[MAVEN PLUGIN; GRADLE-PLUGIN] - Add KDoc/Javadoc to the Gradle plugin and integrate Dokka so IDEs show helpful tooltips; fix missing parameter wiring; improve merged-spec handling to match the Maven plugin

[Picazsoo]

PR checklist

• Read the contribution guidelines.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

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  Commit all changed files.
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---

Summary by cubic

Adds KDoc/Javadoc to the Gradle plugin with Dokka-powered javadocJar for IDE tooltips, fixes missing parameter wiring, and aligns merged-spec handling with the Maven plugin, including accurate up-to-date checks.

• New Features

  • Integrated org.jetbrains.dokka-javadoc (2.2.0); javadocJar now builds from Dokka output and is published.
  • Added Gradle options: strictSpec, minimalUpdate, generateRecursiveDependentModels (no plugin defaults; config-file values win unless set), plus mergedFileInfoName, mergedFileInfoDescription, mergedFileInfoVersion (with defaults).
  • Expanded KDoc across Gradle properties and tasks; added Javadoc to Maven verbose and cleanupOutput.

• Bug Fixes

  • Wired enumNameMappings, operationIdNameMappings, and mergedFileName from the openApiGenerate extension to the task.
  • Passed auth and merged-spec info fields into the merged-spec builder; added a conditional input fingerprint to stabilize up-to-date checks when merging is enabled.
  • Ensured generateRecursiveDependentModels is honored via the global setting; added ParameterWiringRegressionTest (with an enum spec) to prevent regressions.

^{Written for commit c46500e. Summary will update on new commits.}

[cubic-dev-ai]

2 issues found across 10 files

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

2 issues found across 11 files

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

3 issues found across 11 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/extensions/OpenApiGeneratorGenerateExtension.kt">

<violation number="1" location="modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/extensions/OpenApiGeneratorGenerateExtension.kt:405">
P2: KDoc contradicts property semantics: `logToStderr` is documented as writing to STDOUT, but should be STDERR.</violation>
</file>

<file name="modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/tasks/GenerateTask.kt">

<violation number="1" location="modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/tasks/GenerateTask.kt:937">
P2: Merged-spec metadata fingerprint uses ambiguous `|` delimiter concatenation that can cause cache key collisions when user-provided values contain `|`.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: KDoc contradicts property semantics: logToStderr is documented as writing to STDOUT, but should be STDERR.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/extensions/OpenApiGeneratorGenerateExtension.kt, line 405:

<comment>KDoc contradicts property semantics: `logToStderr` is documented as writing to STDOUT, but should be STDERR.</comment>

<file context>
@@ -360,11 +397,12 @@ open class OpenApiGeneratorGenerateExtension(private val project: Project) {
 
     /**
-     * To write all log messages (not just errors) to STDOUT
+     * To write all log messages (not just errors) to STDOUT. Defaults to `false`.
      */
     val logToStderr = project.objects.property<Boolean>()
</file context>

Suggested change

	* To write all log messages (not just errors) to STDOUT. Defaults to `false`.
	+ * To write all log messages (not just errors) to STDERR. Defaults to `false`.

[cubic-dev-ai]

P2: Merged-spec metadata fingerprint uses ambiguous | delimiter concatenation that can cause cache key collisions when user-provided values contain |.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator-gradle-plugin/src/main/kotlin/org/openapitools/generator/gradle/plugin/tasks/GenerateTask.kt, line 937:

<comment>Merged-spec metadata fingerprint uses ambiguous `|` delimiter concatenation that can cause cache key collisions when user-provided values contain `|`.</comment>

<file context>
@@ -852,9 +873,80 @@ abstract class GenerateTask : DefaultTask() {
+        get() {
+            if (!inputSpecRootDirectory.isPresent) return null
+            if (inputSpecRootDirectorySkipMerge.getOrElse(false)) return null
+            return "${mergedFileInfoName.orNull}|${mergedFileInfoDescription.orNull}|${mergedFileInfoVersion.orNull}"
+        }
+
</file context>