Added integration test

Author: cmaglie

Diff for: internal/integrationtest/compile_4/lib_caching_test.go

@@ -0,0 +1,45 @@
+package compile
+
+import (
+	"testing"
+
+	"github.com/arduino/arduino-cli/internal/integrationtest"
+	"github.com/arduino/go-paths-helper"
+	"github.com/stretchr/testify/require"
+)
+
+func TestBuildCacheLibWithNonASCIIChars(t *testing.T) {
+	// See: https://github.com/arduino/arduino-cli/issues/2671
+
+	env, cli := integrationtest.CreateArduinoCLIWithEnvironment(t)
+	t.Cleanup(env.CleanUp)
+
+	tmpUserDir, err := paths.MkTempDir("", "Håkan")
+	require.NoError(t, err)
+	t.Cleanup(func() { tmpUserDir.RemoveAll() })
+	customEnv := cli.GetDefaultEnv()
+	customEnv["ARDUINO_DIRECTORIES_USER"] = tmpUserDir.String()
+
+	// Install Arduino AVR Boards and Servo lib
+	_, _, err = cli.Run("core", "install", "arduino:[email protected]")
+	require.NoError(t, err)
+	_, _, err = cli.RunWithCustomEnv(customEnv, "lib", "install", "Servo")
+	require.NoError(t, err)
+
+	// Make a temp sketch
+	sketchDir := tmpUserDir.Join("ServoSketch")
+	sketchFile := sketchDir.Join("ServoSketch.ino")
+	require.NoError(t, sketchDir.Mkdir())
+	require.NoError(t, sketchFile.WriteFile(
+		[]byte("#include <Servo.h>\nvoid setup() {}\nvoid loop() {}\n"),
+	))
+
+	// Compile sketch
+	_, _, err = cli.RunWithCustomEnv(customEnv, "compile", "-b", "arduino:avr:uno", sketchFile.String())
+	require.NoError(t, err)
+
+	// Compile sketch again
+	out, _, err := cli.RunWithCustomEnv(customEnv, "compile", "-b", "arduino:avr:uno", "-v", sketchFile.String())
+	require.NoError(t, err)
+	require.Contains(t, string(out), "Compiling library \"Servo\"\nUsing previously compiled file")
+}