fix(MergedSpecBuilder): merge path items by HTTP method instead of overwriting on path collision

[Picazsoo]

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---

Summary by cubic

Adds a mergeMode to improve multi-spec merging. Default REF preserves the original $ref-based index; opt-in DEEP merges paths by HTTP method and dedupes components with conflict handling.

• Bug Fixes

  • Merge path items by HTTP method on path collisions; on duplicate path+method keep last in REF, keep first (or fail) in DEEP.
  • Merge components by name; dedupe identical; warn on conflicts (or fail in DEEP).
  • Preserve x- vendor extensions and deduplicate server URLs; add http://localhost:8080 if none.

• New Features

  • Add mergeMode: REF (default, original behavior) or DEEP (inline merge with component dedupe/conflict detection). Exposed in CLI (--merge-mode), Gradle (mergeMode), and Maven (mergeMode).
  • Add mergeConflictStrategy: WARN (default) or FAIL for DEEP. Exposed in CLI (--merge-conflict-strategy), Gradle (mergeConflictStrategy), and Maven (mergeConflictStrategy).
  • Only process .yaml, .yml, .json; ignore invalid files; deterministic ordering; choose JSON output if the first spec is JSON.

^{Written for commit f5f50a0. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found and verified against the latest diff

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-maven-plugin/src/main/java/org/openapitools/codegen/plugin/ValidateMojo.java">

<violation number="1" location="modules/openapi-generator-maven-plugin/src/main/java/org/openapitools/codegen/plugin/ValidateMojo.java:272">
P2: mergeConflictStrategy is parsed and applied unconditionally despite being documented as DEEP-only. A null or invalid value will crash a REF-mode build with an unwrapped IllegalArgumentException/NullPointerException, bypassing the MojoExecutionException handling in execute().</violation>
</file>

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

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: mergeConflictStrategy is parsed and applied unconditionally despite being documented as DEEP-only. A null or invalid value will crash a REF-mode build with an unwrapped IllegalArgumentException/NullPointerException, bypassing the MojoExecutionException handling in execute().

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator-maven-plugin/src/main/java/org/openapitools/codegen/plugin/ValidateMojo.java, line 272:

<comment>mergeConflictStrategy is parsed and applied unconditionally despite being documented as DEEP-only. A null or invalid value will crash a REF-mode build with an unwrapped IllegalArgumentException/NullPointerException, bypassing the MojoExecutionException handling in execute().</comment>

<file context>
@@ -251,6 +268,8 @@ private Optional<String> mergeInDirectory() {
       mergedSpec = Optional.of(new MergedSpecBuilder(inputSpecRootDirectory, mergedFileName,
           mergedFileInfoName, mergedFileInfoDescription, mergedFileInfoVersion, auth)
+          .withMergeMode(MergedSpecBuilder.MergeMode.valueOf(mergeMode.toUpperCase(java.util.Locale.ROOT)))
+          .withConflictStrategy(MergedSpecBuilder.MergeConflictStrategy.valueOf(mergeConflictStrategy.toUpperCase(java.util.Locale.ROOT)))
           .buildMergedSpec());
       LOGGER.info("Merge input spec would be used - {}", mergedSpec.get());
</file context>