Raise base test coverage

[alexander-yevsyukov]

What

Raises line coverage of the :base module from 89.6% → ~96.5% by adding and extending Kotlin Spec tests.

Scope

This PR is primarily test coverage, but its diff against master also includes non-test build/release artifacts that were already committed on this branch before the test work:

• config — submodule pointer update.

No :base production (src/main) code is modified — the coverage was achieved purely by exercising existing public/internal API from tests.

What changed (tests)

New and extended JUnit 5 suites covering previously-untested paths:

• query — Columns (immutable-list delegation), Distribution (AND/OR distributive law), Columns/RecordColumn/SortBy/IdParameter/SubjectParameter value semantics, ComparisonOperator symbols, QueryPredicate emptiness/equality, EntityQueryBuilder custom-column criterion + transformer, IdCriterion vararg ids.
• code.proto — Linker (partial resolution, toString, validation-error wrapping), FileDescriptorSetReader, FileSet (parse/of/parseAsKnownFiles/union), TypeSet, FieldDeclaration, MessageType, PackageName/FieldName, SourceFile, DescriptorSetReferenceFile.create.
• type — KnownTypes (toString, readResolve), Json error paths, TypeUrl parsing, EnumType, ServiceType, MessageClass, PubPreconditions, UnknownTypeException.
• io / string / protobuf / base — Resource/ResourceObject/ResourceDirectory, Delete, Files2, Glob, StringifierRegistry, built-in stringifier singletons, Durations2, Field.nested, Errors (ErrorWithMessage branch).

Also normalizes @Nested test groups to the backticked-name layout, removing @DisplayName from @Nested inner classes per the kotlin-jvm-tester house convention (one pre-existing file, FieldDescriptorProtoExtsSpec, included).

Reviewer notes

• All new tests are Kotlin with Kotest assertions and Guava EqualsTester; stubs, not mocks; Spec/Test suffixes per convention.
• The remaining ~140 uncovered lines are non-actionable for JaCoCo/Kover: throw factory(...) lines (the post-athrow probe is unreachable), inline/reified functions (inlined at call sites), IOException catch blocks, and guarded/dead code (e.g. KnownTypes.extendWith behind InvocationGuard, Linker.addUnresolved).
• Pre-PR gate run locally: ./gradlew build PASS (incl. detekt), spine-code-review + kotlin-engineer APPROVE.

🤖 Generated with Claude Code
🙌 Edited by @alexander-yevsyukov

[Copilot]

Pull request overview

This pull request primarily increases test coverage in the :base module by adding new Kotlin/JUnit 5 + Kotest specs and extending existing tests to hit previously uncovered branches and value semantics. It also updates snapshot/versioning metadata and introduces buildSrc Kover/TestKit coverage wiring (not reviewed here per repo rules for buildSrc/**).

Changes:

• Added/extended :base module tests covering type, query, code.proto, io, protobuf, string, and base utilities.
• Bumped the published snapshot version from 2.0.0-SNAPSHOT.401 to 2.0.0-SNAPSHOT.402 and refreshed generated dependency documentation.
• Added buildSrc logic to collect/merge TestKit worker JaCoCo .exec data into Kover reports (skipped in review per buildSrc/** rule).

Reviewed changes

Copilot reviewed 34 out of 35 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
version.gradle.kts	Bumps snapshot version to .402.
docs/dependencies/pom.xml	Updates documented BOM version to .402.
docs/dependencies/dependencies.md	Refreshes generated dependency report for .402.
buildSrc/src/main/kotlin/io/spine/gradle/testing/TestKitCoverage.kt	Adds TestKit JaCoCo agent wiring (skipped: buildSrc/**).
buildSrc/src/main/kotlin/io/spine/gradle/report/coverage/KoverConfig.kt	Merges TestKit .exec into Kover totals (skipped: buildSrc/**).
base/src/test/kotlin/io/spine/type/TypeMiscSpec.kt	Adds coverage for EnumType.toProto().
base/src/test/kotlin/io/spine/type/TypeMembersSpec.kt	Adds/extends tests for TypeUrl, MessageType, ServiceType, and UnknownTypeException.
base/src/test/kotlin/io/spine/type/KnownTypesSpec.kt	Extends tests for KnownTypes.toString() and deserialization behavior.
base/src/test/kotlin/io/spine/type/JsonSpec.kt	Adds error-path tests for malformed JSON parsing and unknown-type JSON printing.
base/src/test/kotlin/io/spine/string/StringifierSingletonsSpec.kt	Verifies built-in stringifiers preserve singleton identity after deserialization.
base/src/test/kotlin/io/spine/string/StringifierRegistryMissingSpec.kt	Adds negative test for missing stringifier registration.
base/src/test/kotlin/io/spine/query/QueryValueObjectsSpec.kt	Adds value semantics and predicate/id criterion coverage for query value objects.
base/src/test/kotlin/io/spine/query/EntityQuerySpec.kt	Adds coverage for custom-column criterion and transformed query building.
base/src/test/kotlin/io/spine/query/DistributionSpec.kt	Adds distributive-law coverage for complex AND/OR expressions.
base/src/test/kotlin/io/spine/query/ComparisonOperatorSymbolsSpec.kt	Verifies ComparisonOperator.toString() symbols.
base/src/test/kotlin/io/spine/query/ColumnsSpec.kt	Adds delegation/immutability coverage for Columns.
base/src/test/kotlin/io/spine/protobuf/Durations2ConverterSpec.kt	Adds coverage for Durations2 conversion and converter naming.
base/src/test/kotlin/io/spine/io/ResourceTest.kt	Extends tests for Resource.read, locateAll error path, and equality semantics.
base/src/test/kotlin/io/spine/io/ResourceDirectorySpec.kt	Adds equality semantics coverage for ResourceDirectory.
base/src/test/kotlin/io/spine/io/IoMiscSpec.kt	Adds coverage for Files2.systemTempDir() and Glob.extensionLowerAndUpper().
base/src/test/kotlin/io/spine/io/DeleteSpec.kt	Adds coverage for recursive delete and shutdown-hook registration.
base/src/test/kotlin/io/spine/code/proto/SourceFileSpec.kt	Adds coverage for SourceFile wrapper behavior.
base/src/test/kotlin/io/spine/code/proto/PackageNameAndFieldNameSpec.kt	Adds coverage for PackageName and FieldName helpers.
base/src/test/kotlin/io/spine/code/proto/MessageTypeSpec.kt	Extends tests for proto conversion, signal detection, field lookup, UUID-value check.
base/src/test/kotlin/io/spine/code/proto/LinkerSpec.kt	Adds coverage for partial resolution, toString, and validation error wrapping.
base/src/test/kotlin/io/spine/code/proto/FileSetSpec.kt	Extends coverage for FileSet union/of/parse/parseAsKnownFiles and formatting.
base/src/test/kotlin/io/spine/code/proto/FileDescriptorSetReaderSpec.kt	Adds coverage for parse/tryParse for bytes and streams, including malformed input.
base/src/test/kotlin/io/spine/code/proto/FieldDescriptorProtoExtsSpec.kt	Normalizes nested test group naming to backticked layout.
base/src/test/kotlin/io/spine/code/proto/FieldDeclarationSpec.kt	Extends coverage for field numbers, type predicates, map helpers, entity ID detection.
base/src/test/kotlin/io/spine/code/proto/DescriptorSetReferenceFileSpec.kt	Extends coverage for creating desc.ref pointing at a descriptor set.
base/src/test/kotlin/io/spine/base/FieldNestingSpec.kt	Adds coverage for Field.nested(...) behavior.
base/src/test/kotlin/io/spine/base/ErrorsWithMessageSpec.kt	Adds coverage for Errors.fromThrowable ErrorWithMessage branch.
base/src/test/java/io/spine/type/MessageClassTest.java	Extends coverage for MessageClass.typeUrl() and equality behavior.
base/src/test/java/io/spine/code/proto/TypeSetTest.kt	Extends coverage for TypeSet bulk add, equality, and toString().

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.06%. Comparing base (5c5e777) to head (3257092).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #935      +/-   ##
==========================================
+ Coverage   87.15%   94.06%   +6.91%     
==========================================
  Files         193      193              
  Lines        4164     4164              
  Branches      339      339              
==========================================
+ Hits         3629     3917     +288     
+ Misses        412      147     -265     
+ Partials      123      100      -23     

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[alexander-yevsyukov]

Please see my comments.

[alexander-yevsyukov]

Please see my comments.

[Copilot]

Pull request overview

Copilot reviewed 35 out of 36 changed files in this pull request and generated no new comments.