[BUG] CQN predicates expect wrong types

[siarhei-murkou]

Is there an existing issue for this?

• I have searched the existing issues

Current Behavior

Example:

import cqn from "@cap-js/cds-types";

const condition_1: cqn.predicate = [{ ref: ["prop_1"] }, "is", null];
const condition_2: cqn.predicate = [{ ref: ["prop_2"] }, "in", { val: ["val_1", "val_2"] }];

It leads to:

TS2322: Type { ref: string[]; } is not assignable to type
    Partial<string & ref & val & xpr & function_call & SELECT>
        Types of property valueOf are incompatible.
            Type () => Object is not assignable to type (() => string) & (() => Object)
                Type () => Object is not assignable to type () => string
                    Type Object is not assignable to type string

Expected Behavior

No TypeScript issues.

References

No references.

Versions

@cap-js/cds-typer: 0.15.0
@cap-js/sqlite: 1.2.1
@sap/cds: 7.5.3
@sap/cds-compiler: 4.0.2
@sap/cds-dk: 7.5.1
@sap/cds-dk (global): 7.3.1
@sap/cds-fiori: 1.1.0
@sap/cds-foss: 4.0.2
@sap/cds-mtxs: 1.14.2
@sap/eslint-plugin-cds: 2.6.4
Node.js: v18.18.2

Anything else? Logs?

As I got, the issue is due to this line:

export type predicate = UnionsToIntersections<_xpr>

Which is incorrect, because this intersection allows only string-like values. I suppose the value should be _xpr as it was defined in past.