fix: fix bugs in test

cryptor/rsa_private_example.pem

@@ -1,51 +1,51 @@
 -----BEGIN rsa private key-----
-MIIJKQIBAAKCAgEAtKEukXkdl8ggX5I5Us0MBcsrFzbTgwOn8u72IhJzruvsHcjl
+MIIJKQIBAAKCAgEAtXr+2FbR6Prdf9U0gfq2OJbTD82m84bbdeyfsakabYp8Haw6
-GGF5L1eXh3C0zbcoWq+Bxf8NnXvSXASZlZHTiSVLFerxFw2LwTNcyfOz/Y/wIbtr
+mZW6ebRNPJvQ87H6DbA55hK1E7y6m+wjvbUopnkGh75Cp04CoQvaU8Rs7MrQcJ2Z
-Yu4ZdttLKdJS607UvnZ57O7SQni5rxYAP5j+veKHEJgAO7Sn0lEEWwkeudsfVrQm
+z1VRRgugmqwJMWE/FC5eGXvvpDjF2h2lqThKZTKcvhqfZ3dNX+6v4EQ4BbjSGKdz
-Qx6JHYtCtx78p2GHXPj9wXWHxWHKMkczKtmBFDLlYocPhQfWzx87sYKjGmTMGzVd
+pyexzR1WSV9IzZYRHMk8jCoEHOx9ItEzoToBf9yAq0DhufylqSRbjKLhR7A3IiRS
-dsrllAqVozlxXTQndOdozx8BWHSBiYWguOvWiYjvryrIf0B7wn4wt3o2Yre3w4Bk
+LVNfu0Sz5cfNlS7eUA060QS8AV9BgGNTkl75aj8BCOmoHIW85SsSZvdQWYwmlM76
-wrTUE73JWG2q1NLuPoT27m7WcdVFGGcKAygAdMMSwS530v8tnAw876/w1SfUmtkI
+Jn+tfNNnY7Uuqtz2gI1odcy1nXembXWJryxuYCkSAwpU8UNIQpZeKwBnBxaf0pj3
-cqknysMjsvxHx1fbEfkl3b0yBnzcUrT1qxzmNEqJSQXBtFYFyGgyeL8J1ul/T5hP
+W1m3UzEqhGkkCrKq8LkNSGZSkhT+bI65fNx2LZ7lS165szkeyqS8aikxcBpdx7Z/
-SNz0we5TO/xRkX5Y1HNJ+a2r8EnE1PU8zgQGBxYSIub4ajSUccyn5yHQ/k2Flsol
+bqbFFuI42KX+IpXAJCAtvsQ0XXinr83MLcY/I2Ic/5Sgz7txfZsKKwKt48ETS9Bj
-Ziu/UzfnzMgdg55svgf5x1ntKYBoVHuYe84Ab3WRAeVlUi0OphvFlBzfIQvrG2sR
+xGPWo1Dd5YjM8ZJWJv2Rf0mwVjUMClFSNBm8x+aWGVIKjpocN/plpEZmFrWdPcWM
-biPZRZZ0E8kBH94zPmrFmyX+7TwlSqVHtNFc+Ynz+hrHcd4z6N7fIb+D1gSYuukk
+4ZH3qGCEnVVkqPvqClahNSQXsM4W7msYts1IUq31tjBSV5bL6l2K8jFJa4PRYdzh
-cRqr4ANO0ugZk0YYKaWDf86H7OZOXna8ObIAi+3gx+Wcp1lm7Ffk9sn+dGkCAwEA
+1vHhDOAYTpgDkQbNaoDlDS2o/0TkAGUfXWJtR3D35wRJzoa7bCMt5BuFE3sCAwEA
-AQKCAgAdp/kFWWVKbkkiZ9eRiKjYqqrAfPftIsSIVkODBJSJu6JgoYM7pYVICJGQ
+AQKCAgEAm/OsGEDTdcBOo9GVo7TM7mg9y7DQLSnQYdALk2JcAZImAmHEocLXUkqs
-YyjMPa4adYZRA7cwjAvVn8u3iuG4Oq9BQfmjV04CwnQRlDmQ//jlEOhorb7wjMCi
+rM7BiwmAdk7gEmQ1E1b1jZQpSpbo7dXG1NOc96TEAZzr61w6tmm7IWtth4wroWPQ
-dS24BJFZVApgpDVRRJD39hzEVFI+ytpyFwKyys5i8XpNmAm7agaTLbC6hGDuwNaL
+idoYtER7Ll6CIqgsURUwgLVFbNugosIRjBPYs9MDvNKidLhq5A/lC6aqbhRgaIEz
-SkMhGBopYZgIE0vfVFbmOlpkRqGyt0iCDLq3lLnn97DNTC2LP9FjBjf6MQXQcIxw
+ay3kpDa3UeNkkpZwnmJjTo40LfJo43WbZI8G6wq/WVCTE5HMwgwd9Mr9i1HATG9H
-6BV8v/tabkP+/ZAy/a3m7lGdCtuGaT0w/U0911B6dk15Uk9rlc5OAt6IOTg4pYhR
+oMhIVFDIXkZgKspEvXEcGrZAVOIktzaZLw2Ll6cdolmXIMCaXblgVjRfJsJFVaVd
-RHAv0RHcoegI7Zm3xtQ5VXGHYyHvwwXA/e5pAqOOO/GZ+85OcilphnSLGoP71rqJ
+jYNfLRlhAyuBfumBkGYHsLx2qwAlgC1gCY/72RAtpQWTsefNp9Athztj7iAbwW67
-h22GXTj4uCWiiPA8yLwAdtLKhN/KygzH3gkrsD5bH5R9ZmnBiIk192X2v1flND8M
+AgWlz44TOxtp2JTZOQZs9Douunp+DNFzA30bJasyWD+EZcUdyxMWhW27b2EQFfjP
-ikBx6ADCphQnJ2zhCv6teesro9A0GIHVI0NjpZayvKjHMHpMpHpN8ZLMTmbafIH3
+XefmjJKkfTuG4f/Oti+Qqy6qnd/L22iph6WuAzSBCUAdkyHwvFwK32H971aNLqlA
-tq3g9H17ncWal2qDKco7J+6VgJx1NRGlQY/52J25BX2UzB3rrFW21w01TCtpKH3d
+nBUn9/CYZ9m4oiR2bqide4B2P3/3wzFyLTHZqwaJDBnHV4nVUy+CxGsbhIyXLyCq
-o4sPl5IQS5RsrlPEIVAOo7tYHsB5pgfWUzMN3u9hONnES4NHwgDgYJlRl9B/unPh
+csmWaP9VUKCgIlI1B7MY5puHaYULKWnVye8+ges363ndvGEtdvke/9qkyNgc2Kxi
-/kbz/lEJq3Cw2F3zhYb/8neM49lgmWq+hpUshejiYABaXpMGoQKCAQEA4audTQEt
+ZNKIzZWihoBa1pPqqsSEm99L70TpXfdca6M3+2teLm63dk0cPpECggEBAOm52TD2
-cH89v7NGWWUplfIgb2ndXUW8IrJQbuLbFkCdlXbSfsOA6GsA8bMNI9IUqAfCpvNg
+l3waYVyh85IJZo9fgtemlOJ7vSzEWivscYzqwzY+xfQuvj4lFOxHno/wu0lORD3a
-qmCdJ7b8kfHDIilW2SPDA9wW3Fd30ofJEIkfRet87DeT541E27hUHTZ5GSiKvzqn
+1xzC9v+OBvIKpX5PQ9bbS+Oe94kZMZmtF4oyPpvmPbSIhZvASWq/oaMSpq9RIINW
-j+IXu2mpcASgeOJnIp6KmyTOIwj9DJZPexnDRYwnbjpLUdWCCkGcXbIMggrvjaTj
+13o91q37leXCj3XhEmqWbStbMwJ7aRU45K7qKbMMM9EmsageBykoyy3PfHFZvsAh
-QEWW8RWt+GPyhDACh1KFa2RSON5p3HasPKZJmJz6Zgk9rJ7xI3MSdnGjGMl4PviB
+joQWRCFSmso94YBrpT0rZj9t57y3j9zrCTc+5T0OXkA69yhKrkwL6JQowMHbisx9
-LyrXjf5URqrDmpUf+Xtl3ysNiGDzRBn05SjpmsS2yOjQlK5CiK/o+LTIsNUtdzay
+p+c4467vdwAaDx14/EYERkqiNjxWS1zCfenTvBs7Gu+/C+/4gZnt2I8vbsTf9wyP
-5PLoxR74b6uTtwKCAQEAzOfmshWZ7AbaaLYPCdV3aDRsti4O8U400cc4QFTMBjwZ
+g2Hg/V/txAGreF8CggEBAMbGhtowf7TgFvn3T9fmFEBaCIe+m888hkTamiGLUrDh
-AI8A/++fcTZJgtmFPMhg4C9BNj1w8sgcQ7otTv5iJFgZ2bktBp5dgWsX4SbyrC16
+HCTO34vHMo/5Tds3Fy1c/BPvECV3wv/Nln046MuMuLIkIbk3uhVmVEFKGKMlqq6H
-xapOa1PNcgV+YmZ2HnzC4lCfE42hsTP2QI2E2Yr1vyeZ9YvbWJHvBJYA0s5lwkpp
+KRd+PErAf59FQ3Yfkqm7/JnBPgdvgzPmc09SAafHgiogMuu4FFDob+LSENuZl0zA
-dO7abJ/F6DYzpvjomAobutTQmd0XvNTSLuhfudRDadC4RtBQ/bjF+Rx3EjXeWJzy
+U6Xr9nQphB4IxG15dVSEDKQhlhcTGQy0VBx6sskg6897MuJduDJiNPjQpWmGDuji
-l83VBsDnlqhrsGpV+yq1pRePfY9XzDjWfz+oOzCMSvl1+eXmFxl7PJqXc9JD2CeW
+9xuNURVy4FuHYr9yUEDBwWkL8VjKwzASDgK0b38knUpThP33W/TZgQWewFfSD6Nq
-6xfzQEXxB7czHaTJ4tSB4yC7U9qOXLkZQBpyGg143wKCAQA9raH4gfHhZWWDF4SK
+fBBmct7JYfLNEwItlr/NOF9Q+KIeB9E3Ok+xO99BKmUCggEAbBWg5e6zQRXl/nN6
-ulN7YAntaYnPDFg3Q3UoWWh31IE9cJRngReiblx7suxMdgafRj+1UZ+B8ZYCXMj7
+cwdb4WOW22lSoqX8Zs5qsLNIE5WhLt26p2BSY+S8F0RLhF8cDRtfnYctQUS7+pRQ
-OpCSranG/zc1vtmgr2dYazRRCKk7evlRtn7+MmY3h1G2CkVe0u3ZBjb15F2II4Dj
+i+/2dkHrqlmBb8Lc0A7RjDKqlyMDJw9Da9BSkSNMEEyMUCBY6uxGb9ZiEUq1k4Gr
-1N/nKjn2BE7tyElu2e4PmqVuh8QPJhdA0T30x94a34PVN+yjPknq9L4Huv1eNwat
+4TOnKikqXhYwaANlxHkTsFe+EVGCdSVodQlC0O8J+rO9ufKgpr6M4sbh5B1z5kEQ
-dOO7rUODqNI+X9T5JhDY6LZ6fRhwVbc6XBw3KdnOTo0lQjnJdIcg7tqgAZ2YeYKf
+CgSx2rRtFquSPjTyHKh6o/whJ+YzFpglZ+ic0YovrkU3igSKl1uShVx6oAgD6qsc
-Ldz4SvnKPifBrwqr05OpcU61s1DltA4hK0CW4mnc4fdSwlZ3vkwG4TRTzvA/sA9G
+yfRDFysS5sIlS3BWSnLRqRTcK5zZ+XHM1B/yQkgWjvuZ0SVrQSodUjav2Dy2j30h
-tiZRAoIBAQCuVmCiBF8BwpLxpHUHGOiPcItONcHg7XljQu1JTtyIMXnUT9e56lbu
+zm/gWwKCAQBXUun1Oq8vz+5oG/zIlTw6VRNARz192lIGN57Us7c9G3fYt8U/S+Br
-LBI/knMaVCKYm5wQWhZPepMRzMXf/+/gnFTiOftlNji4dDXNCyZN+CQNKemux451
+nZNVhas584qOW0zVmPpilHfTRUgH/Cc7o2HpU5D9S7oiAKI4Mhj8mUY1GvDzygOG
-BNeTQToelmf5xj6SlF6ONne+VKpDrUeJbFhB4sytfvyuGjJ5KcLKnCU9qDuPUCFC
+/c+4OgCdbod3KIzOiW+zQj9QDm/JvHzzcrfMFE9gh+x3Ud+0CZKNVkSpNLNNrttq
-gVtRJVZAhdkyDP+u6b3Ym/p4jp1jroXs8fjXx0YhmaRXXzCv/cU//8kn/6jQJjDk
+smFQ0rX3zhcbl+Gu+2XazfHRnRmkAEF4IeBlz9RW1gv9bvPsGse8CdGTGg8QBCqK
-rkdxwgeFu8Dwxir/2YYJ7BIUEkVAlv3GjJkkFca+wJ9p4N4bXTr8HjL5s1bzyI5a
+Kzz3bAnTmQsV0fhSEKmVGalsCMaerYAoIe7f/2Y3d8IVrPtE2XSjTul37vnx47iT
-0jRbdGmQ5N3eMWsw3TNjENm7AMU0BWJhAoIBAQCdW0LoiFahv/zrqM/gBE88C1fS
+CQKbx1ldo5NrVFAWMGkwwTltvyfVWXR9AoIBAQC6lS+ptioI/jUX7L+OQQJvrspW
-w4/BrSl/bhLGZQqSbcr9SxM/2Y5xyE4RS52glSDfx4zlseI93SqQDKLfGP+bjI9d
+jjxzW+JsCVdm6FvVGgWHMkcdUg5JIUvBj+ifBkIgqReiHr9AtNX5NooxR449B7zK
-HG07T3SELvs816SFRuGC+ktw3mFjFaGn4KlLtOsGcPRMZofsm/XdUNpWj5Ic4d5/
+HNsaNqCs2V0gT9vgGaPvakC4ThKQf8vSUF04ECMdFmxJTvlCM3mGbxn/M4bE4OPc
-4YWwBQn9VaODDvrhCcv+biA0vRBPlH67gubCy8RMb7J2GspMU9ekIjQxHJkVLY/a
+ypMb1qh4AhJyt4PMP1Ds8TAjmNRQ9LhoITXcuzlgZIbvOyA6Nz7dz5w3iUoOMyTl
-k9gBVdAtzeQY9VHLsc5/zTXReXUCyvrUw+h2hVtGx3CgncKH4WWELBWHXZqQJ6kJ
+SvZ1jMvHGiKHJJD0oYsf1q2YcNvBGT7lvOxJF1LR0AKgfTuqckJOVX4SdiWjgnEI
-sZhZ+KH9b6XGnSY29wPX1GKCTIXXIfN5xzFo65yw2b8WE0u0idvEsv1oKqtC
+oEPbjc5sl4Vq+DDNstIQC4/vGbAkeFDozaU+rySXTS2QESyNj9EtbW/uOkLr
 -----END rsa private key-----

cryptor/rsa_public_example.pem

@@ -1,14 +1,14 @@
 -----BEGIN rsa public key-----
-MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAtKEukXkdl8ggX5I5Us0M
+MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAtXr+2FbR6Prdf9U0gfq2
-BcsrFzbTgwOn8u72IhJzruvsHcjlGGF5L1eXh3C0zbcoWq+Bxf8NnXvSXASZlZHT
+OJbTD82m84bbdeyfsakabYp8Haw6mZW6ebRNPJvQ87H6DbA55hK1E7y6m+wjvbUo
-iSVLFerxFw2LwTNcyfOz/Y/wIbtrYu4ZdttLKdJS607UvnZ57O7SQni5rxYAP5j+
+pnkGh75Cp04CoQvaU8Rs7MrQcJ2Zz1VRRgugmqwJMWE/FC5eGXvvpDjF2h2lqThK
-veKHEJgAO7Sn0lEEWwkeudsfVrQmQx6JHYtCtx78p2GHXPj9wXWHxWHKMkczKtmB
+ZTKcvhqfZ3dNX+6v4EQ4BbjSGKdzpyexzR1WSV9IzZYRHMk8jCoEHOx9ItEzoToB
-FDLlYocPhQfWzx87sYKjGmTMGzVddsrllAqVozlxXTQndOdozx8BWHSBiYWguOvW
+f9yAq0DhufylqSRbjKLhR7A3IiRSLVNfu0Sz5cfNlS7eUA060QS8AV9BgGNTkl75
-iYjvryrIf0B7wn4wt3o2Yre3w4BkwrTUE73JWG2q1NLuPoT27m7WcdVFGGcKAygA
+aj8BCOmoHIW85SsSZvdQWYwmlM76Jn+tfNNnY7Uuqtz2gI1odcy1nXembXWJryxu
-dMMSwS530v8tnAw876/w1SfUmtkIcqknysMjsvxHx1fbEfkl3b0yBnzcUrT1qxzm
+YCkSAwpU8UNIQpZeKwBnBxaf0pj3W1m3UzEqhGkkCrKq8LkNSGZSkhT+bI65fNx2
-NEqJSQXBtFYFyGgyeL8J1ul/T5hPSNz0we5TO/xRkX5Y1HNJ+a2r8EnE1PU8zgQG
+LZ7lS165szkeyqS8aikxcBpdx7Z/bqbFFuI42KX+IpXAJCAtvsQ0XXinr83MLcY/
-BxYSIub4ajSUccyn5yHQ/k2FlsolZiu/UzfnzMgdg55svgf5x1ntKYBoVHuYe84A
+I2Ic/5Sgz7txfZsKKwKt48ETS9BjxGPWo1Dd5YjM8ZJWJv2Rf0mwVjUMClFSNBm8
-b3WRAeVlUi0OphvFlBzfIQvrG2sRbiPZRZZ0E8kBH94zPmrFmyX+7TwlSqVHtNFc
+x+aWGVIKjpocN/plpEZmFrWdPcWM4ZH3qGCEnVVkqPvqClahNSQXsM4W7msYts1I
-+Ynz+hrHcd4z6N7fIb+D1gSYuukkcRqr4ANO0ugZk0YYKaWDf86H7OZOXna8ObIA
+Uq31tjBSV5bL6l2K8jFJa4PRYdzh1vHhDOAYTpgDkQbNaoDlDS2o/0TkAGUfXWJt
-i+3gx+Wcp1lm7Ffk9sn+dGkCAwEAAQ==
+R3D35wRJzoa7bCMt5BuFE3sCAwEAAQ==
 -----END rsa public key-----

datastructure/link/singlylink_test.go

@@ -15,7 +15,6 @@ func TestSinglyLink_InsertAtFirst(t *testing.T) {
 	link.InsertAtHead(1)
 	link.InsertAtHead(2)
 	link.InsertAtHead(3)
-	link.Print()
 
 	expected := []int{3, 2, 1}
 	values := link.Values()
@@ -32,7 +31,6 @@ func TestSinglyLink_InsertAtTail(t *testing.T) {
 	link.InsertAtTail(1)
 	link.InsertAtTail(2)
 	link.InsertAtTail(3)
-	link.Print()
 
 	expected := []int{1, 2, 3}
 	values := link.Values()
@@ -77,7 +75,6 @@ func TestSinglyLink_DeleteAtHead(t *testing.T) {
 	link.InsertAtTail(4)
 
 	link.DeleteAtHead()
-	link.Print()
 
 	expected := []int{2, 3, 4}
 	values := link.Values()

eventbus/eventbus_example_test.go

@@ -2,6 +2,7 @@ package eventbus
 
 import (
 	"fmt"
+	"sort"
 	"sync"
 	"time"
 )
@@ -224,6 +225,7 @@ func ExampleEventBus_GetEvents() {
 	eb.Subscribe("event2", func(eventData int) {}, false, 0, nil)
 
 	events := eb.GetEvents()
+	sort.Strings(events)
 
 	for _, event := range events {
 		fmt.Println(event)

eventbus/eventbus_test.go

@@ -1,6 +1,7 @@
 package eventbus
 
 import (
+	"sort"
 	"sync"
 	"testing"
 	"time"
@@ -213,7 +214,8 @@ func TestEventBus_GetEvents(t *testing.T) {
 	eb.Subscribe("event2", func(eventData int) {}, false, 0, nil)
 
 	events := eb.GetEvents()
+	sort.Strings(events)
 
 	assert.Equal(2, len(events))
-	assert.EqualValues([]string{"event1", "event2"}, events)
+	assert.Equal([]string{"event1", "event2"}, events)
 }

netutil/http_test.go

@@ -3,7 +3,6 @@ package netutil
 import (
 	"bytes"
 	"encoding/json"
-	"io"
 	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
@@ -27,8 +26,8 @@ func TestHttpGet(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestHttpPost(t *testing.T) {
@@ -49,8 +48,8 @@ func TestHttpPost(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestHttpPostFormData(t *testing.T) {
@@ -69,8 +68,8 @@ func TestHttpPostFormData(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestHttpPut(t *testing.T) {
@@ -92,8 +91,8 @@ func TestHttpPut(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestHttpPatch(t *testing.T) {
@@ -115,8 +114,8 @@ func TestHttpPatch(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestHttpDelete(t *testing.T) {
@@ -127,8 +126,8 @@ func TestHttpDelete(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestConvertMapToQueryString(t *testing.T) {
@@ -229,8 +228,8 @@ func TestHttpClent_Post(t *testing.T) {
 		return
 	}
 
-	body, _ := io.ReadAll(resp.Body)
+	defer resp.Body.Close()
-	t.Log("response: ", resp.StatusCode, string(body))
+	t.Log("response status:", resp.StatusCode)
 }
 
 func TestStructToUrlValues(t *testing.T) {

strutil/string.go

@@ -37,16 +37,17 @@ func CamelCase(s string) string {
 // Capitalize converts the first character of a string to upper case and the remaining to lower case.
 // Play: https://go.dev/play/p/2OAjgbmAqHZ
 func Capitalize(s string) string {
-	result := make([]rune, len(s))
+	if s == "" {
-	for i, v := range s {
+		return s
-		if i == 0 {
-			result[i] = unicode.ToUpper(v)
-		} else {
-			result[i] = unicode.ToLower(v)
-		}
 	}
 
-	return string(result)
+	runes := []rune(s)
+	runes[0] = unicode.ToUpper(runes[0])
+	for i := 1; i < len(runes); i++ {
+		runes[i] = unicode.ToLower(runes[i])
+	}
+
+	return string(runes)
 }
 
 // UpperFirst converts the first character of string to upper case.
@@ -127,51 +128,59 @@ func UpperSnakeCase(s string) string {
 // Before returns the substring of the source string up to the first occurrence of the specified string.
 // Play: https://go.dev/play/p/JAWTZDS4F5w
 func Before(s, char string) string {
-	i := strings.Index(s, char)
+	if char == "" {
-
-	if s == "" || char == "" || i == -1 {
 		return s
 	}
 
-	return s[0:i]
+	if i := strings.Index(s, char); i >= 0 {
+		return s[:i]
+	}
+
+	return s
 }
 
 // BeforeLast returns the substring of the source string up to the last occurrence of the specified string.
 // Play: https://go.dev/play/p/pJfXXAoG_Te
 func BeforeLast(s, char string) string {
-	i := strings.LastIndex(s, char)
+	if char == "" {
-
-	if s == "" || char == "" || i == -1 {
 		return s
 	}
 
-	return s[0:i]
+	if i := strings.LastIndex(s, char); i >= 0 {
+		return s[:i]
+	}
+
+	return s
 }
 
 // After returns the substring after the first occurrence of a specified string in the source string.
 // Play: https://go.dev/play/p/RbCOQqCDA7m
 func After(s, char string) string {
-	i := strings.Index(s, char)
+	if char == "" {
-
-	if s == "" || char == "" || i == -1 {
 		return s
 	}
 
+	if i := strings.Index(s, char); i >= 0 {
 		return s[i+len(char):]
 	}
 
+	return s
+}
+
 // AfterLast returns the substring after the last occurrence of a specified string in the source string.
 // Play: https://go.dev/play/p/1TegARrb8Yn
 func AfterLast(s, char string) string {
-	i := strings.LastIndex(s, char)
+	if char == "" {
-
-	if s == "" || char == "" || i == -1 {
 		return s
 	}
 
+	if i := strings.LastIndex(s, char); i >= 0 {
 		return s[i+len(char):]
 	}
 
+	return s
+}
+
 // IsString check if the value data type is string or not.
 // Play: https://go.dev/play/p/IOgq7oF9ERm
 func IsString(v any) bool {
@@ -213,22 +222,17 @@ func Wrap(str string, wrapWith string) string {
 // Unwrap a given string from anther string. will change source string.
 // Play: https://go.dev/play/p/Ec2q4BzCpG-
 func Unwrap(str string, wrapToken string) string {
-	if str == "" || wrapToken == "" {
+	if wrapToken == "" || !strings.HasPrefix(str, wrapToken) || !strings.HasSuffix(str, wrapToken) {
 		return str
 	}
 
-	firstIndex := strings.Index(str, wrapToken)
+	if len(str) < 2*len(wrapToken) {
-	lastIndex := strings.LastIndex(str, wrapToken)
-
-	if firstIndex == 0 && lastIndex > 0 && lastIndex <= len(str)-1 {
-		if len(wrapToken) <= lastIndex {
-			str = str[len(wrapToken):lastIndex]
-		}
-	}
-
 		return str
 	}
 
+	return str[len(wrapToken) : len(str)-len(wrapToken)]
+}
+
 // SplitEx split a given string which can control the result slice contains empty string or not.
 // Play: https://go.dev/play/p/Us-ySSbWh-3
 func SplitEx(s, sep string, removeEmptyString bool) []string {
@@ -286,22 +290,21 @@ func Substring(s string, offset int, length uint) string {
 	size := len(rs)
 
 	if offset < 0 {
-		offset = size + offset
+		offset += size
+	}
 	if offset < 0 {
 		offset = 0
 	}
-	}
 	if offset > size {
 		return ""
 	}
 
-	if length > uint(size)-uint(offset) {
+	end := offset + int(length)
-		length = uint(size - offset)
+	if end > size {
+		end = size
 	}
 
-	str := string(rs[offset : offset+int(length)])
+	return strings.ReplaceAll(string(rs[offset:end]), "\x00", "")
-
-	return strings.Replace(str, "\x00", "", -1)
 }
 
 // SplitWords splits a string into words, word only contains alphabetic characters.

strutil/string_internal.go

@@ -1,6 +1,7 @@
 package strutil
 
 import (
+	"strings"
 	"unicode"
 )
 
@@ -111,31 +112,27 @@ func padAtPosition(str string, length int, padStr string, position int) string {
 		padStr = " "
 	}
 
-	length = length - len(str)
+	totalPad := length - len(str)
-	startPadLen := 0
+	startPad := 0
+
 	if position == 0 {
-		startPadLen = length / 2
+		startPad = totalPad / 2
 	} else if position == 1 {
-		startPadLen = length
+		startPad = totalPad
+	} else if position == 2 {
+		startPad = 0
 	}
-	endPadLen := length - startPadLen
+	endPad := totalPad - startPad
 
-	charLen := len(padStr)
+	repeatPad := func(n int) string {
-	leftPad := ""
+		repeated := strings.Repeat(padStr, (n+len(padStr)-1)/len(padStr))
-	cur := 0
+		return repeated[:n]
-	for cur < startPadLen {
-		leftPad += string(padStr[cur%charLen])
-		cur++
 	}
 
-	cur = 0
+	left := repeatPad(startPad)
-	rightPad := ""
+	right := repeatPad(endPad)
-	for cur < endPadLen {
-		rightPad += string(padStr[cur%charLen])
-		cur++
-	}
 
-	return leftPad + str + rightPad
+	return left + str + right
 }
 
 // isLetter checks r is a letter but not CJK character.