undefined in "searchResults" but present in "rawResults"

Hi Luca,

me again^^

I have the following, quite strange behaviour.

You can add entries to the list of elements, that can be searched with mini-search. While you add the new entry, the query stays active.

The result should be, if the new entry matches the query, it should be displayed.

So, if the input data changes I perform search via a useEffect hook and display the new data.

But what happens is that despite having a match in the raw results (correct field, correct match, everything ok), the entry in searchResult is undefined causing a crash.

   useEffect(() => {
        if (data && !isFirstRender.current) {
            removeAll();
            addAll(data);
        }

        isFirstRender.current = false;

    }, [data]);

    useEffect(() => {
        if (data) {
            search(filter.query, {
                filter: filterOptions.categoryField && filter.categories.length > 0 ? matchCategory : undefined,
            });
        }
    }, [data, filter, filterOptions, matchCategory]);

The order of execution is correct, double checked on that.

Result looks like:

rawResults

[
    {
        "id": "6a901953144c411580520ed07B4567",
        "terms": [
            "einholung"
        ],
        "score": 8.600445452294665,
        "match": {
            "einholung": [
                "custom.bezeichnung"
            ]
        },
        "custom.kategorien": [
            "Gefahr in Verzug",
            "Sicherheit",
            "Qualität"
        ]
    },
    {
        "id": "h1662s",
        "terms": [
            "einholungsbums"
        ],
        "score": 4.152082359120152,
        "match": {
            "einholungsbums": [
                "custom.bezeichnung"
            ]
        },
        "custom.kategorien": [
            "Gefahr in Verzug"
        ]
    }
]

[
    {
        "id": "6a901953144c411580520ed07B4567",
        "datum": "2020-09-17T20:34:56.170914Z",
        "custom": {
            "id": "6a901953144c411580520ed07a21ef39",
            "erstelldatum": "2020-09-17T20:34:56.170914Z",
            "baumassnahmenId": "45042621",
            "bezeichnung": "Einholung weiterer Informationen",
            "kategorien": [
                "Gefahr in Verzug",
                "Sicherheit",
                "Qualität"
            ],
    .....
    },
    undefined -> Where the second element should be.
]

Help would be highly appreciated. I’m kind of confused…

[florianmatz]

Hi Luca:

Here you go: https://codepen.io/florianmatz/pen/xxqEaGE?

Steps to reproduce:

• Codepen’s console
• Enter “Zum Testen” into the search field (“Enter query”)
• You’ll get a “No results” warning
• Now switch the dataset; choose “Dataset 1” from select
• App crashes -> discrepancy between rawResults and searchResults (see console) as described in the issue

What’s completely weird:

If you switch the datasets BEFORE you perform the reproduction steps, it works like a charm. So, what’s important to reproduce: Only with data, that has not been indexed before… So make sure you’ve reloaded the codepen before testing it.

Here you find a short screen recording, if my description was too confusing… 😃 https://we.tl/t-3Xpiz6bMq6

It kind of seems, that the indexing is done, but the mapping of terms -> results is not ready yet… (if that makes any sense at all 😛)

[lucaong]

Great news @florianmatz , the problem was indeed in react-minisearch. It was using useState instead of useRef to store local values such as the map of documents by ID: the problem is that setting the state is asynchronous, while adding/removing things to the index is synchronous by default. Therefore, the effective order of update of the index and the map of documents by ID was swapped, and under certain conditions this would surface as the bug you found.

The new version 3.0.3 of react-minisearch fixes the problem, and seems to work well with your app: https://codepen.io/lucaong/pen/yLMVxxy

Thanks again for reporting this, and for the reproduction example on codepen! I am closing the issue, but feel free to comment on it if you find out that it is not completely solved.