Bug: Mismatch in Studio and Engine handling of unresolved class mapping ID

[akphi]

Similar issues

• I have searched and found no existing similar issues

How are you using Studio?

Legend Studio

Current and expected behavior

A number of Pure users have mappings which contain class mapping IDs pointing at another mapping's class mappings. In Pure/Engine, we let this pass compilation phase. In Studio, we disallow this. This makes it hard for users to migrate to Studio. We should think of a strategy to make things loadable in Studio, but disallow users to make changes if they have this kind of error in their graph.

Steps to reproduce

Use the following grammar. Try compilation in text mode, Engine will pass while Studio graph builder will scream.

Model data

###Relational
Database model::Test
(
  Table FirmTable
  (
    id INTEGER PRIMARY KEY,
    Legal_name VARCHAR(200)
  )
  Table PersonTable
  (
    id INTEGER PRIMARY KEY,
    firm_id INTEGER,
    firstName VARCHAR(200),
    lastName VARCHAR(200)
  )

  Join FirmPerson(PersonTable.firm_id = FirmTable.id)
)


###Pure
Profile model::MyExtension
{
  stereotypes: [important];
  tags: [doc];
}

Enum model::IncType
{
  Corp,
  LLC
}

Class model::LegalEntity
{
  legalName: String[1];
}

Class model::Person
{
  firstName: String[1];
  lastName: String[1];
}

Class <<model::MyExtension.important>> {model::MyExtension.doc = 'This is a model of a firm'} model::Firm extends model::LegalEntity
[
  validName: $this.legalName->startsWith('')
]
{
  employees: model::Person[1..*];
  incType: model::IncType[1];
  employeeSize() {$this.employees->count()}: Number[1];
}


###Mapping
Mapping model::NewMapping
(
  *model::Firm: Relational
  {
    ~primaryKey
    (
      [model::Test]FirmTable.id
    )
    ~mainTable [model::Test]FirmTable
    legalName: concat([model::Test]FirmTable.Legal_name, '_LTD'),
    employees[idNotFound]: [model::Test]@FirmPerson
  }
  *model::Person: Relational
  {
    ~primaryKey
    (
      [model::Test]PersonTable.id
    )
    ~mainTable [model::Test]PersonTable
    firstName: [model::Test]PersonTable.firstName,
    lastName: [model::Test]PersonTable.lastName
  }
)

Environment

System:
    OS: macOS 11.6.4
  Binaries:
    Node: 16.8.0 - /private/var/folders/95/y32364512q77c1dvhkpnr_n80000gn/T/xfs-e9ca549e/node
    Yarn: 3.2.0 - /private/var/folders/95/y32364512q77c1dvhkpnr_n80000gn/T/xfs-e9ca549e/yarn
    npm: 7.21.0 - ~/.nvm/versions/node/v16.8.0/bin/npm
  Browsers:
    Chrome: 98.0.4758.102
    Firefox: 96.0.3

Possible solution and workaround

Discussed with @pierredebelen and @MauricioUyaguari. We will not hard-fail in Studio, the general strategy is detailed in #941

Contribution

• I would like to work on the fix for this issue

[akphi]

Moved to milestone 5.0.0 because this work needs engine change from @pierredebelen