tpl: Add strings.Repeat

This commit is contained in:
David E. Wheeler 2018-06-03 02:55:37 -04:00 committed by Bjørn Erik Pedersen
parent 07b96d16e8
commit 13435a6f60
5 changed files with 109 additions and 0 deletions

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@ -0,0 +1,31 @@
---
title: strings.Repeat
# linktitle:
description: Returns a string consisting of count copies of the string s.
godocref:
date: 2018-05-31
publishdate: 2018-05-31
lastmod: 2018-05-31
categories: [functions]
menu:
docs:
parent: "functions"
keywords: [strings]
signature: ["strings.Repeat INPUT COUNT"]
workson: []
hugoversion:
relatedfuncs: []
deprecated: false
---
`strings.Repeat` provides the Go [`strings.Repeat`](https://golang.org/pkg/strings/#Repeat) function for Hugo templates. It takes a string and a count, and returns a string with consisting of count copies of the string argument.
```
{{ strings.Repeat "yo" 3 }} → "yoyoyo"
```
`strings.Repeat` *requires* the second argument, which tells the function how many times to repeat the first argument; there is no default. However, it can be used as a pipeline:
```
{{ "yo" | strings.Repeat 3 }} → "yoyoyo"
```

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@ -3410,6 +3410,20 @@
] ]
] ]
}, },
"Repeat": {
"Description": "Repeat returns a new string consisting of count copies of the string s.",
"Args": [
"s",
"n"
],
"Aliases": null,
"Examples": [
[
"{{ \"yo\" | strings.Repeat 4 }}",
"yoyoyoyo"
]
]
},
"Truncate": { "Truncate": {
"Description": "Truncate truncates a given string to the specified length.", "Description": "Truncate truncates a given string to the specified length.",
"Args": [ "Args": [

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@ -158,6 +158,13 @@ func init() {
}, },
) )
ns.AddMethodMapping(ctx.Repeat,
nil,
[][2]string{
{`{{ "yo" | strings.Repeat 4 }}`, `yoyoyoyo`},
},
)
ns.AddMethodMapping(ctx.ToUpper, ns.AddMethodMapping(ctx.ToUpper,
[]string{"upper"}, []string{"upper"},
[][2]string{ [][2]string{

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@ -17,6 +17,7 @@ import (
"errors" "errors"
"fmt" "fmt"
"html/template" "html/template"
"math"
_strings "strings" _strings "strings"
"unicode/utf8" "unicode/utf8"
@ -417,3 +418,23 @@ func (ns *Namespace) TrimSuffix(suffix, s interface{}) (string, error) {
return _strings.TrimSuffix(ss, sx), nil return _strings.TrimSuffix(ss, sx), nil
} }
// Repeat returns a new string consisting of count copies of the string s.
// The count is limited to an in16 value (up to 32767).
func (ns *Namespace) Repeat(n, s interface{}) (string, error) {
ss, err := cast.ToStringE(s)
if err != nil {
return "", err
}
sn, err := cast.ToIntE(n)
if err != nil {
return "", err
}
if sn > math.MaxInt16 {
return "", fmt.Errorf("Cannot repeat string more than %d times", math.MaxInt16)
}
return _strings.Repeat(ss, sn), nil
}

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@ -16,6 +16,7 @@ package strings
import ( import (
"fmt" "fmt"
"html/template" "html/template"
"math"
"testing" "testing"
"github.com/gohugoio/hugo/deps" "github.com/gohugoio/hugo/deps"
@ -709,3 +710,38 @@ func TestTrimSuffix(t *testing.T) {
assert.Equal(t, test.expect, result, errMsg) assert.Equal(t, test.expect, result, errMsg)
} }
} }
func TestRepeat(t *testing.T) {
t.Parallel()
for i, test := range []struct {
s interface{}
n interface{}
expect interface{}
}{
{"yo", "2", "yoyo"},
{"~", "16", "~~~~~~~~~~~~~~~~"},
{"<tag>", "0", ""},
{"yay", "1", "yay"},
{1221, "1", "1221"},
{1221, 2, "12211221"},
{template.HTML("<tag>"), "2", "<tag><tag>"},
{[]byte("<tag>"), 2, "<tag><tag>"},
// errors
{"", tstNoStringer{}, false},
{tstNoStringer{}, "", false},
{"hi", math.MaxInt16 + 1, false},
} {
errMsg := fmt.Sprintf("[%d] %v", i, test)
result, err := ns.Repeat(test.n, test.s)
if b, ok := test.expect.(bool); ok && !b {
require.Error(t, err, errMsg)
continue
}
require.NoError(t, err, errMsg)
assert.Equal(t, test.expect, result, errMsg)
}
}