refactor: pass parent schema to SchemaType constructors in interpretAsType to make implementing custom container types easier

[vkarpov15]

Summary

Implementing your own container type is a pain unless the container type happens to extend from Array, because otherwise you need to handle interpreting of by yourself. For example, imagine { type: Set, of: { type: String, required: true } } - right now anyone implementing a set schematype would have to re-implement interpretAsType semantics themselves. We had to do a bit of a hack to avoid having to re-implement interpretAsType for unions, but with this fix we can remove the hack as well.

Examples

[Copilot]

Pull Request Overview

This refactor improves the extensibility of custom container types in Mongoose by passing the parent schema as a parameter to SchemaType constructors. Previously, implementing custom container types that needed to interpret nested schemas (like { type: Set, of: { type: String } }) required re-implementing interpretAsType logic or using workarounds like the options.parentSchema hack used in the Union type.

Key changes:

• Added parentSchema parameter to all SchemaType constructors via interpretAsType
• Removed the Union-specific hack that attached parent schema to options
• Union type now receives parent schema directly as a constructor parameter

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
lib/schema.js	Updated interpretAsType to pass this (parent schema) as fourth parameter to SchemaType constructors, removing Union-specific workaround
lib/schema/union.js	Modified Union constructor to accept parentSchema parameter instead of accessing it from options

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[hasezoey]

LGTM, though it seems Github CI's Node 22 does not like some change here, though any other version just works.

The CI errors in question

Runner: Node 22 MongoDB 6.0.15 OS ubuntu-22.04
Full Node Version in runner: 22.21.0

  1) Double
       cast errors
         when a non-numeric string is provided to an Double field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Double failed for value "helloworld" (type string) at path "myDouble" because of "SyntaxError"' == 'Cast to Double failed for value "helloworld" (type string) at path "myDouble"'
      + expected - actual
      -Cast to Double failed for value "helloworld" (type string) at path "myDouble" because of "SyntaxError"
      +Cast to Double failed for value "helloworld" (type string) at path "myDouble"
      
      at Context.<anonymous> (test/double.test.js:284:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  2) Int32
       cast errors
         when a non-integer decimal input is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "-42.4" (type number) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "-42.4" (type number) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "-42.4" (type number) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "-42.4" (type number) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:304:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  3) Int32
       cast errors
         when a non-numeric string is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "helloworld" (type string) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "helloworld" (type string) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "helloworld" (type string) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "helloworld" (type string) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:322:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  4) Int32
       cast errors
         when a non-integer decimal string is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "1.2" (type string) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "1.2" (type string) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "1.2" (type string) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "1.2" (type string) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:340:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  5) Int32
       cast errors
         when NaN is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "NaN" (type number) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "NaN" (type number) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "NaN" (type number) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "NaN" (type number) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:358:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  6) Int32
       cast errors
         when value above INT32_MAX is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "2147483648" (type number) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "2147483648" (type number) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "2147483648" (type number) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "2147483648" (type number) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:376:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  7) Int32
       cast errors
         when value below INT32_MIN is provided to an Int32 field
           throws a CastError upon validation:
      AssertionError [ERR_ASSERTION]: 'Cast to Int32 failed for value "-2147483649" (type number) at path "myInt" because of "SyntaxError"' == 'Cast to Int32 failed for value "-2147483649" (type number) at path "myInt"'
      + expected - actual
      -Cast to Int32 failed for value "-2147483649" (type number) at path "myInt" because of "SyntaxError"
      +Cast to Int32 failed for value "-2147483649" (type number) at path "myInt"
      
      at Context.<anonymous> (test/int32.test.js:394:16)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  8) model: findOneAndUpdate:
       bug fixes
         single nested doc cast errors (gh-3602):
      AssertionError [ERR_ASSERTION]: 'Cast to Number failed for value "not a num" (type string) at path "street" because of "SyntaxError"' == 'Cast to Number failed for value "not a num" (type string) at path "street"'
      + expected - actual
      -Cast to Number failed for value "not a num" (type string) at path "street" because of "SyntaxError"
      +Cast to Number failed for value "not a num" (type string) at path "street"
      
      at Context.<anonymous> (test/model.findOneAndUpdate.test.js:1357:14)
      at process.processTicksAndRejections (node:internal/process/task_queues:105:5)

  9) validation docs
       Cast Errors:
      AssertionError [ERR_ASSERTION]: 'Cast to Number failed for value "not a number" (type string) at path "numWheels" because of "SyntaxError"' == 'Cast to Number failed for value "not a number" (type string) at path "numWheels"'
      + expected - actual
      -Cast to Number failed for value "not a number" (type string) at path "numWheels" because of "SyntaxError"
      +Cast to Number failed for value "not a number" (type string) at path "numWheels"
      
      at Context.<anonymous> (test/docs/validation.test.js:384:12)
      at process.processImmediate (node:internal/timers:485:21)

[hasezoey]

This change should likely be documented somehwere in the code, though i dont know if this already exists somehwere (and SchemaType itself seems to have different parameters, so likely not there).
Also the "Custom Schema Types" guide seems to be somewhat outdated, and this change should likely be documented there as a available parameter (/docs/customschematypes.md).