156 lines
3.2 KiB
Go
156 lines
3.2 KiB
Go
package version
|
|
|
|
import (
|
|
"fmt"
|
|
"regexp"
|
|
"strings"
|
|
)
|
|
|
|
// Constraint represents a single constraint for a version, such as
|
|
// ">= 1.0".
|
|
type Constraint struct {
|
|
f constraintFunc
|
|
check *Version
|
|
original string
|
|
}
|
|
|
|
// Constraints is a slice of constraints. We make a custom type so that
|
|
// we can add methods to it.
|
|
type Constraints []*Constraint
|
|
|
|
type constraintFunc func(v, c *Version) bool
|
|
|
|
var constraintOperators map[string]constraintFunc
|
|
|
|
var constraintRegexp *regexp.Regexp
|
|
|
|
func init() {
|
|
constraintOperators = map[string]constraintFunc{
|
|
"": constraintEqual,
|
|
"=": constraintEqual,
|
|
"!=": constraintNotEqual,
|
|
">": constraintGreaterThan,
|
|
"<": constraintLessThan,
|
|
">=": constraintGreaterThanEqual,
|
|
"<=": constraintLessThanEqual,
|
|
"~>": constraintPessimistic,
|
|
}
|
|
|
|
ops := make([]string, 0, len(constraintOperators))
|
|
for k, _ := range constraintOperators {
|
|
ops = append(ops, regexp.QuoteMeta(k))
|
|
}
|
|
|
|
constraintRegexp = regexp.MustCompile(fmt.Sprintf(
|
|
`^\s*(%s)\s*(%s)\s*$`,
|
|
strings.Join(ops, "|"),
|
|
VersionRegexpRaw))
|
|
}
|
|
|
|
// NewConstraint will parse one or more constraints from the given
|
|
// constraint string. The string must be a comma-separated list of
|
|
// constraints.
|
|
func NewConstraint(v string) (Constraints, error) {
|
|
vs := strings.Split(v, ",")
|
|
result := make([]*Constraint, len(vs))
|
|
for i, single := range vs {
|
|
c, err := parseSingle(single)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
result[i] = c
|
|
}
|
|
|
|
return Constraints(result), nil
|
|
}
|
|
|
|
// Check tests if a version satisfies all the constraints.
|
|
func (cs Constraints) Check(v *Version) bool {
|
|
for _, c := range cs {
|
|
if !c.Check(v) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
// Returns the string format of the constraints
|
|
func (cs Constraints) String() string {
|
|
csStr := make([]string, len(cs))
|
|
for i, c := range cs {
|
|
csStr[i] = c.String()
|
|
}
|
|
|
|
return strings.Join(csStr, ",")
|
|
}
|
|
|
|
// Check tests if a constraint is validated by the given version.
|
|
func (c *Constraint) Check(v *Version) bool {
|
|
return c.f(v, c.check)
|
|
}
|
|
|
|
func (c *Constraint) String() string {
|
|
return c.original
|
|
}
|
|
|
|
func parseSingle(v string) (*Constraint, error) {
|
|
matches := constraintRegexp.FindStringSubmatch(v)
|
|
if matches == nil {
|
|
return nil, fmt.Errorf("Malformed constraint: %s", v)
|
|
}
|
|
|
|
check, err := NewVersion(matches[2])
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return &Constraint{
|
|
f: constraintOperators[matches[1]],
|
|
check: check,
|
|
original: v,
|
|
}, nil
|
|
}
|
|
|
|
//-------------------------------------------------------------------
|
|
// Constraint functions
|
|
//-------------------------------------------------------------------
|
|
|
|
func constraintEqual(v, c *Version) bool {
|
|
return v.Equal(c)
|
|
}
|
|
|
|
func constraintNotEqual(v, c *Version) bool {
|
|
return !v.Equal(c)
|
|
}
|
|
|
|
func constraintGreaterThan(v, c *Version) bool {
|
|
return v.Compare(c) == 1
|
|
}
|
|
|
|
func constraintLessThan(v, c *Version) bool {
|
|
return v.Compare(c) == -1
|
|
}
|
|
|
|
func constraintGreaterThanEqual(v, c *Version) bool {
|
|
return v.Compare(c) >= 0
|
|
}
|
|
|
|
func constraintLessThanEqual(v, c *Version) bool {
|
|
return v.Compare(c) <= 0
|
|
}
|
|
|
|
func constraintPessimistic(v, c *Version) bool {
|
|
if v.LessThan(c) {
|
|
return false
|
|
}
|
|
|
|
for i := 0; i < c.si-1; i++ {
|
|
if v.segments[i] != c.segments[i] {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|