CasperSecurity
const Range = require('../classes/range.js')
const Comparator = require('../classes/comparator.js')
const { ANY } = Comparator
const satisfies = require('../functions/satisfies.js')
const compare = require('../functions/compare.js')
// Complex range `r1 || r2 || ...` is a subset of `R1 || R2 || ...` iff:
// - Every simple range `r1, r2, ...` is a null set, OR
// - Every simple range `r1, r2, ...` which is not a null set is a subset of
// some `R1, R2, ...`
//
// Simple range `c1 c2 ...` is a subset of simple range `C1 C2 ...` iff:
// - If c is only the ANY comparator
// - If C is only the ANY comparator, return true
// - Else if in prerelease mode, return false
// - else replace c with `[>=0.0.0]`
// - If C is only the ANY comparator
// - if in prerelease mode, return true
// - else replace C with `[>=0.0.0]`
// - Let EQ be the set of = comparators in c
// - If EQ is more than one, return true (null set)
// - Let GT be the highest > or >= comparator in c
// - Let LT be the lowest < or <= comparator in c
// - If GT and LT, and GT.semver > LT.semver, return true (null set)
// - If any C is a = range, and GT or LT are set, return false
// - If EQ
// - If GT, and EQ does not satisfy GT, return true (null set)
// - If LT, and EQ does not satisfy LT, return true (null set)
// - If EQ satisfies every C, return true
// - Else return false
// - If GT
// - If GT.semver is lower than any > or >= comp in C, return false
// - If GT is >=, and GT.semver does not satisfy every C, return false
// - If GT.semver has a prerelease, and not in prerelease mode
// - If no C has a prerelease and the GT.semver tuple, return false
// - If LT
// - If LT.semver is greater than any < or <= comp in C, return false
// - If LT is <=, and LT.semver does not satisfy every C, return false
// - If GT.semver has a prerelease, and not in prerelease mode
// - If no C has a prerelease and the LT.semver tuple, return false
// - Else return true
const subset = (sub, dom, options = {}) => {
if (sub === dom)
return true
sub = new Range(sub, options)
dom = new Range(dom, options)
let sawNonNull = false
OUTER: for (const simpleSub of sub.set) {
for (const simpleDom of dom.set) {
const isSub = simpleSubset(simpleSub, simpleDom, options)
sawNonNull = sawNonNull || isSub !== null
if (isSub)
continue OUTER
}
// the null set is a subset of everything, but null simple ranges in
// a complex range should be ignored. so if we saw a non-null range,
// then we know this isn't a subset, but if EVERY simple range was null,
// then it is a subset.
if (sawNonNull)
return false
}
return true
}
const simpleSubset = (sub, dom, options) => {
if (sub === dom)
return true
if (sub.length === 1 && sub[0].semver === ANY) {
if (dom.length === 1 && dom[0].semver === ANY)
return true
else if (options.includePrerelease)
sub = [ new Comparator('>=0.0.0-0') ]
else
sub = [ new Comparator('>=0.0.0') ]
}
if (dom.length === 1 && dom[0].semver === ANY) {
if (options.includePrerelease)
return true
else
dom = [ new Comparator('>=0.0.0') ]
}
const eqSet = new Set()
let gt, lt
for (const c of sub) {
if (c.operator === '>' || c.operator === '>=')
gt = higherGT(gt, c, options)
else if (c.operator === '<' || c.operator === '<=')
lt = lowerLT(lt, c, options)
else
eqSet.add(c.semver)
}
if (eqSet.size > 1)
return null
let gtltComp
if (gt && lt) {
gtltComp = compare(gt.semver, lt.semver, options)
if (gtltComp > 0)
return null
else if (gtltComp === 0 && (gt.operator !== '>=' || lt.operator !== '<='))
return null
}
// will iterate one or zero times
for (const eq of eqSet) {
if (gt && !satisfies(eq, String(gt), options))
return null
if (lt && !satisfies(eq, String(lt), options))
return null
for (const c of dom) {
if (!satisfies(eq, String(c), options))
return false
}
return true
}
let higher, lower
let hasDomLT, hasDomGT
// if the subset has a prerelease, we need a comparator in the superset
// with the same tuple and a prerelease, or it's not a subset
let needDomLTPre = lt &&
!options.includePrerelease &&
lt.semver.prerelease.length ? lt.semver : false
let needDomGTPre = gt &&
!options.includePrerelease &&
gt.semver.prerelease.length ? gt.semver : false
// exception: <1.2.3-0 is the same as <1.2.3
if (needDomLTPre && needDomLTPre.prerelease.length === 1 &&
lt.operator === '<' && needDomLTPre.prerelease[0] === 0) {
needDomLTPre = false
}
for (const c of dom) {
hasDomGT = hasDomGT || c.operator === '>' || c.operator === '>='
hasDomLT = hasDomLT || c.operator === '<' || c.operator === '<='
if (gt) {
if (needDomGTPre) {
if (c.semver.prerelease && c.semver.prerelease.length &&
c.semver.major === needDomGTPre.major &&
c.semver.minor === needDomGTPre.minor &&
c.semver.patch === needDomGTPre.patch) {
needDomGTPre = false
}
}
if (c.operator === '>' || c.operator === '>=') {
higher = higherGT(gt, c, options)
if (higher === c && higher !== gt)
return false
} else if (gt.operator === '>=' && !satisfies(gt.semver, String(c), options))
return false
}
if (lt) {
if (needDomLTPre) {
if (c.semver.prerelease && c.semver.prerelease.length &&
c.semver.major === needDomLTPre.major &&
c.semver.minor === needDomLTPre.minor &&
c.semver.patch === needDomLTPre.patch) {
needDomLTPre = false
}
}
if (c.operator === '<' || c.operator === '<=') {
lower = lowerLT(lt, c, options)
if (lower === c && lower !== lt)
return false
} else if (lt.operator === '<=' && !satisfies(lt.semver, String(c), options))
return false
}
if (!c.operator && (lt || gt) && gtltComp !== 0)
return false
}
// if there was a < or >, and nothing in the dom, then must be false
// UNLESS it was limited by another range in the other direction.
// Eg, >1.0.0 <1.0.1 is still a subset of <2.0.0
if (gt && hasDomLT && !lt && gtltComp !== 0)
return false
if (lt && hasDomGT && !gt && gtltComp !== 0)
return false
// we needed a prerelease range in a specific tuple, but didn't get one
// then this isn't a subset. eg >=1.2.3-pre is not a subset of >=1.0.0,
// because it includes prereleases in the 1.2.3 tuple
if (needDomGTPre || needDomLTPre)
return false
return true
}
// >=1.2.3 is lower than >1.2.3
const higherGT = (a, b, options) => {
if (!a)
return b
const comp = compare(a.semver, b.semver, options)
return comp > 0 ? a
: comp < 0 ? b
: b.operator === '>' && a.operator === '>=' ? b
: a
}
// <=1.2.3 is higher than <1.2.3
const lowerLT = (a, b, options) => {
if (!a)
return b
const comp = compare(a.semver, b.semver, options)
return comp < 0 ? a
: comp > 0 ? b
: b.operator === '<' && a.operator === '<=' ? b
: a
}
module.exports = subset