fix for obscure runtime error in capture-group

changelog.md

@@ -12,6 +12,11 @@ While all _Major_ releases should be reviewed, our only two _large_ releases are
 
 -->
 
+#### 13.11.1 [April 2021]
+
+- **[fix]** - obscure runtime error in capture-groups
+  _plugin-releases_: typeahead
+
 #### 13.11.0 [April 2021]
 
 - **[change]** - use babel default build target (drop ie11 polyfill)

package.json

@@ -2,7 +2,7 @@
   "author": "Spencer Kelly <spencermountain@gmail.com> (http://spencermounta.in)",
   "name": "compromise",
   "description": "modest natural language processing",
-  "version": "13.11.0",
+  "version": "13.11.1",
   "main": "./builds/compromise.js",
   "unpkg": "./builds/compromise.min.js",
   "module": "./builds/compromise.mjs",

scratch.js

@@ -9,31 +9,8 @@ nlp.extend(require('./plugins/typeahead/src'))
 // nlp.verbose(true)
 
 // runtime error:
-/*
 let doc = nlp(`to foo`)
-let m = doc.match('[.+] to', 0)
-console.log(m)
-m.clone().debug()
-*/
-
-// create a newton plugin
-const plugin = function (_Doc, world, _nlp) {
-  let obj = {
-    size: 2,
-    words: {
-      july: 'Month',
-      august: 'Month',
-      september: 'Month',
-    },
-  }
-  _nlp.typeahead(obj.words, { min: obj.size, safe: false })
-}
-nlp.extend(plugin)
-let doc = nlp('20 septem')
-doc.autoFill()
-doc.debug()
-console.log(doc.termList(1))
-console.log(doc.dates().get())
+// let m = doc.match('[.+] to').debug()
 
 // doc.clone().dates()
 // console.log(doc.text())

src/Phrase/match/03-tryMatch.js

@@ -47,6 +47,10 @@ const tryHere = function (terms, regs, start_i, phrase_length) {
     //support 'unspecific greedy' .* properly
     if (reg.anything === true && reg.greedy === true) {
       let skipto = logic.greedyTo(state, regs[state.r + 1])
+      //maybe we couldn't find it
+      if (skipto === null || skipto === 0) {
+        return null
+      }
       // ensure it's long enough
       if (reg.min !== undefined && skipto - state.t < reg.min) {
         return null
@@ -56,9 +60,6 @@ const tryHere = function (terms, regs, start_i, phrase_length) {
         state.t = state.t + reg.max
         continue
       }
-      if (skipto === null) {
-        return null //couldn't find it
-      }
       // is it really this easy?....
       if (state.hasGroup === true) {
         const g = logic.getGroup(state, state.t, reg.named)

tests/match/capture.test.js

@@ -49,5 +49,15 @@ test('tricky capture', function (t) {
   let doc = nlp.tokenize('during august')
   let m = doc.match('^(on|during|in) [.]', 0)
   t.equal(m.text('normal'), 'august', 'found capture')
+
+  // test for this weird non-match
+  doc = nlp(`to foo`)
+  m = doc.match('[.+] to')
+  t.equal(m.text(), '', 'optional-group not found')
+  // this is a creepy bug
+  m = doc.match('[.+] to', 0)
+  m.clone().text()
+  t.ok(true, 'creepy-group bug')
+
   t.end()
 })