Matching results disappear when expending the term

Hi Oliver,

I am working with lunr since a couple of week (which I have to say is awesome in term of easy to use, and features). I am having a strange behavior who seems to be similar to something already described in this issue #68

I have entries some containing phone, others containing iphone. If I search for phon, both phone and iphone entries are returned. If I search for phone, only phone entries are returned.

I am using leading and trailing wildcard on term :

q.term(term, {
    boost: 100
})

q.term(term, {
     boost: 10,
     usePipeline: false,
     wildcard: lunr.Query.wildcard.LEADING | lunr.Query.wildcard.TRAILING
})

I tried by adding only with leading wildcard, but results are the same. It can be easily reproduce with this code :

const lunr = require('lunr')
const data = [{name: 'phone'}, {name: 'iphone'}]
const index = lunr(function () {
  this.ref('name')
  this.field('name')
  data.forEach(item => this.add(item))
})

index.search('phone')
// [ { ref: 'phone', score: 1, matchData: { metadata: [Object] } } ]
index.search('iphone')
// [ { ref: 'iphone', score: 1, matchData: { metadata: [Object] } } ]
index.search('*phone')
// [ { ref: 'phone', score: 1, matchData: { metadata: [Object] } } ]
index.search('*phon')
// [ { ref: 'iphone', score: 1, matchData: { metadata: [Object] } } ]

Am I missing something, or is this a bug ? If it’s one, how can I help to solve it ?

Thanks a lot.

[olivernn]

@myalgo @mike1808 the test I just added.

[olivernn]

@gsavin yeah, stemming is a bit of a black box, I didn’t write the current stemmer, so its even more of a black box. I did think about re-implementing it, if nothing else then to understand the rules a bit more, but time is always in short supply!

@mike1808 regarding the behaviour of the wildcard, I think that is a bug, or at least incorrectly implemented. I took inspiration for the syntax from Lucene and its * matches 0 or more, where it looks like Lunr implements it as 1 or more. I’ll take a look at what would be involved in fixing this.