feat: add DaysBetween in datetime package

datetime/datetime.go

@@ -411,3 +411,12 @@ func getCallerName() string {
 
 	return fullName
 }
+
+// DaysBetween returns the number of days between two times.
+// Play: todo
+func DaysBetween(start, end time.Time) int {
+	duration := end.Sub(start)
+	days := int(duration.Hours() / 24)
+
+	return days
+}

datetime/datetime_example_test.go

@@ -409,16 +409,14 @@ func ExampleIsWeekend() {
 	// false
 }
 
-// func ExampleTrackFuncTime() {
-// 	defer TrackFuncTime(time.Now())()
+func ExampleDaysBetween() {
+	start := time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC)
+	end := time.Date(2024, time.September, 10, 0, 0, 0, 0, time.UTC)
 
-// 	var n int
-// 	for i := 0; i < 5000000; i++ {
-// 		n++
-// 	}
+	result := DaysBetween(start, end)
 
-// 	fmt.Println(1)
+	fmt.Println(result)
 
-// 	// Output:
-// 	// 1
-// }
+	// Output:
+	// 9
+}

datetime/datetime_test.go

@@ -419,3 +419,46 @@ func TestTrackFuncTime(t *testing.T) {
 		n++
 	}
 }
+
+func TestDaysBetween(t *testing.T) {
+	t.Parallel()
+
+	assert := internal.NewAssert(t, "TestDaysBetween")
+
+	tests := []struct {
+		start    time.Time
+		end      time.Time
+		expected int
+	}{
+		{
+			start:    time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC),
+			end:      time.Date(2024, time.September, 10, 0, 0, 0, 0, time.UTC),
+			expected: 9,
+		},
+		{
+			start:    time.Date(2024, time.September, 10, 0, 0, 0, 0, time.UTC),
+			end:      time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC),
+			expected: -9,
+		},
+		{
+			start:    time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC),
+			end:      time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC),
+			expected: 0,
+		},
+		{
+			start:    time.Date(2024, time.January, 1, 0, 0, 0, 0, time.UTC),
+			end:      time.Date(2024, time.December, 31, 0, 0, 0, 0, time.UTC),
+			expected: 365,
+		},
+		{
+			start:    time.Date(2024, time.March, 1, 0, 0, 0, 0, time.UTC),
+			end:      time.Date(2024, time.March, 31, 0, 0, 0, 0, time.UTC),
+			expected: 30,
+		},
+	}
+
+	for _, tt := range tests {
+		result := DaysBetween(tt.start, tt.end)
+		assert.Equal(tt.expected, result)
+	}
+}

docs/api/packages/datetime.md

@@ -65,6 +65,7 @@ import (
 -   [TimestampMicro](#TimestampMicro)
 -   [TimestampNano](#TimestampNano)
 -   [TrackFuncTime](#TrackFuncTime)
+-   [DaysBetween](#DaysBetween)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -1497,4 +1498,37 @@ func main() {
 
     fmt.Println(1) // Function main execution time:     1.460287ms
 }
+```
+
+### <span id="DaysBetween">DaysBetween</span>
+
+<p>返回两个日期之间的天数差。</p>
+
+<b>函数签名:</b>
+
+```go
+func DaysBetween(start, end time.Time) int
+```
+
+<b>示例:<span style="float:right;display:inline-block;">[运行]()</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/datetime"
+)
+
+func main() {
+    start := time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC)
+    end := time.Date(2024, time.September, 10, 0, 0, 0, 0, time.UTC)
+
+    result := datetime.DaysBetween(start, end)
+
+    fmt.Println(result)
+
+    // Output:
+    // 9
+}
 ```

docs/en/api/packages/datetime.md

@@ -1498,3 +1498,36 @@ func main() {
     fmt.Println(1) // Function main execution time:     1.460287ms
 }
 ```
+
+### <span id="DaysBetween">DaysBetween</span>
+
+<p>Returns the number of days between two times.</p>
+
+<b>Signature:</b>
+
+```go
+func DaysBetween(start, end time.Time) int
+```
+
+<b>Example:<span style="float:right;display:inline-block;">[Run]()</span></b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/datetime"
+)
+
+func main() {
+    start := time.Date(2024, time.September, 1, 0, 0, 0, 0, time.UTC)
+    end := time.Date(2024, time.September, 10, 0, 0, 0, 0, time.UTC)
+
+    result := datetime.DaysBetween(start, end)
+
+    fmt.Println(result)
+
+    // Output:
+    // 9
+}
+```