From 0828ec1ea8f1733d61db0893fe8c03abbcebc2e5 Mon Sep 17 00:00:00 2001 From: Tim Cooper Date: Wed, 27 Sep 2017 20:31:55 -0300 Subject: [PATCH] flag: align multi-line usage strings Previously, a multi-line flag usage string would not be indented with the rest of the usage strings. This made long usage strings difficult to read. For example, the usage for flag.String("A", "", "1\n2\n3") would be printed as: -A 1 2 3 But will now be printed as: -A 1 2 3 Also fixes a slight error in the FlagSet.PrintDefaults documentation. Fixes #20799 Change-Id: I4379c6b7590fdb93a2809a01046a0f6ae32c3e5d Reviewed-on: https://go-review.googlesource.com/66711 Run-TryBot: Russ Cox TryBot-Result: Gobot Gobot Reviewed-by: Russ Cox --- src/flag/flag.go | 10 ++++++---- src/flag/flag_test.go | 8 ++++++++ 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/src/flag/flag.go b/src/flag/flag.go index a1a8dc7fad..5544a25282 100644 --- a/src/flag/flag.go +++ b/src/flag/flag.go @@ -71,6 +71,7 @@ import ( "reflect" "sort" "strconv" + "strings" "time" ) @@ -448,9 +449,9 @@ func UnquoteUsage(flag *Flag) (name string, usage string) { return } -// PrintDefaults prints to standard error the default values of all -// defined command-line flags in the set. See the documentation for -// the global function PrintDefaults for more information. +// PrintDefaults prints, to standard error unless configured otherwise, the +// default values of all defined command-line flags in the set. See the +// documentation for the global function PrintDefaults for more information. func (f *FlagSet) PrintDefaults() { f.VisitAll(func(flag *Flag) { s := fmt.Sprintf(" -%s", flag.Name) // Two spaces before -; see next two comments. @@ -467,7 +468,8 @@ func (f *FlagSet) PrintDefaults() { // for both 4- and 8-space tab stops. s += "\n \t" } - s += usage + s += strings.Replace(usage, "\n", "\n \t", -1) + if !isZeroValue(flag, flag.DefValue) { if _, ok := flag.Value.(*stringValue); ok { // put quotes on the value diff --git a/src/flag/flag_test.go b/src/flag/flag_test.go index 20d09c4c41..4c6db96ba0 100644 --- a/src/flag/flag_test.go +++ b/src/flag/flag_test.go @@ -389,8 +389,14 @@ const defaultOutput = ` -A for bootstrapping, allow 'any' type a non-zero number (default 2.7) -G float a float that defaults to zero + -M string + a multiline + help + string -N int a non-zero int (default 27) + -O a flag + multiline help string (default true) -Z int an int that defaults to zero -maxT timeout @@ -407,7 +413,9 @@ func TestPrintDefaults(t *testing.T) { fs.String("D", "", "set relative `path` for local imports") fs.Float64("F", 2.7, "a non-zero `number`") fs.Float64("G", 0, "a float that defaults to zero") + fs.String("M", "", "a multiline\nhelp\nstring") fs.Int("N", 27, "a non-zero int") + fs.Bool("O", true, "a flag\nmultiline help string") fs.Int("Z", 0, "an int that defaults to zero") fs.Duration("maxT", 0, "set `timeout` for dial") fs.PrintDefaults() -- 2.48.1