Support Custom Assert (#755)

* custom Assert

* disable Test Parallel

* golangcli-lint warning fix

* Document custom handler for lo.Assert

Added a section on creating a custom handler for lo.Assert.

---------

Co-authored-by: Samuel Berthe <dev@samuel-berthe.fr>

Author: RelicOfTesla

docs/data/core-assert.md

@@ -45,4 +45,14 @@ lo.Assert(age >= 15, "user age must be >= 15")
 // continues normally
 ```
 
+## Custom handler
 
+Replace `lo.Assert` and `lo.Assertf` with your own statement:
+
+```go
+lo.Assertf = func(condition bool, format string, args ...any) {
+		if !condition {
+			  panic(fmt.Errorf("%s: %s", "customErr", fmt.Sprintf(format, args...)))
+		}
+}
+```

errors.go

@@ -356,7 +356,7 @@ func ErrorsAs[T error](err error) (T, bool) {
 
 // Assert does nothing when the condition is true, otherwise it panics with an optional message.
 // Play: https://go.dev/play/p/Xv8LLKBMNwI
-func Assert(condition bool, message ...string) {
+var Assert = func(condition bool, message ...string) {
 	if condition {
 		return
 	}
@@ -370,7 +370,7 @@ func Assert(condition bool, message ...string) {
 
 // Assertf does nothing when the condition is true, otherwise it panics with a formatted message.
 // Play: https://go.dev/play/p/TVPEmVcyrdY
-func Assertf(condition bool, format string, args ...any) {
+var Assertf = func(condition bool, format string, args ...any) {
 	if condition {
 		return
 	}

errors_test.go

@@ -2,6 +2,7 @@ package lo
 
 import (
 	"errors"
+	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -600,8 +601,8 @@ func TestErrorsAs(t *testing.T) {
 	is.Nil(err)
 }
 
-func TestAssert(t *testing.T) {
-	t.Parallel()
+func TestAssert(t *testing.T) { //nolint:paralleltest
+	// t.Parallel()
 	is := assert.New(t)
 
 	is.NotPanics(func() {
@@ -632,8 +633,8 @@ func TestAssert(t *testing.T) {
 	}
 }
 
-func TestAssertf(t *testing.T) {
-	t.Parallel()
+func TestAssertf(t *testing.T) { //nolint:paralleltest
+	// t.Parallel()
 	is := assert.New(t)
 
 	is.NotPanics(func() {
@@ -660,3 +661,25 @@ func TestAssertf(t *testing.T) {
 		})
 	}
 }
+
+func TestAssertfWithCustom(t *testing.T) { //nolint:paralleltest
+	oldAssertf := Assertf
+	Assertf = func(condition bool, format string, args ...any) {
+		if !condition {
+			panic(fmt.Errorf("%s: %s", "customErr", fmt.Sprintf(format, args...)))
+		}
+	}
+	defer func() {
+		Assertf = oldAssertf
+	}()
+
+	e, ok := TryWithErrorValue(func() error {
+		Assertf(false, "user defined message")
+		return nil
+	})
+	assert.False(t, ok)
+	assert.NotNil(t, e)
+	err, ok := e.(error)
+	assert.True(t, ok)
+	assert.Equal(t, "customErr: user defined message", err.Error())
+}