From 351b5bcfef2bf0ae147fa6c77c471a43de685b98 Mon Sep 17 00:00:00 2001
From: Ashish Ranjan <ashishranjan738@gmail.com>
Date: Fri, 25 Jan 2019 12:44:16 +0530
Subject: [PATCH] Adds UT for trace package in utils

Signed-off-by: Ashish Ranjan <ashishranjan738@gmail.com>

This PR adds UT for trace package in utils repository
---
 trace/trace_test.go | 200 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 200 insertions(+)
 create mode 100644 trace/trace_test.go

diff --git a/trace/trace_test.go b/trace/trace_test.go
new file mode 100644
index 00000000..9b61bb40
--- /dev/null
+++ b/trace/trace_test.go
@@ -0,0 +1,200 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package trace
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+	"time"
+
+	"k8s.io/klog"
+)
+
+func TestStep(t *testing.T) {
+	tests := []struct {
+		name          string
+		inputString   string
+		expectedTrace *Trace
+	}{
+		{
+			name:        "When string is empty",
+			inputString: "",
+			expectedTrace: &Trace{
+				steps: []traceStep{
+					{time.Now(), ""},
+				},
+			},
+		},
+		{
+			name:        "When string is not empty",
+			inputString: "test2",
+			expectedTrace: &Trace{
+				steps: []traceStep{
+					{time.Now(), "test2"},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			sampleTrace := &Trace{}
+			sampleTrace.Step(tt.inputString)
+			if sampleTrace.steps[0].msg != tt.expectedTrace.steps[0].msg {
+				t.Errorf("Expected %v \n Got %v \n", tt.expectedTrace, sampleTrace)
+			}
+		})
+	}
+}
+
+func TestTotalTime(t *testing.T) {
+	test := struct {
+		name       string
+		inputTrace *Trace
+	}{
+		name: "Test with current system time",
+		inputTrace: &Trace{
+			startTime: time.Now(),
+		},
+	}
+
+	t.Run(test.name, func(t *testing.T) {
+		got := test.inputTrace.TotalTime()
+		if got == 0 {
+			t.Errorf("Expected total time 0, got %d \n", got)
+		}
+	})
+}
+
+func TestLog(t *testing.T) {
+	test := struct {
+		name             string
+		expectedMessages []string
+		sampleTrace      *Trace
+	}{
+		name: "Check the log dump with 3 msg",
+		expectedMessages: []string{
+			"msg1", "msg2", "msg3",
+		},
+		sampleTrace: &Trace{
+			name: "Sample Trace",
+			steps: []traceStep{
+				{time.Now(), "msg1"},
+				{time.Now(), "msg2"},
+				{time.Now(), "msg3"},
+			},
+		},
+	}
+
+	t.Run(test.name, func(t *testing.T) {
+		var buf bytes.Buffer
+		klog.SetOutput(&buf)
+		test.sampleTrace.Log()
+		for _, msg := range test.expectedMessages {
+			if !strings.Contains(buf.String(), msg) {
+				t.Errorf("\nMsg %q not found in log: \n%v\n", msg, buf.String())
+			}
+		}
+	})
+}
+
+func TestLogIfLong(t *testing.T) {
+	currentTime := time.Now()
+	type mutate struct {
+		delay time.Duration
+		msg   string
+	}
+
+	tests := []*struct {
+		name             string
+		expectedMessages []string
+		sampleTrace      *Trace
+		threshold        time.Duration
+		mutateInfo       []mutate // mutateInfo contains the information to mutate step's time to simulate multiple tests without waiting.
+
+	}{
+		{
+			name: "When threshold is 500 and msg 2 has highest share",
+			expectedMessages: []string{
+				"msg2",
+			},
+			mutateInfo: []mutate{
+				{10, "msg1"},
+				{1000, "msg2"},
+				{0, "msg3"},
+			},
+			threshold: 500,
+		},
+		{
+			name: "When threshold is 10 and msg 3 has highest share",
+			expectedMessages: []string{
+				"msg3",
+			},
+			mutateInfo: []mutate{
+				{0, "msg1"},
+				{0, "msg2"},
+				{50, "msg3"},
+			},
+			threshold: 10,
+		},
+		{
+			name: "When threshold is 0 and all msg have same share",
+			expectedMessages: []string{
+				"msg1", "msg2", "msg3",
+			},
+			mutateInfo: []mutate{
+				{0, "msg1"},
+				{0, "msg2"},
+				{0, "msg3"},
+			},
+			threshold: 0,
+		},
+		{
+			name:             "When threshold is 20 and all msg 1 has highest share",
+			expectedMessages: []string{},
+			mutateInfo: []mutate{
+				{10, "msg1"},
+				{0, "msg2"},
+				{0, "msg3"},
+			},
+			threshold: 20,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			klog.SetOutput(&buf)
+
+			tt.sampleTrace = New("Test trace")
+
+			for index, mod := range tt.mutateInfo {
+				tt.sampleTrace.Step(mod.msg)
+				tt.sampleTrace.steps[index].stepTime = currentTime.Add(mod.delay)
+			}
+
+			tt.sampleTrace.LogIfLong(tt.threshold)
+
+			for _, msg := range tt.expectedMessages {
+				if msg != "" && !strings.Contains(buf.String(), msg) {
+					t.Errorf("Msg %q expected in trace log: \n%v\n", msg, buf.String())
+				}
+			}
+		})
+	}
+}