Navigation Menu

Skip to content

Commit

Permalink
Make sort tpl func accept field/key chaining arg
Browse files Browse the repository at this point in the history 
'sort' template function used to accept only each element's struct field
name, method name and map key name as its second argument. This extends
it to accept a field/method/key chaining key string like
'Params.foo.bar' as the argument. It evaluates sub elements of each
array or map elements and sorts by them.

Typical use case would be sorting pages by user defined front matter
value. For example, sorting pages by 'Params.foo.bar' is possible by
writing the following template code

    {{ range sort .Data.Pages "Params.foo.bar" }}
        {{ .Content }}
    {{ end }}

It ignores all leading and trailing dots so "Params.foo.bar" can be
written in ".Params.foo.bar"

This also fixes the issue that 'sort' cannot evaluate a pointer value.

Fix gohugoio#1330
  • Loading branch information
@tatsushid @tychoish
tatsushid authored and tychoish committed Aug 13, 2017
1 parent 05d9d30 commit 160bbb9
Show file tree
Hide file tree
Showing 2 changed files with 181 additions and 40 deletions.
79 changes: 46 additions & 33 deletions tpl/template_funcs.go
View file
Expand Up @@ -882,43 +882,74 @@ func Sort(seq interface{}, args ...interface{}) (interface{}, error) {
return nil, errors.New("can't iterate over a nil value")
}

switch seqv.Kind() {
case reflect.Array, reflect.Slice, reflect.Map:
// ok
default:
return nil, errors.New("can't sort " + reflect.ValueOf(seq).Type().String())
}

// Create a list of pairs that will be used to do the sort
p := pairList{SortAsc: true, SliceType: reflect.SliceOf(seqv.Type().Elem())}
p.Pairs = make([]pair, seqv.Len())

var sortByField string
for i, l := range args {
dStr, err := cast.ToStringE(l)
switch {
case i == 0 && err != nil:
p.SortByField = ""
sortByField = ""
case i == 0 && err == nil:
p.SortByField = dStr
sortByField = dStr
case i == 1 && err == nil && dStr == "desc":
p.SortAsc = false
case i == 1:
p.SortAsc = true
}
}
path := strings.Split(strings.Trim(sortByField, "."), ".")

switch seqv.Kind() {
case reflect.Array, reflect.Slice:
for i := 0; i < seqv.Len(); i++ {
p.Pairs[i].Key = reflect.ValueOf(i)
p.Pairs[i].Value = seqv.Index(i)
}
if p.SortByField == "" {
p.SortByField = "value"
if sortByField == "" || sortByField == "value" {
p.Pairs[i].SortByValue = p.Pairs[i].Value
} else {
v := p.Pairs[i].Value
var err error
for _, elemName := range path {
v, err = evaluateSubElem(v, elemName)
if err != nil {
return nil, err
}
}
p.Pairs[i].SortByValue = v
}
}

case reflect.Map:
keys := seqv.MapKeys()
for i := 0; i < seqv.Len(); i++ {
p.Pairs[i].Key = keys[i]
p.Pairs[i].Value = seqv.MapIndex(keys[i])
if sortByField == "" {
p.Pairs[i].SortByValue = p.Pairs[i].Key
} else if sortByField == "value" {
p.Pairs[i].SortByValue = p.Pairs[i].Value
} else {
v := p.Pairs[i].Value
var err error
for _, elemName := range path {
v, err = evaluateSubElem(v, elemName)
if err != nil {
return nil, err
}
}
p.Pairs[i].SortByValue = v
}
}

default:
return nil, errors.New("can't sort " + reflect.ValueOf(seq).Type().String())
}
return p.sort(), nil
}
Expand All @@ -927,40 +958,22 @@ func Sort(seq interface{}, args ...interface{}) (interface{}, error) {
// https://groups.google.com/forum/#!topic/golang-nuts/FT7cjmcL7gw
// A data structure to hold a key/value pair.
type pair struct {
Key reflect.Value
Value reflect.Value
Key reflect.Value
Value reflect.Value
SortByValue reflect.Value
}

// A slice of pairs that implements sort.Interface to sort by Value.
type pairList struct {
Pairs []pair
SortByField string
SortAsc bool
SliceType reflect.Type
Pairs []pair
SortAsc bool
SliceType reflect.Type
}

func (p pairList) Swap(i, j int) { p.Pairs[i], p.Pairs[j] = p.Pairs[j], p.Pairs[i] }
func (p pairList) Len() int { return len(p.Pairs) }
func (p pairList) Less(i, j int) bool {
var truth bool
switch {
case p.SortByField == "value":
iVal := p.Pairs[i].Value
jVal := p.Pairs[j].Value
truth = Lt(iVal.Interface(), jVal.Interface())

case p.SortByField != "":
if p.Pairs[i].Value.FieldByName(p.SortByField).IsValid() {
iVal := p.Pairs[i].Value.FieldByName(p.SortByField)
jVal := p.Pairs[j].Value.FieldByName(p.SortByField)
truth = Lt(iVal.Interface(), jVal.Interface())
}
default:
iVal := p.Pairs[i].Key
jVal := p.Pairs[j].Key
truth = Lt(iVal.Interface(), jVal.Interface())
}
return truth
return Lt(p.Pairs[i].SortByValue.Interface(), p.Pairs[j].SortByValue.Interface())
}

// sorts a pairList and returns a slice of sorted values
Expand Down
142 changes: 135 additions & 7 deletions tpl/template_funcs_test.go
View file
Expand Up @@ -1081,6 +1081,10 @@ func TestSort(t *testing.T) {
MyFloat float64
MyString string
}
type mid struct {
Tst TstX
}

for i, this := range []struct {
sequence interface{}
sortByField interface{}
Expand All @@ -1091,6 +1095,8 @@ func TestSort(t *testing.T) {
{[]string{"class3", "class1", "class2"}, nil, "asc", []string{"class1", "class2", "class3"}},
{[]int{1, 2, 3, 4, 5}, nil, "asc", []int{1, 2, 3, 4, 5}},
{[]int{5, 4, 3, 1, 2}, nil, "asc", []int{1, 2, 3, 4, 5}},
// test sort key parameter is focibly set empty
{[]string{"class3", "class1", "class2"}, map[int]string{1: "a"}, "asc", []string{"class1", "class2", "class3"}},
// test map sorting by keys
{map[string]int{"1": 10, "2": 20, "3": 30, "4": 40, "5": 50}, nil, "asc", []int{10, 20, 30, 40, 50}},
{map[string]int{"3": 10, "2": 20, "1": 30, "4": 40, "5": 50}, nil, "asc", []int{30, 20, 10, 40, 50}},
Expand Down Expand Up @@ -1122,9 +1128,124 @@ func TestSort(t *testing.T) {
"asc",
[]ts{{50, 50.5, "fifty"}, {40, 40.5, "forty"}, {10, 10.5, "ten"}, {30, 30.5, "thirty"}, {20, 20.5, "twenty"}},
},
// Test sort desc
// test sort desc
{[]string{"class1", "class2", "class3"}, "value", "desc", []string{"class3", "class2", "class1"}},
{[]string{"class3", "class1", "class2"}, "value", "desc", []string{"class3", "class2", "class1"}},
// test sort by struct's method
{
[]TstX{{A: "i", B: "j"}, {A: "e", B: "f"}, {A: "c", B: "d"}, {A: "g", B: "h"}, {A: "a", B: "b"}},
"TstRv",
"asc",
[]TstX{{A: "a", B: "b"}, {A: "c", B: "d"}, {A: "e", B: "f"}, {A: "g", B: "h"}, {A: "i", B: "j"}},
},
{
[]*TstX{{A: "i", B: "j"}, {A: "e", B: "f"}, {A: "c", B: "d"}, {A: "g", B: "h"}, {A: "a", B: "b"}},
"TstRp",
"asc",
[]*TstX{{A: "a", B: "b"}, {A: "c", B: "d"}, {A: "e", B: "f"}, {A: "g", B: "h"}, {A: "i", B: "j"}},
},
// test map sorting by struct's method
{
map[string]TstX{"1": {A: "i", B: "j"}, "2": {A: "e", B: "f"}, "3": {A: "c", B: "d"}, "4": {A: "g", B: "h"}, "5": {A: "a", B: "b"}},
"TstRv",
"asc",
[]TstX{{A: "a", B: "b"}, {A: "c", B: "d"}, {A: "e", B: "f"}, {A: "g", B: "h"}, {A: "i", B: "j"}},
},
{
map[string]*TstX{"1": {A: "i", B: "j"}, "2": {A: "e", B: "f"}, "3": {A: "c", B: "d"}, "4": {A: "g", B: "h"}, "5": {A: "a", B: "b"}},
"TstRp",
"asc",
[]*TstX{{A: "a", B: "b"}, {A: "c", B: "d"}, {A: "e", B: "f"}, {A: "g", B: "h"}, {A: "i", B: "j"}},
},
// test sort by dot chaining key argument
{
[]map[string]TstX{{"foo": TstX{A: "e", B: "f"}}, {"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}},
"foo.A",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
[]map[string]TstX{{"foo": TstX{A: "e", B: "f"}}, {"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}},
".foo.A",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
[]map[string]TstX{{"foo": TstX{A: "e", B: "f"}}, {"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}},
"foo.TstRv",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
[]map[string]*TstX{{"foo": &TstX{A: "e", B: "f"}}, {"foo": &TstX{A: "a", B: "b"}}, {"foo": &TstX{A: "c", B: "d"}}},
"foo.TstRp",
"asc",
[]map[string]*TstX{{"foo": &TstX{A: "a", B: "b"}}, {"foo": &TstX{A: "c", B: "d"}}, {"foo": &TstX{A: "e", B: "f"}}},
},
{
[]map[string]mid{{"foo": mid{Tst: TstX{A: "e", B: "f"}}}, {"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}},
"foo.Tst.A",
"asc",
[]map[string]mid{{"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}, {"foo": mid{Tst: TstX{A: "e", B: "f"}}}},
},
{
[]map[string]mid{{"foo": mid{Tst: TstX{A: "e", B: "f"}}}, {"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}},
"foo.Tst.TstRv",
"asc",
[]map[string]mid{{"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}, {"foo": mid{Tst: TstX{A: "e", B: "f"}}}},
},
// test map sorting by dot chaining key argument
{
map[string]map[string]TstX{"1": {"foo": TstX{A: "e", B: "f"}}, "2": {"foo": TstX{A: "a", B: "b"}}, "3": {"foo": TstX{A: "c", B: "d"}}},
"foo.A",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
map[string]map[string]TstX{"1": {"foo": TstX{A: "e", B: "f"}}, "2": {"foo": TstX{A: "a", B: "b"}}, "3": {"foo": TstX{A: "c", B: "d"}}},
".foo.A",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
map[string]map[string]TstX{"1": {"foo": TstX{A: "e", B: "f"}}, "2": {"foo": TstX{A: "a", B: "b"}}, "3": {"foo": TstX{A: "c", B: "d"}}},
"foo.TstRv",
"asc",
[]map[string]TstX{{"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}, {"foo": TstX{A: "e", B: "f"}}},
},
{
map[string]map[string]*TstX{"1": {"foo": &TstX{A: "e", B: "f"}}, "2": {"foo": &TstX{A: "a", B: "b"}}, "3": {"foo": &TstX{A: "c", B: "d"}}},
"foo.TstRp",
"asc",
[]map[string]*TstX{{"foo": &TstX{A: "a", B: "b"}}, {"foo": &TstX{A: "c", B: "d"}}, {"foo": &TstX{A: "e", B: "f"}}},
},
{
map[string]map[string]mid{"1": {"foo": mid{Tst: TstX{A: "e", B: "f"}}}, "2": {"foo": mid{Tst: TstX{A: "a", B: "b"}}}, "3": {"foo": mid{Tst: TstX{A: "c", B: "d"}}}},
"foo.Tst.A",
"asc",
[]map[string]mid{{"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}, {"foo": mid{Tst: TstX{A: "e", B: "f"}}}},
},
{
map[string]map[string]mid{"1": {"foo": mid{Tst: TstX{A: "e", B: "f"}}}, "2": {"foo": mid{Tst: TstX{A: "a", B: "b"}}}, "3": {"foo": mid{Tst: TstX{A: "c", B: "d"}}}},
"foo.Tst.TstRv",
"asc",
[]map[string]mid{{"foo": mid{Tst: TstX{A: "a", B: "b"}}}, {"foo": mid{Tst: TstX{A: "c", B: "d"}}}, {"foo": mid{Tst: TstX{A: "e", B: "f"}}}},
},
// test error cases
{(*[]TstX)(nil), nil, "asc", false},
{TstX{A: "a", B: "b"}, nil, "asc", false},
{
[]map[string]TstX{{"foo": TstX{A: "e", B: "f"}}, {"foo": TstX{A: "a", B: "b"}}, {"foo": TstX{A: "c", B: "d"}}},
"foo.NotAvailable",
"asc",
false,
},
{
map[string]map[string]TstX{"1": {"foo": TstX{A: "e", B: "f"}}, "2": {"foo": TstX{A: "a", B: "b"}}, "3": {"foo": TstX{A: "c", B: "d"}}},
"foo.NotAvailable",
"asc",
false,
},
} {
var result interface{}
var err error
Expand All @@ -1133,12 +1254,19 @@ func TestSort(t *testing.T) {
} else {
result, err = Sort(this.sequence, this.sortByField, this.sortAsc)
}
if err != nil {
t.Errorf("[%d] failed: %s", i, err)
continue
}
if !reflect.DeepEqual(result, this.expect) {
t.Errorf("[%d] Sort called on sequence: %v | sortByField: `%v` | got %v but expected %v", i, this.sequence, this.sortByField, result, this.expect)

if b, ok := this.expect.(bool); ok && !b {
if err == nil {
t.Errorf("[%d] Sort didn't return an expected error", i)
}
} else {
if err != nil {
t.Errorf("[%d] failed: %s", i, err)
continue
}
if !reflect.DeepEqual(result, this.expect) {
t.Errorf("[%d] Sort called on sequence: %v | sortByField: `%v` | got %v but expected %v", i, this.sequence, this.sortByField, result, this.expect)
}
}
}
}
Expand Down

0 comments on commit 160bbb9

Please sign in to comment.