Correctly handle prereleases/ANY ranges in subset

An "ANY" range (ie, `""`, `*`, etc.) does not include prerelease
versions except when `includePrerelease` flag is set.

Also, merely looking at the max/min boundaries of any ranges ignores the
fact that the sub range maybe including prerelease versions that are
excluded from the super range.  For example, `>=1.2.3-pre.0` is _not_ a
subset of `>=1.0.0`, because it inludes `1.2.3-pre.0`, `1.2.3-pre.1`,
and so on.

PR-URL: #377
Credit: @isaacs
Close: #377
Reviewed-by: @wraithgar

ranges/subset.js

@@ -1,22 +1,28 @@
 const Range = require('../classes/range.js')
-const { ANY } = require('../classes/comparator.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 subset of some `R1, R2, ...`
+// - 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
-//   - return true
 // - If c is only the ANY comparator
 //   - If C is only the ANY comparator, return true
-//   - Else return false
+//   - 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)
@@ -25,13 +31,16 @@ const compare = require('../functions/compare.js')
 // - 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 any C is a = range, and GT or LT are set, 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) => {
+const subset = (sub, dom, options = {}) => {
   if (sub === dom)
     return true
 
@@ -60,11 +69,21 @@ const simpleSubset = (sub, dom, options) => {
   if (sub === dom)
     return true
 
-  if (dom.length === 1 && dom[0].semver === ANY)
-    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 (sub.length === 1 && sub[0].semver === ANY)
-    return dom.length === 1 && dom[0].semver === ANY
+  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
@@ -107,10 +126,32 @@ const simpleSubset = (sub, dom, options) => {
 
   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)
@@ -119,6 +160,14 @@ const simpleSubset = (sub, dom, 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)
@@ -139,6 +188,12 @@ const simpleSubset = (sub, dom, options) => {
   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
 }
 

test/ranges/subset.js

@@ -18,9 +18,26 @@ const cases = [
   // everything is a subset of *
   ['1.2.3', '*', true],
   ['^1.2.3', '*', true],
-  ['^1.2.3-pre.0', '*', true],
+  ['^1.2.3-pre.0', '*', false],
+  ['^1.2.3-pre.0', '*', true, { includePrerelease: true }],
   ['1 || 2 || 3', '*', true],
 
+  // prerelease edge cases
+  ['^1.2.3-pre.0', '>=1.0.0', false],
+  ['^1.2.3-pre.0', '>=1.0.0', true, { includePrerelease: true }],
+  ['^1.2.3-pre.0', '>=1.2.3-pre.0', true],
+  ['^1.2.3-pre.0', '>=1.2.3-pre.0', true, { includePrerelease: true }],
+  ['>1.2.3-pre.0', '>=1.2.3-pre.0', true],
+  ['>1.2.3-pre.0', '>1.2.3-pre.0 || 2', true],
+  ['1 >1.2.3-pre.0', '>1.2.3-pre.0', true],
+  ['1 <=1.2.3-pre.0', '>=1.0.0-0', false],
+  ['1 <=1.2.3-pre.0', '>=1.0.0-0', true, { includePrerelease: true }],
+  ['1 <=1.2.3-pre.0', '<=1.2.3-pre.0', true],
+  ['1 <=1.2.3-pre.0', '<=1.2.3-pre.0', true, { includePrerelease: true }],
+  ['<1.2.3-pre.0', '<=1.2.3-pre.0', true],
+  ['<1.2.3-pre.0', '<1.2.3-pre.0 || 2', true],
+  ['1 <1.2.3-pre.0', '<1.2.3-pre.0', true],
+
   ['*', '*', true],
   ['', '*', true],
   ['*', '', true],
@@ -29,9 +46,16 @@ const cases = [
   // >=0.0.0 is like * in non-prerelease mode
   // >=0.0.0-0 is like * in prerelease mode
   ['*', '>=0.0.0-0', true, { includePrerelease: true }],
+
+  // true because these are identical in non-PR mode
   ['*', '>=0.0.0', true],
+
+  // false because * includes 0.0.0-0 in PR mode
   ['*', '>=0.0.0', false, { includePrerelease: true }],
-  ['*', '>=0.0.0-0', false],
+
+  // true because * doesn't include 0.0.0-0 in non-PR mode
+  ['*', '>=0.0.0-0', true],
+
   ['^2 || ^3 || ^4', '>=1', true],
   ['^2 || ^3 || ^4', '>1', true],
   ['^2 || ^3 || ^4', '>=2', true],
@@ -79,9 +103,8 @@ const cases = [
   ['>2.0.0', '>=2.0.0', true],
 ]
 
-
 t.plan(cases.length + 1)
-cases.forEach(([sub, dom, expect, options = {}]) => {
+cases.forEach(([sub, dom, expect, options]) => {
   const msg = `${sub || "''"} ⊂ ${dom || "''"} = ${expect}` +
     (options ? ' ' + Object.keys(options).join(',') : '')
   t.equal(subset(sub, dom, options), expect, msg)