JUnit Jupiter best practices

[slachiewicz]

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[Copilot]

Pull Request Overview

This pull request modernizes JUnit test code across multiple test classes by adopting Java 8+ language features and JUnit 5 conventions. The changes improve code readability and maintainability while standardizing test naming patterns.

• Updated test class and method visibility from public to package-private (removing public modifier)
• Renamed test methods to remove "test" prefix following JUnit 5 naming conventions
• Simplified exception declarations from specific exceptions to generic Exception
• Modernized Java syntax using diamond operators for generic type inference
• Converted anonymous classes to lambda expressions where applicable
• Removed unnecessary wrapper calls (e.g., Collections.unmodifiableList(Collections.singletonList(...)) to Collections.singletonList(...))
• Cleaned up unused imports
• Made fields final where appropriate

Reviewed Changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
StringUtilsTest.java	Updated class/method visibility and naming
FieldBasedObjectInterpolatorTest.java	Modernized syntax with diamond operators, removed redundant Collections wrapper, updated visibility/naming
MultiDelimiterStringSearchInterpolatorTest.java	Simplified exceptions, added diamond operators, lambda conversions, removed unused imports, updated naming
MultiDelimiterInterpolatorFilterReaderTest.java	Comprehensive modernization including lambdas, diamond operators, updated visibility/naming
FixedStringSearchInterpolatorTest.java	Lambda conversions, diamond operators, simplified exceptions, made field final, updated naming
EnvarBasedValueSourceTest.java	Lambda conversions, diamond operators, removed license header, updated naming
StringSearchInterpolatorTest.java	Extensive modernization including lambdas, diamond operators, made field final, removed license header
RegexBasedInterpolatorTest.java	Lambda conversions, diamond operators, removed license header, updated naming
PropertiesBasedValueSourceTest.java	Updated visibility and naming
PrefixedValueSourceWrapperTest.java	Updated visibility and naming
PrefixedObjectValueSourceTest.java	Updated visibility, naming, and diamond operators
PrefixAwareRecursionInterceptorTest.java	Updated visibility, naming, and removed unnecessary array wrapper
InterpolatorFilterReaderTest.java	Updated visibility, naming, and diamond operators
FeedbackingValueSourceTest.java	Updated visibility, naming, and simplified exceptions

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[Copilot]

Missing diamond operator '<>' for HashMap instantiation. Should be 'new HashMap<>()' to be consistent with other modernizations in this PR.

Suggested change

	Map<String, String> context = new HashMap();
	Map<String, String> context = new HashMap<>();