My test class (not annotated seeAllData=true) actually sees data for ContentNote SObject

Question

I know test methods should not see any data except the data created in test context, but when I run the test below, the query returns an org record.

It should not

I have a REST class like

@RestResource(urlMapping='/path/to/*')
global with sharing class MyRest {
    @HttpPost
    global static String executePost(){
        String command = RestContext.request.requestUri.split('/')[3];
        if (command == 'conf')
        {
            return noteConf(RestContext.request.requestBody);
        }
        // irrelevant code here...
    }

private static String noteConf(Blob requestBody){
        String title = 'Check connected app';
        ContentNote[] ln = [Select Id, Title, Content from ContentNote where Title = :title];
        ContentNote n;
        if (ln.size()>0) {
            n = ln[0];
        }
        else{
            n = new ContentNote();
            n.Title = title;
        }
        n.Content = requestBody;
        upsert n;
        return n.Id;
   }

My test method is :

@isTest(seeAllData=false)
    static void test_note(){
        Test.startTest();
        RestRequest req = new RestRequest(); 
        RestResponse res = new RestResponse();
        req.requestURI = '/path/to/conf';
        req.httpMethod = 'POST';
        req.requestBody = Blob.valueOf('the note content !');
        RestContext.request = req;
        RestContext.response= res;
        String s = MyRest.executePost();    //First call, a note should be created
        Id i = (Id) s;    //checks it's an Id (if not an Exception will be thrown)
        String t = MyRest.executePost();    //call it again to check a 2nd note is not created
        System.assertEquals(i, (Id) t);
        Test.stopTest();
    }

I expect the first SOQL query in noteConf method to return 0 record, and the second one to return 1.

But it does

But there already is in my org a ContentNote with title 'Check connected app', the 1st query returns this record. I can't figure out why ?

The seeAllData=false was not there at the beggining, it's the default. Adding it didn't change anything.

Here is the log of the 1st call :

19:01:31.3 (16682032)|SOQL_EXECUTE_BEGIN|[50]|Aggregations:0|SELECT Id, Title, Content FROM ContentNote WHERE Title = :tmpVar1
19:01:31.3 (48338272)|SOQL_EXECUTE_END|[50]|Rows:1
19:01:31.3 (48381399)|HEAP_ALLOCATE|[50]|Bytes:8
19:01:31.3 (48412157)|HEAP_ALLOCATE|[50]|Bytes:329
19:01:31.3 (48547547)|HEAP_ALLOCATE|[50]|Bytes:8
19:01:31.3 (48579122)|VARIABLE_SCOPE_BEGIN|[50]|ln|List<ContentNote>|true|false
19:01:31.3 (48653446)|VARIABLE_ASSIGNMENT|[50]|ln|[{"Id":"0693E000000hfsIQAQ","Title":"Check connected app","LatestContentId":"05T3E000002GTDjUAO","LatestPublishedVersionId":"0683E000000hadgQAA","Content":BLOB(178 bytes)}]|0x26e3554

Wondering if the ContentNote object could have a different behaviour and been always seen, I added this code right after the SOQL query :

Contact[] lc = [Select Id from Contact];
System.debug(lc.size());

which returned 0 while, obviously, there are contacts in my org. That might be a clue...

I checked Salesforce documentation but but did not find anything about that, any help or explanation would be appreciated.

Answer 1

I know test methods should not see any data except the data created in test context...

This is untrue. Certain types of metadata are exposed in unit tests. Isolation of Test Data from Organization Data in Unit Tests says:

However, objects that are used to manage your organization or metadata objects can still be accessed in your tests such as:

And goes on to list a sampling of objects that ignore database isolation in unit tests, such as ApexClass and User. While ContentNote is not specified on this list, it is apparently one of those types that fall in this category. You will need to delete the record in your unit test in order to then recreate it.