Cannot query for related objects where the relation is NULL.

[tomasreimers]

Issue Description

Cannot query for related objects where the relation is NULL.

For example,

prod.manager.find(Book, {
where: {
author: IsNull(),
},
relations: ["author"],
})

Will simply query for all books (not adding any where relationship for "authorId IS NULL").

Expected Behavior

We would add the relationship of "authorId IS NULL".

Actual Behavior

We do not add the relationship of "authorId IS NULL".

Steps to Reproduce

1. Create author table
2. Create book table

prod.manager.find(Book, {
        where: {
          author: IsNull(),
        },
        relations: ["author"],
      })

My Environment

MacOS, TypeORM 0.35

Relevant Database Driver(s)

Postgres

Are you willing to resolve this issue by submitting a Pull Request?

• ✖️ Yes, I have the time, and I know how to start.
• ✅ Yes, I have the time, but I don't know how to start. I would need guidance.
• ✖️ No, I don’t have the time, but I can support (using donations) development.
• ✖️ No, I don’t have the time and I’m okay to wait for the community / maintainers to resolve this issue.

[jczacharia]

The fix for this is in #9031

If you want a quick fix for this just go into node_modules/typeorm/query-builder/SelectQueryBuilder.js and add his code from this: https://github.com/typeorm/typeorm/pull/9031/files#diff-52bea788267888fdbb5f795f0dfb61504f16bd43e0afdfa28848abb4435121b5

I'm doing my builds locally so it's no issue for me but I would consider this a critical bug so hopefully this PR can get shipped soon.

[pleerock]

duplicate of #8890

[tGeorgiy]

Many-To-Many find where Relation is Null still not working..