fix: optional set calc

Author: liamcmitchell

workspaces/arborist/lib/optional-set.js

@@ -29,10 +29,8 @@ const optionalSet = node => {
   }
 
   // now that we've hit the boundary, gather the rest of the nodes in
-  // the optional section.  that's the set of dependencies that are only
-  // depended upon by other nodes within the set, or optional dependencies
-  // from outside the set.
-  return gatherDepSet(set, edge => !edge.optional)
+  // the optional section that don't have dependents outside the set.
+  return gatherDepSet(set, edge => !set.has(edge.to))
 }
 
 module.exports = optionalSet

workspaces/arborist/test/optional-set.js

@@ -9,8 +9,8 @@ tree (PROD a, PROD c, OPT i)
 +-- a (OPT o)
 +-- b (PROD c)
 +-- c (OPT b)
-+-- o (PROD m)
-+-- m (PROD n)
++-- o (PROD m, OPT i)
++-- m (OPT n)
 +-- n ()
 +-- OPT i (PROD j)
 +-- j ()
@@ -38,8 +38,8 @@ const tree = new Node({
     ['a', [], ['o']],
     ['b', ['c'], []],
     ['c', [], ['b']],
-    ['o', ['m'], []],
-    ['m', ['n'], []],
+    ['o', ['m'], ['i']],
+    ['m', [], ['n']],
     ['n', [], []],
     ['i', ['j'], []],
     ['j', [], []],
@@ -83,12 +83,6 @@ t.equal(setO.has(nodeO), true, 'set o includes o')
 t.equal(setO.has(nodeM), true, 'set o includes m')
 t.equal(setO.has(nodeN), true, 'set o includes n')
 
-const setN = optionalSet(nodeO)
-t.equal(setN.size, 3, 'three nodes in n set')
-t.equal(setN.has(nodeO), true, 'set n includes o')
-t.equal(setN.has(nodeM), true, 'set n includes m')
-t.equal(setN.has(nodeN), true, 'set n includes n')
-
 const setB = optionalSet(nodeB)
 t.equal(setB.size, 1, 'gathering from b is only b')
 t.equal(setB.has(nodeB), true, 'set b includes b')