Support objects in expressions

[TomasEng]

Important

This pull request is stacked upon #1769, which should be merged first.

Description

This pull request adds support for objects in expressions, along with an object function for creating an object. Here is an overview of the changes:

• New object function in ExpressionEvaluator. Because of the complexity of the function, I created a separate class named ObjectFunctionEvaluator for evaluating the function.
• Support for dictionaries in ExpressionValue. Most of the code did already exist, hiding in comments.

Here is the corresponding change in App frontend: Altinn/altinn-studio#18982

Related Issue(s)

• Support objects in expressions app-frontend-react#4190

Verification

• Your code builds clean without any errors or warnings
• Manual testing not possible since there is no use case for this until we add functions that accept objects as parameters; the automated unit tests should be sufficient
• Relevant automated test added (if you find this hard, leave it and we'll help out)
• All tests run green

Documentation

• User documentation is updated with a separate linked PR in altinn-studio-docs.: Add docs about lists and objects in expressions altinn-studio-docs#2894

Summary by CodeRabbit

• New Features
  • Added @object expression function to create objects from alternating key/value arguments.
  • Extended the expression value system to support JSON object values end-to-end (creation, access, and string rendering).
  • Improved JSON (de)serialization to handle object values consistently, including during equality formatting.
• Tests
  • Added and expanded shared expression fixtures and test coverage for object construction and object/list lookup scenarios.
  • Updated evaluator tests to cover additional JSON object/array combinations and adjusted “nonsense” equality inputs.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 4df921c7-e753-424a-ab62-46f20668296f

📥 Commits

Reviewing files that changed from the base of the PR and between aa24c44 and 84e2800.

📒 Files selected for processing (1)

• test/Altinn.App.Core.Tests/PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt

---

📝 Walkthrough

Walkthrough

Adds the @object expression function to the layout expression evaluator. ExpressionValue is extended to hold JsonObject as a first-class variant with a new constructor, implicit conversion, accessor, and serialization paths. A new ObjectFunctionEvaluator implements the key/value pair construction logic. ExpressionEvaluator dispatches the new ExpressionFunction.@object enum member to this evaluator.

Changes

@object expression function

Layer / File(s)	Summary
ExpressionFunction enum and ExpressionValue JsonObject variant src/Altinn.App.Core/Models/Expressions/ExpressionFunction.cs, src/Altinn.App.Core/Internal/Expressions/ExpressionValue.cs	Declares the @object enum member and extends ExpressionValue with a JsonObject backing field, constructor, implicit conversion operator, Object accessor property, updated FromObject/ToObject factories, ToString/ToStringForText serialization, and ExpressionTypeUnionConverter read/write support for object tokens.
ObjectFunctionEvaluator and dispatch wiring src/Altinn.App.Core/Internal/Expressions/ObjectFunctionEvaluator.cs, src/Altinn.App.Core/Internal/Expressions/ExpressionEvaluator.cs	ObjectFunctionEvaluator.Evaluate validates even argument count, extracts string keys, serializes values to JsonNode, enforces key uniqueness, and returns a JsonObject. ExpressionEvaluator adds a dispatch case for ExpressionFunction.@object that delegates to a new Object(args) helper.
Tests, fixtures, and public API snapshot test/.../CommonTests/TestFunctions.cs, test/.../shared-tests/functions/object/object.json, test/.../shared-tests/functions/dataModel/lookup-object.json, test/.../shared-tests/functions/dataModel/lookup-list.json, test/.../shared-tests/functions/component/lookup-list.json, test/.../shared-tests/functions/list/list.json, test/.../ExpressionEvaluatorTests/ExpressionValueTests.cs, test/.../ExpressionEvaluatorTests/EqualsTests.cs, test/.../PublicApiTests.PublicApi_ShouldNotChange_Unintentionally.verified.txt	Adds Object_Theory xUnit method, object.json shared test cases (success and error cases), new and updated data model/component fixtures for object lookup and list nesting, updates ExpressionValueTests and EqualsTests for the new Object property, and updates the public API snapshot.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• Altinn/app-lib-dotnet#1769: Adds the list function to ExpressionEvaluator, ExpressionValue, and ExpressionFunction using the same pattern this PR follows for @object.

Suggested reviewers

• martinothamar
• ivarne

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 30.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The pull request title clearly and concisely summarizes the main change: introducing support for objects in expressions, which is the primary objective of this changeset.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch support-objects-in-expressions

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[TomasEng]

@coderabbitai review

[coderabbitai]

✅ Actions performed

Review triggered.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[ivarne]

Ikke noe stort å bemerke her heller 👍

[olavsorl]

LGTM ✅

[sonarqubecloud]

Quality Gate passed

Issues
11 New issues
0 Accepted issues

Measures
0 Security Hotspots
89.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud