src/gobang.go: Add WrapErrors()

1 files changed, 29 insertions, 0 deletions

diff --git a/tests/gobang.go b/tests/gobang.go
index be33eb4..9d42ca9 100644
--- a/tests/gobang.go
+++ b/tests/gobang.go
@@ -3,6 +3,7 @@ package gobang
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 	"log/slog"
 	"os"
 	"strings"
@@ -48,6 +49,32 @@ func test_ValidateSQLTablePrefix() {
 	})
 }
 
+func test_WrapErrors() {
+	TestStart("WrapErrors()")
+
+	Testing("nil for empty args", func() {
+		TAssertEqual(WrapErrors(), nil)
+	})
+
+	Testing("nil when all args are nil", func() {
+		TAssertEqual(WrapErrors(nil, nil, nil), nil)
+	})
+
+	Testing("if only 1 is an error, return it", func() {
+		err := errors.New("my error")
+		TAssertEqual(WrapErrors(nil, nil, err), err)
+	})
+
+	Testing("otherwise wrap them, from right to left", func() {
+		err1 := errors.New("error 1")
+		err2 := errors.New("error 2")
+		expected1 := fmt.Errorf("error %w on top of %w", err1, err2)
+		expected2 := fmt.Errorf("error %w on top of %w", err2, err1)
+		TAssertEqual(WrapErrors(nil, err1, nil, err2), expected1)
+		TAssertEqual(WrapErrors(err2, nil, nil, err1), expected2)
+	})
+}
+
 func test_SomeError() {
 	TestStart("SomeError()")
 
@@ -763,8 +790,10 @@ func test_setHostname() {
 }
 
 
+
 func MainTest() {
 	test_ValidateSQLTablePrefix()
+	test_WrapErrors()
 	test_SomeError()
 	test_SomeFnError()
 	test_Random()