From 88bcdb254d548c0c8d0c19001062de3ac9d73fbb Mon Sep 17 00:00:00 2001
From: Simone Basso <bassosimone@gmail.com>
Date: Mon, 27 Sep 2021 14:55:47 +0200
Subject: [PATCH] feat(errorsx): introduce NewTopLevelGenericErrWrapper (#511)

Part of https://github.com/ooni/probe/issues/1733 and diff has been
extracted from https://github.com/ooni/probe-cli/pull/506.
---
 internal/netxlite/errorsx/errwrapper.go      |  6 ++++++
 internal/netxlite/errorsx/errwrapper_test.go | 16 ++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/internal/netxlite/errorsx/errwrapper.go b/internal/netxlite/errorsx/errwrapper.go
index 81c3ac2bba..a814b6eaeb 100644
--- a/internal/netxlite/errorsx/errwrapper.go
+++ b/internal/netxlite/errorsx/errwrapper.go
@@ -92,3 +92,9 @@ func NewErrWrapper(c Classifier, op string, err error) *ErrWrapper {
 		WrappedErr: err,
 	}
 }
+
+// NewTopLevelGenericErrWrapper wraps an error occurring at top
+// level using the most generic available classifier.
+func NewTopLevelGenericErrWrapper(err error) *ErrWrapper {
+	return NewErrWrapper(ClassifyGenericError, TopLevelOperation, err)
+}
diff --git a/internal/netxlite/errorsx/errwrapper_test.go b/internal/netxlite/errorsx/errwrapper_test.go
index d7986b82c7..68a643778a 100644
--- a/internal/netxlite/errorsx/errwrapper_test.go
+++ b/internal/netxlite/errorsx/errwrapper_test.go
@@ -102,3 +102,19 @@ func TestNewErrWrapper(t *testing.T) {
 		}
 	})
 }
+
+func TestNewTopLevelGenericErrWrapper(t *testing.T) {
+	out := NewTopLevelGenericErrWrapper(io.EOF)
+	if out.Failure != FailureEOFError {
+		t.Fatal("invalid failure")
+	}
+	if out.Operation != TopLevelOperation {
+		t.Fatal("invalid operation")
+	}
+	if !errors.Is(out, io.EOF) {
+		t.Fatal("invalid underlying error using errors.Is")
+	}
+	if !errors.Is(out.WrappedErr, io.EOF) {
+		t.Fatal("invalid WrappedErr")
+	}
+}