doc: add doc for DayOfYear

datetime/datetime.go

@@ -238,9 +238,12 @@ func BetweenSeconds(t1 time.Time, t2 time.Time) int64 {
 	return index
 }
 
-func DayOfYear(t1 time.Time) int {
+// DayOfYear returns which day of the year the parameter date `t` is.
-	y, m, d := t1.Date()
+// Play: todo
-	firstDay := time.Date(y, 1, 1, 0, 0, 0, 0, t1.Location())
+func DayOfYear(t time.Time) int {
-	nowDate := time.Date(y, m, d, 0, 0, 0, 0, t1.Location())
+	y, m, d := t.Date()
+	firstDay := time.Date(y, 1, 1, 0, 0, 0, 0, t.Location())
+	nowDate := time.Date(y, m, d, 0, 0, 0, 0, t.Location())
+
 	return int(nowDate.Sub(firstDay).Hours() / 24)
 }

datetime/datetime_example_test.go

@@ -369,3 +369,23 @@ func ExampleBetweenSeconds() {
 	// 86400
 	// -86400
 }
+
+func ExampleDayOfYear() {
+	date1 := time.Date(2023, 02, 01, 1, 1, 1, 0, time.Local)
+	result1 := DayOfYear(date1)
+
+	date2 := time.Date(2023, 01, 02, 1, 1, 1, 0, time.Local)
+	result2 := DayOfYear(date2)
+
+	date3 := time.Date(2023, 01, 01, 1, 1, 1, 0, time.Local)
+	result3 := DayOfYear(date3)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+
+	// Output:
+	// 31
+	// 1
+	// 0
+}

datetime/datetime_test.go

@@ -274,15 +274,15 @@ func TestIsLeapYear(t *testing.T) {
 
 func TestDayOfYear(t *testing.T) {
 	assert := internal.NewAssert(t, "TestDayOfYear")
-	date := time.Date(2023, 02, 01, 1, 1, 1, 0, time.Local)
+	date1 := time.Date(2023, 02, 01, 1, 1, 1, 0, time.Local)
-	result := DayOfYear(date)
-	assert.Equal(31, result)
-
-	date1 := time.Date(2023, 01, 02, 1, 1, 1, 0, time.Local)
 	result1 := DayOfYear(date1)
-	assert.Equal(1, result1)
+	assert.Equal(31, result1)
+
+	date2 := time.Date(2023, 01, 02, 1, 1, 1, 0, time.Local)
+	result2 := DayOfYear(date2)
+	assert.Equal(1, result2)
 
 	date3 := time.Date(2023, 01, 01, 1, 1, 1, 0, time.Local)
-	result2 := DayOfYear(date3)
+	result3 := DayOfYear(date3)
-	assert.Equal(0, result2)
+	assert.Equal(0, result3)
 }

docs/datetime.md

@@ -56,6 +56,7 @@ import (
 -   [ToIso8601](#ToIso8601)
 -   [IsLeapYear](#IsLeapYear)
 -   [BetweenSeconds](#BetweenSeconds)
+-   [DayOfYear](#DayOfYear)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -1175,3 +1176,45 @@ func main() {
     // -86400
 }
 ```
+
+
+### <span id="DayOfYear">DayOfYear</span>
+
+<p>Returns which day of the year the parameter date `t` is.</p>
+
+<b>Signature:</b>
+
+```go
+func DayOfYear(t time.Time) int
+```
+
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/datetime"
+)
+
+func main() {
+    date1 := time.Date(2023, 02, 01, 1, 1, 1, 0, time.Local)
+    result1 := datetime.DayOfYear(date1)
+
+    date2 := time.Date(2023, 01, 02, 1, 1, 1, 0, time.Local)
+    result2 := datetime.DayOfYear(date2)
+
+    date3 := time.Date(2023, 01, 01, 1, 1, 1, 0, time.Local)
+    result3 := datetime.DayOfYear(date3)
+
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)
+
+    // Output:
+    // 31
+    // 1
+    // 0
+}
+```

docs/datetime_zh-CN.md

@@ -55,6 +55,7 @@ import (
 -   [ToIso8601](#ToIso8601)
 -   [IsLeapYear](#IsLeapYear)
 -   [BetweenSeconds](#BetweenSeconds)
+-   [DayOfYear](#DayOfYear)
 
 
 <div STYLE="page-break-after: always;"></div>
@@ -1174,3 +1175,44 @@ func main() {
     // -86400
 }
 ```
+
+### <span id="DayOfYear">DayOfYear</span>
+
+<p>返回参数日期是一年中的第几天。</p>
+
+<b>函数签名:</b>
+
+```go
+func DayOfYear(t time.Time) int
+```
+
+<b>示例:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/datetime"
+)
+
+func main() {
+    date1 := time.Date(2023, 02, 01, 1, 1, 1, 0, time.Local)
+    result1 := datetime.DayOfYear(date1)
+
+    date2 := time.Date(2023, 01, 02, 1, 1, 1, 0, time.Local)
+    result2 := datetime.DayOfYear(date2)
+
+    date3 := time.Date(2023, 01, 01, 1, 1, 1, 0, time.Local)
+    result3 := datetime.DayOfYear(date3)
+
+    fmt.Println(result1)
+    fmt.Println(result2)
+    fmt.Println(result3)
+
+    // Output:
+    // 31
+    // 1
+    // 0
+}
+```