Migrate from net.sourceforge.htmlunit to org.htmlunit

[akshayrai10]

Summary

• Upgrades HtmlUnit from the abandoned net.sourceforge.htmlunit coordinates to the actively maintained org.htmlunit:htmlunit:3.9.0, resolving two critical CVEs
• Updates the Selenium HtmlUnit Driver in jwebunit-webdriver-plugin from selenium-htmlunit-driver:2.52.0 to htmlunit3-driver:4.13.0, which is the only Selenium 4 driver that correctly depends on org.htmlunit:htmlunit:3.x and fully removes net.sourceforge.htmlunit from the classpath
• Fixes all API breaking changes introduced in HtmlUnit 3.x

Key API Breaking Changes Addressed

• Package rename: all com.gargoylesoftware.htmlunit.* → org.htmlunit.*
• DefaultCredentialsProvider.addCredentials(): password changed from String to char[]; addNTLMCredentials() removed, replaced with generic addCredentials() (NTLM negotiation is handled internally by HtmlUnit)
• HC5 shading: HtmlUnit 3.x bundles Apache HttpClient 5 internally, HC5 types are not importable by downstream consumers. Cookie.toHttpClient() replaced with direct org.htmlunit.util.Cookie API calls
• HtmlElement.asText() renamed to asNormalizedText()
• HtmlInput value semantics: in HtmlUnit 3.x, setValueAttribute() mutates the HTML attribute (the form-reset default) rather than the live DOM value. Replaced with setValue() at all call sites that intend to set user-visible field values; getValueAttribute() → getValue() for reading live DOM values
• CapabilityType.SUPPORTS_JAVASCRIPT: removed in Selenium 4 with no named constant replacement (W3C WebDriver spec does not include javascriptEnabled). Replaced with string literal "javascriptEnabled"
• XPath engine: HtmlUnit 3.x uses a strict XPath 1.0 evaluator (Apache Xalan). lower-case() (XPath 2.0) replaced with translate() equivalent in WebTester.java

To de‑risk the HtmlUnit 2.x → 3.x upgrade and Selenium driver changes, a dedicated suite of migration‑specific tests was added under jwebunit-htmlunit-plugin. These tests explicitly cover each behaviour change introduced by the new stack

• HtmlUnitCookieMappingTest - Verifies the rewritten getCookies() implementation after dropping Cookie.toHttpClient() (HC4) in favour of direct org.htmlunit.util.Cookie access.
• HtmlUnitValueSemanticsTest - Guards the new value semantics after switching from setValueAttribute() / getValueAttribute() to setValue() / getValue() on HtmlInput and in HtmlUnitElementImpl:
• HtmlUnitCheckboxCaseInsensitiveTest - Validates the XPath fix from the unsupported XPath 2.0 lower-case() function to the XPath 1.0 translate() equivalent in WebTester:
• HtmlUnitTestingEngineImplTest additions - Extends existing tests to cover new migration‑critical behaviour:

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