From cdf856f0ab8be13e8dff0296bfa9bb2a677ce815 Mon Sep 17 00:00:00 2001
From: lysu <sulifx@gmail.com>
Date: Wed, 15 May 2019 13:36:41 +0800
Subject: [PATCH] add NewNoStackError support (#13)

---
 juju_adaptor.go | 11 +++++++++++
 stack_test.go   | 10 ++++++++++
 2 files changed, 21 insertions(+)

diff --git a/juju_adaptor.go b/juju_adaptor.go
index 215b4b5..7abb262 100644
--- a/juju_adaptor.go
+++ b/juju_adaptor.go
@@ -55,6 +55,17 @@ func Annotatef(err error, format string, args ...interface{}) error {
 	}
 }
 
+var emptyStack stack
+
+// NewNoStackError creates error without error stack
+// later duplicate trace will no longer generate Stack too.
+func NewNoStackError(msg string) error {
+	return &fundamental{
+		msg:   msg,
+		stack: &emptyStack,
+	}
+}
+
 // ErrorStack will format a stack trace if it is available, otherwise it will be Error()
 // If the error is nil, the empty string is returned
 // Note that this just calls fmt.Sprintf("%+v", err)
diff --git a/stack_test.go b/stack_test.go
index 5603425..cf9efad 100644
--- a/stack_test.go
+++ b/stack_test.go
@@ -287,3 +287,13 @@ func TestNewStack(t *testing.T) {
 		t.Errorf("NewStack(): want: %v, got: %+v", "testing.tRunner", gotFirst)
 	}
 }
+
+func TestSuspendStackError(t *testing.T) {
+	err := NewNoStackError("test error")
+	err = Trace(err)
+	err = Trace(err)
+	result := fmt.Sprintf("%+v", err)
+	if result != "test error" {
+		t.Errorf("NewNoStackError(): want %s, got %v", "test error", result)
+	}
+}