_cxx_cc").Abs()
+	require.NoError(t, err)
+
+	_, _, err = cli.Run("compile", "-v", "-b", "arduino:avr:uno", sketch.String())
+	require.NoError(t, err)
+}

internal/integrationtest/compile_3/testdata/sketch_with_cxx_cc/sketch_with_cxx_cc.ino

@@ -0,0 +1,11 @@
+void func_in_cc();
+void func_in_cxx();
+
+void setup() {
+    func_in_cc();
+    func_in_cxx();
+}
+
+void loop() {
+
+}

internal/integrationtest/compile_3/testdata/sketch_with_cxx_cc/test.cc

@@ -0,0 +1,3 @@
+void func_in_cc() {
+
+}

internal/integrationtest/compile_3/testdata/sketch_with_cxx_cc/test.cxx

@@ -0,0 +1,3 @@
+void func_in_cxx() {
+
+}