Drop does/did when turning a negative verb positive

src/3-three/verbs/api/api.js

@@ -12,6 +12,8 @@ import getSubject from './parse/getSubject.js'
 import getGrammar from './parse/grammar/index.js'
 import toNegative from './conjugate/toNegative.js'
 import { getTense } from './lib.js'
+import { inflect } from './conjugate/inflect.js'
+const keep = { tags: true }
 
 
 const api = function (View) {
@@ -146,6 +148,15 @@ const api = function (View) {
       if (m.found) {
         m.remove('do not')
       }
+      // 'does not walk' -> 'walks'
+      this.forEach(vb => {
+        const { root, auxiliary, negative } = parseVerb(vb)
+        if (negative.found && auxiliary.has('^(does|did)$')) {
+          const tense = auxiliary.has('did') ? 'PastTense' : 'PresentTense'
+          vb.replace(root, inflect(root, tense), keep).unTag('Infinitive').tag(tense)
+          vb.remove(auxiliary)
+        }
+      })
       return this.remove('#Negative')
     }
     toNegative(n) {

tests/three/sentences/negative-sentences.test.js

@@ -12,3 +12,13 @@ test('sentences.toPositive', function (t) {
 
   t.end()
 })
+
+test('sentences.toPositive does-not', function (t) {
+  const doc = nlp(`He does not like camels.`)
+  doc.sentences().toPositive()
+  t.equal(doc.text(), 'He likes camels.', here + 'does not')
+
+  doc.sentences().toNegative()
+  t.equal(doc.text(), 'He does not like camels.', here + 'back to neg')
+  t.end()
+})

tests/three/verbs/negation/to-positive.test.js

@@ -0,0 +1,30 @@
+import test from 'tape'
+import nlp from '../../_lib.js'
+const here = '[three/verb-toPositive] '
+
+test('inline verb toPositive:', function (t) {
+  const arr = [
+    [`he does not like camels`, 'he likes camels'],
+    [`he did not like camels`, 'he liked camels'],
+    [`he doesn't like camels`, 'he likes camels'],
+    [`she didn't go home`, 'she went home'],
+    [`it does not matter`, 'it matters'],
+    [`he does not have a car`, 'he has a car'],
+    [`he does not really like camels`, 'he really likes camels'],
+    [`spencer did not walk`, 'spencer walked'],
+    // already worked
+    [`they do not like camels`, 'they like camels'],
+    [`i do not like camels`, 'i like camels'],
+    [`do not use reverse psychology`, 'use reverse psychology'],
+    [`he is not cool`, 'he is cool'],
+    [`he will not go`, 'he will go'],
+    [`he has not eaten`, 'he has eaten'],
+  ]
+  arr.forEach(function (a) {
+    const doc = nlp(a[0])
+    doc.verbs().toPositive()
+    const str = doc.text('normal')
+    t.equal(str, a[1], here + a[1] + ' --- ' + str)
+  })
+  t.end()
+})