hugo/tpl/compare/compare.go
acclassic f95fd57aac
tpl/compare: Sort special float values as string
When sorting strings a worng order is returned. This happens because the strings are first converted
to floating values to check whether or not they should be sorted as
floating values. When an error is returned the strings will be
handled as string literals.
No error will be returned when parsing Inf, Infinity or NaN (case insensitive) because they
will be coverted to special floating point values and therefore are
legal float values.
Now we check if the returned converted values are special floating
values and treat them as string literals.

Fixes #10389
2023-01-02 17:35:08 +01:00

356 lines
8.9 KiB
Go

// Copyright 2017 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package compare provides template functions for comparing values.
package compare
import (
"fmt"
"math"
"reflect"
"strconv"
"time"
"github.com/gohugoio/hugo/compare"
"github.com/gohugoio/hugo/langs"
"github.com/gohugoio/hugo/common/hreflect"
"github.com/gohugoio/hugo/common/htime"
"github.com/gohugoio/hugo/common/types"
)
// New returns a new instance of the compare-namespaced template functions.
func New(loc *time.Location, caseInsensitive bool) *Namespace {
return &Namespace{loc: loc, caseInsensitive: caseInsensitive}
}
// Namespace provides template functions for the "compare" namespace.
type Namespace struct {
loc *time.Location
// Enable to do case insensitive string compares.
caseInsensitive bool
}
// Default checks whether a givenv is set and returns the default value defaultv if it
// is not. "Set" in this context means non-zero for numeric types and times;
// non-zero length for strings, arrays, slices, and maps;
// any boolean or struct value; or non-nil for any other types.
func (*Namespace) Default(defaultv any, givenv ...any) (any, error) {
// given is variadic because the following construct will not pass a piped
// argument when the key is missing: {{ index . "key" | default "foo" }}
// The Go template will complain that we got 1 argument when we expected 2.
if len(givenv) == 0 {
return defaultv, nil
}
if len(givenv) != 1 {
return nil, fmt.Errorf("wrong number of args for default: want 2 got %d", len(givenv)+1)
}
g := reflect.ValueOf(givenv[0])
if !g.IsValid() {
return defaultv, nil
}
set := false
switch g.Kind() {
case reflect.Bool:
set = true
case reflect.String, reflect.Array, reflect.Slice, reflect.Map:
set = g.Len() != 0
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
set = g.Int() != 0
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
set = g.Uint() != 0
case reflect.Float32, reflect.Float64:
set = g.Float() != 0
case reflect.Complex64, reflect.Complex128:
set = g.Complex() != 0
case reflect.Struct:
switch actual := givenv[0].(type) {
case time.Time:
set = !actual.IsZero()
default:
set = true
}
default:
set = !g.IsNil()
}
if set {
return givenv[0], nil
}
return defaultv, nil
}
// Eq returns the boolean truth of arg1 == arg2 || arg1 == arg3 || arg1 == arg4.
func (n *Namespace) Eq(first any, others ...any) bool {
if n.caseInsensitive {
panic("caseInsensitive not implemented for Eq")
}
n.checkComparisonArgCount(1, others...)
normalize := func(v any) any {
if types.IsNil(v) {
return nil
}
if at, ok := v.(htime.AsTimeProvider); ok {
return at.AsTime(n.loc)
}
vv := reflect.ValueOf(v)
switch vv.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
return vv.Int()
case reflect.Float32, reflect.Float64:
return vv.Float()
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
return vv.Uint()
case reflect.String:
return vv.String()
default:
return v
}
}
normFirst := normalize(first)
for _, other := range others {
if e, ok := first.(compare.Eqer); ok {
if e.Eq(other) {
return true
}
continue
}
if e, ok := other.(compare.Eqer); ok {
if e.Eq(first) {
return true
}
continue
}
other = normalize(other)
if reflect.DeepEqual(normFirst, other) {
return true
}
}
return false
}
// Ne returns the boolean truth of arg1 != arg2 && arg1 != arg3 && arg1 != arg4.
func (n *Namespace) Ne(first any, others ...any) bool {
n.checkComparisonArgCount(1, others...)
for _, other := range others {
if n.Eq(first, other) {
return false
}
}
return true
}
// Ge returns the boolean truth of arg1 >= arg2 && arg1 >= arg3 && arg1 >= arg4.
func (n *Namespace) Ge(first any, others ...any) bool {
n.checkComparisonArgCount(1, others...)
for _, other := range others {
left, right := n.compareGet(first, other)
if !(left >= right) {
return false
}
}
return true
}
// Gt returns the boolean truth of arg1 > arg2 && arg1 > arg3 && arg1 > arg4.
func (n *Namespace) Gt(first any, others ...any) bool {
n.checkComparisonArgCount(1, others...)
for _, other := range others {
left, right := n.compareGet(first, other)
if !(left > right) {
return false
}
}
return true
}
// Le returns the boolean truth of arg1 <= arg2 && arg1 <= arg3 && arg1 <= arg4.
func (n *Namespace) Le(first any, others ...any) bool {
n.checkComparisonArgCount(1, others...)
for _, other := range others {
left, right := n.compareGet(first, other)
if !(left <= right) {
return false
}
}
return true
}
// Lt returns the boolean truth of arg1 < arg2 && arg1 < arg3 && arg1 < arg4.
// The provided collator will be used for string comparisons.
// This is for internal use.
func (n *Namespace) LtCollate(collator *langs.Collator, first any, others ...any) bool {
n.checkComparisonArgCount(1, others...)
for _, other := range others {
left, right := n.compareGetWithCollator(collator, first, other)
if !(left < right) {
return false
}
}
return true
}
// Lt returns the boolean truth of arg1 < arg2 && arg1 < arg3 && arg1 < arg4.
func (n *Namespace) Lt(first any, others ...any) bool {
return n.LtCollate(nil, first, others...)
}
func (n *Namespace) checkComparisonArgCount(min int, others ...any) bool {
if len(others) < min {
panic("missing arguments for comparison")
}
return true
}
// Conditional can be used as a ternary operator.
//
// It returns v1 if cond is true, else v2.
func (n *Namespace) Conditional(cond bool, v1, v2 any) any {
if cond {
return v1
}
return v2
}
func (ns *Namespace) compareGet(a any, b any) (float64, float64) {
return ns.compareGetWithCollator(nil, a, b)
}
func (ns *Namespace) compareGetWithCollator(collator *langs.Collator, a any, b any) (float64, float64) {
if ac, ok := a.(compare.Comparer); ok {
c := ac.Compare(b)
if c < 0 {
return 1, 0
} else if c == 0 {
return 0, 0
} else {
return 0, 1
}
}
if bc, ok := b.(compare.Comparer); ok {
c := bc.Compare(a)
if c < 0 {
return 0, 1
} else if c == 0 {
return 0, 0
} else {
return 1, 0
}
}
var left, right float64
var leftStr, rightStr *string
av := reflect.ValueOf(a)
switch av.Kind() {
case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
left = float64(av.Len())
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
left = float64(av.Int())
case reflect.Float32, reflect.Float64:
left = av.Float()
case reflect.String:
var err error
left, err = strconv.ParseFloat(av.String(), 64)
// Check if float is a special floating value and cast value as string.
if math.IsInf(left, 0) || math.IsNaN(left) || err != nil {
str := av.String()
leftStr = &str
}
case reflect.Struct:
if hreflect.IsTime(av.Type()) {
left = float64(ns.toTimeUnix(av))
}
case reflect.Bool:
left = 0
if av.Bool() {
left = 1
}
}
bv := reflect.ValueOf(b)
switch bv.Kind() {
case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice:
right = float64(bv.Len())
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
right = float64(bv.Int())
case reflect.Float32, reflect.Float64:
right = bv.Float()
case reflect.String:
var err error
right, err = strconv.ParseFloat(bv.String(), 64)
// Check if float is a special floating value and cast value as string.
if math.IsInf(right, 0) || math.IsNaN(right) || err != nil {
str := bv.String()
rightStr = &str
}
case reflect.Struct:
if hreflect.IsTime(bv.Type()) {
right = float64(ns.toTimeUnix(bv))
}
case reflect.Bool:
right = 0
if bv.Bool() {
right = 1
}
}
if (ns.caseInsensitive || collator != nil) && leftStr != nil && rightStr != nil {
var c int
if collator != nil {
c = collator.CompareStrings(*leftStr, *rightStr)
} else {
c = compare.Strings(*leftStr, *rightStr)
}
if c < 0 {
return 0, 1
} else if c > 0 {
return 1, 0
} else {
return 0, 0
}
}
switch {
case leftStr == nil || rightStr == nil:
case *leftStr < *rightStr:
return 0, 1
case *leftStr > *rightStr:
return 1, 0
default:
return 0, 0
}
return left, right
}
func (ns *Namespace) toTimeUnix(v reflect.Value) int64 {
t, ok := hreflect.AsTime(v, ns.loc)
if !ok {
panic("coding error: argument must be time.Time type reflect Value")
}
return t.Unix()
}