New expression: displayValue

[bjosttveit]

Description

Adds a new expression function: ["displayValue", "<componentId>"], which returns the formatted string representation of the component's form data which can be used to build texts. To make this work I had to convert all of the hooks used into get-functions with the required state as arguments. The hooks are preserved but use the get-functions under the hood to avoid duplicate implementations (similar to useLanguage)

Shared tests:

• Hidden component
• Null
• Missing component
• Component without display value
• Input component
• Input component with number format
• Address component
• Datepicker component
• Custom component
• List component
• Map component
• Textarea component
• Checkboxes component
• Radiobuttons component
• Multiple select component
• Dropdown component
• FileUpload component
• FileUploadWithTag component
• Likert component

Related Issue(s)

• closes Add displayValue function to Expressions. #1208
• As an app developer I want to show the display value as a variable in text #1105

Verification/QA

• Manual functionality testing
  • I have tested these changes manually
  • Creator of the original issue (or service owner) has been contacted for manual testing (or will be contacted when released in alpha)
  • No testing done/necessary
• Automated tests
  • Unit test(s) have been added/updated
  • Cypress E2E test(s) have been added/updated
  • No automatic tests are needed here (no functional changes/additions)
  • I want someone to help me make some tests
• UU/WCAG (follow these guidelines until we have our own)
  • I have tested with a screen reader/keyboard navigation/automated wcag validator
  • No testing done/necessary (no DOM/visual changes)
  • I want someone to help me perform accessibility testing
• User documentation @ altinn-studio-docs
  • Has been added/updated
  • No functionality has been changed/added, so no documentation is needed
  • I will do that later/have created an issue
• Changes/additions to component properties
  • Changes are reflected in both src/layout/layout.d.ts and layout.schema.v1.json, and these are all backwards-compatible
  • No changes made
• Support in Altinn Studio
  • Issue(s) created for support in Studio
  • This change/feature does not require any changes to Altinn Studio
• Sprint board
  • The original issue (or this PR itself) has been added to the Team Apps project and to the current sprint board
  • I don't have permissions to do that, please help me out
• Labels
  • I have added a kind/* label to this PR for proper release notes grouping
  • I don't have permissions to add labels, please help me out

[olemartinorg]

Great work! 👏 Maybe we should add a unit-test to make sure every (new) component implementing getDisplayValue() has a corresponding shared test for this expression function? 🤔 That way we would ensure the backend gets a push to implement new components for this functionality as well.

[bjosttveit]

Great work! 👏 Maybe we should add a unit-test to make sure every (new) component implementing getDisplayValue() has a corresponding shared test for this expression function? 🤔 That way we would ensure the backend gets a push to implement new components for this functionality as well.

Great idea!

[sonarcloud]

SonarCloud Quality Gate failed.   

11 Bugs
0 Vulnerabilities
0 Security Hotspots
7 Code Smells

83.5% Coverage
1.7% Duplication

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