Fix culture-dependent date formatting tests to work with different system locales

[Krishanthaudayakumara]

Description / Motivation

Issue

Tests in the Sitecore ASP.NET Core SDK were failing when run on systems with non-US locales (e.g., Danish locale). The failures occurred because the tests were using hardcoded US date format expectations while the DateTagHelper implementation correctly uses CultureInfo.CurrentCulture when no specific culture is provided.

Root Cause

The test assertions were inconsistent with the actual implementation behavior:

• Implementation: Uses CultureInfo.CurrentCulture when no culture is specified (line 65 in DateTagHelper.cs)
• Tests: Expected hardcoded US format strings (e.g., "05/04/2012") regardless of system locale

This mismatch caused test failures when running on systems with different date formatting conventions (e.g., Danish locale uses "05-04-2012" format).

Solution

Updated test assertions to dynamically generate expected values using the current culture instead of hardcoded strings:

1. Unit Tests (DateTagHelperFixture.cs):

   • Modified custom format tests to explicitly specify culture and generate expected values accordingly
   • Added parameterized tests for multiple cultures (en-US, da-DK, uk-UA)

2. Integration Tests:

   • AllFieldTagHelpersFixture.cs: Use TestConstants.DateTimeValue.ToString("MM/dd/yyyy", CultureInfo.CurrentCulture)
   • DateFieldTagHelperFixture.cs: Generate expected format strings dynamically
   • RichTextFieldTagHelperFixture.cs: Use culture-aware date parsing and formatting
   • ViewFieldsBindingFixture.cs: Parse dates with invariant culture and format with current culture

Behavior

• Tests now pass consistently regardless of the system locale
• Implementation behavior remains unchanged (still correctly uses current culture)
• Test coverage is improved with explicit multi-culture testing

This fix ensures the test suite is portable across different regional settings while maintaining the correct functionality of culture-aware date formatting.

Fixes #34

Testing

• The Unit & Intergration tests are passing.
• I have added the necessary tests to cover my changes.

Terms

• I agree to follow this project's Code of Conduct.

[robearlam]

Added a couple of inline comments, also you've made code changes in the DateTagHelper.cs but I'm not seeing any changes to the Unit Tests for that class. If you've changed functionality then there should be a related unit test added to ensure it continues to function as expected.

[Copilot]

Pull Request Overview

This PR fixes culture-dependent date formatting tests that were failing on systems with non-US locales. The tests previously used hardcoded US date format expectations while the DateTagHelper implementation correctly uses the current system culture.

• Updated unit tests to use parameterized testing with multiple cultures (en-US, da-DK, uk-UA)
• Modified integration tests to dynamically generate expected date strings using current culture
• Added explicit culture specification in date formatting tests to ensure consistent behavior

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
DateTagHelperFixture.cs	Converted hardcoded date format tests to parameterized tests with explicit culture handling
AllFieldTagHelpersFixture.cs	Updated date field assertion to use current culture formatting
DateFieldTagHelperFixture.cs	Changed hardcoded date strings to dynamically generated culture-aware formats
RichTextFieldTagHelperFixture.cs	Added culture-aware date parsing and formatting for expected values
ViewFieldsBindingFixture.cs	Implemented invariant culture parsing with current culture formatting

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