refactoring tests util methods + adding context tests

test/xerror.go

@@ -0,0 +1,18 @@
+package test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xerror"
+)
+
+// AssertError validates that given error
+// is of an instance of xerror.Error.
+// If so, returns the instance of xerror.Error.
+func AssertError(t *testing.T, err error) *xerror.Error {
+	assert.NotNil(t, err)
+	standardized, ok := err.(*xerror.Error)
+	assert.Equal(t, true, ok)
+	return standardized
+}