feat(firestore, web): Web implementation for Pipeline APIs

[SelaseKay]

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[Lyokone]

case 'trim':
  return (_expr(argsMap, _kExpression) as interop.ExpressionJsImpl)
      .toLower();  // BUG: should be .trim()

Copy-paste bug. This will silently produce wrong results — a trim() call will lowercase the string instead of trimming whitespace.

[Lyokone]

We need to add a TODO or something? is it normal to inject it this way? Will it be supported in the normal bundle?

[SelaseKay]

https://www.gstatic.com/firebasejs/$version/firebase-firestore-pipelines.js bundle has support for both standard queries and Pipeline Operations. The previous bundle had support for only standard queries.

[Lyokone]

Are we missing those?

• negate
• as_boolean
• to_string_with_format
• bit_and, bit_or, bit_xor, bit_not, bit_left_shift, bit_right_shift
• document_id_from_ref
• array_reverse
• array_slice
• distance
• timestamp_diff
• map_from_pairs

[SelaseKay]

Besides array_reverse, document_id_from_ref, and as_boolean the others are not supported on Web

[Lyokone]

default:
  // Ignore unknown stages
  return pipeline;

If a stage type is unrecognized, it's silently skipped. This could produce subtly wrong query results that are extremely hard to debug. This should throw an error instead, like:

default:
  throw FirebaseException(
    plugin: 'cloud_firestore',
    message: 'Unknown pipeline stage: ${stage['stage']}',
  );

[Lyokone]

If dartify(d) returns null even when d is non-null (e.g. a JS object that can't be converted), the as Map<Object?, Object?> cast will throw. The version in firestore.dart handles this more safely:

final parsed = dartify(d);
return parsed != null ? Map<String, dynamic>.from(parsed as Map<Object?, Object?>) : null;