time: add examples for Since, Until, Abs and fix some comments

Change-Id: I33b61629dfabffa15065a14fccdb418bab11350d
Reviewed-on: https://go-review.googlesource.com/c/go/+/623915
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: David Chase <drchase@google.com>

diff --git a/src/time/example_test.go b/src/time/example_test.go
index 53c20a051672a84eab4818e801c499366e3ce695..2c9601c6115a9c37226deb042a15a927ba8441d3 100644 (file)
--- a/src/time/example_test.go
+++ b/src/time/example_test.go
@@ -6,6 +6,7 @@ package time_test
 
 import (
        "fmt"
+       "math"
        "time"
 )
 
@@ -108,6 +109,39 @@ func ExampleParseDuration() {
        // There are 1.00e-06 seconds in 1µs.
 }
 
+func ExampleSince() {
+       start := time.Now()
+       expensiveCall()
+       elapsed := time.Since(start)
+       fmt.Printf("The call took %v to run.\n", elapsed)
+}
+
+func ExampleUntil() {
+       futureTime := time.Now().Add(5 * time.Second)
+       durationUntil := time.Until(futureTime)
+       fmt.Printf("Duration until future time: %.0f seconds", math.Ceil(durationUntil.Seconds()))
+       // Output: Duration until future time: 5 seconds
+}
+
+func ExampleDuration_Abs() {
+       positiveDuration := 5 * time.Second
+       negativeDuration := -3 * time.Second
+       minInt64CaseDuration := time.Duration(math.MinInt64)
+
+       absPositive := positiveDuration.Abs()
+       absNegative := negativeDuration.Abs()
+       absSpecial := minInt64CaseDuration.Abs() == time.Duration(math.MaxInt64)
+
+       fmt.Printf("Absolute value of positive duration: %v\n", absPositive)
+       fmt.Printf("Absolute value of negative duration: %v\n", absNegative)
+       fmt.Printf("Absolute value of MinInt64 equal to MaxInt64: %t\n", absSpecial)
+
+       // Output:
+       // Absolute value of positive duration: 5s
+       // Absolute value of negative duration: 3s
+       // Absolute value of MinInt64 equal to MaxInt64: true
+}
+
 func ExampleDuration_Hours() {
        h, _ := time.ParseDuration("4h30m")
        fmt.Printf("I've got %.1f hours of work left.", h.Hours())
@@ -295,8 +329,8 @@ func ExampleTime_Format() {
        // default format: 2015-02-25 11:06:39 -0800 PST
        // Unix format: Wed Feb 25 11:06:39 PST 2015
        // Same, in UTC: Wed Feb 25 19:06:39 UTC 2015
-       //in Shanghai with seconds: 2015-02-26T03:06:39 +080000
-       //in Shanghai with colon seconds: 2015-02-26T03:06:39 +08:00:00
+       // in Shanghai with seconds: 2015-02-26T03:06:39 +080000
+       // in Shanghai with colon seconds: 2015-02-26T03:06:39 +08:00:00
        //
        // Formats:
        //

diff --git a/src/time/format.go b/src/time/format.go
index b9cd702c0db3e7c5d9dd04ae4d3c85e2f8bc36da..da1bac5ac30d5819c2726312e5b4440e53345b14 100644 (file)
--- a/src/time/format.go
+++ b/src/time/format.go
@@ -250,7 +250,7 @@ func nextStdChunk(layout string) (prefix string, std int, suffix string) {
 
                case '_': // _2, _2006, __2
                        if len(layout) >= i+2 && layout[i+1] == '2' {
-                               //_2006 is really a literal _, followed by stdLongYear
+                               // _2006 is really a literal _, followed by stdLongYear
                                if len(layout) >= i+5 && layout[i+1:i+5] == "2006" {
                                        return layout[0 : i+1], stdLongYear, layout[i+5:]
                                }

diff --git a/src/time/tick_test.go b/src/time/tick_test.go
index fce9002cfcbb63a26596e6f52fc570d271cabcf3..416bef59ee91ee52c08a4389e54473c84082db04 100644 (file)
--- a/src/time/tick_test.go
+++ b/src/time/tick_test.go
@@ -462,7 +462,7 @@ func testTimerChan(t *testing.T, tim timer, C <-chan Time, synctimerchan bool) {
                tim.Reset(1)
                Sleep(sched)
                if l, c := len(C), cap(C); l != 0 || c != 0 {
-                       //t.Fatalf("len(C), cap(C) = %d, %d, want 0, 0", l, c)
+                       // t.Fatalf("len(C), cap(C) = %d, %d, want 0, 0", l, c)
                }
                assertTick()
        } else {

diff --git a/src/time/time_test.go b/src/time/time_test.go
index 2d719acde279d5da6837869ba908cb0447a7a064..ff253be46ba428ef8b37b6729238006b34f3670d 100644 (file)
--- a/src/time/time_test.go
+++ b/src/time/time_test.go
@@ -1400,7 +1400,7 @@ var defaultLocTests = []struct {
        {"Add", func(t1, t2 Time) bool { return t1.Add(Hour).Equal(t2.Add(Hour)) }},
        {"Sub", func(t1, t2 Time) bool { return t1.Sub(t2) == t2.Sub(t1) }},
 
-       //Original caus for this test case bug 15852
+       // Original cause for this test case bug 15852
        {"AddDate", func(t1, t2 Time) bool { return t1.AddDate(1991, 9, 3) == t2.AddDate(1991, 9, 3) }},
 
        {"UTC", func(t1, t2 Time) bool { return t1.UTC() == t2.UTC() }},