def "matches id (#projectPath1,#libraryName1, #variant1) with (#projectPath2,#libraryName2, #variant2)"() {
        expect:
        LibraryComponentSelector defaultBuildComponentSelector = new DefaultLibraryComponentSelector(projectPath1, libraryName1, variant1)
        LibraryBinaryIdentifier defaultBuildComponentIdentifier = new DefaultLibraryBinaryIdentifier(projectPath2, libraryName2, variant2)

  rankdir=LR

  compileVariantSwift -> linkVariant -> installVariant -> assembleVariant [dir=back, style=dashed]
  compileVariantSwift[label=<compile<i>Variant</i>Swift>]
  linkVariant[label=<link<i>Variant</i>>]
  installVariant[label=<install<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

            Collections.emptyList()
        );

        // It is fine if no graph variants satisfy our request.
        // Variant reselection allows no target variants to be found.
        if (graphVariant == null) {
            return ImmutableSet.of();
        }

        // Next, return all artifact variants for the selected graph variant.
        return getArtifactsForGraphVariant(graphVariant);
    }

    /**

xctest-variant-task-graph.png...

        ImmutableCapabilities capabilities = variantMetadataRules.applyCapabilitiesRules(variant, variant.getCapabilities());
        ImmutableList<? extends ComponentVariant.File> files = variantMetadataRules.applyVariantFilesMetadataRulesToFiles(variant, variant.getFiles(), id);
        boolean force = PlatformSupport.hasForcedDependencies(variant);

        if (variants == null || variants.isEmpty() || !allArtifactSet.isEmpty()) {
            visitor.visitOwnVariant(displayName, attributes.asImmutable(), allArtifactSet);
        }
        if (variants != null) {
            for (ConfigurationVariantInternal variant : variants.withType(ConfigurationVariantInternal.class)) {

  rankdir=LR

  compileVariantSwift -> {linkVariant, createVariant} -> assembleVariant [dir=back, style=dashed]
  compileVariantSwift[label=<compile<i>Variant</i>Swift>]
  linkVariant[label=<link<i>Variant</i>>]
  createVariant[label=<create<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

  // Adds linkage text between link* and create*
  linkVariant -> linkageText -> createVariant [style=invis]

  rankdir=LR

  compileVariantCpp -> {linkVariant, createVariant} -> assembleVariant [dir=back, style=dashed]
  compileVariantCpp[label=<compile<i>Variant</i>Cpp>]
  linkVariant[label=<link<i>Variant</i>>]
  createVariant[label=<create<i>Variant</i>>]
  assembleVariant[label=<assemble<i>Variant</i>>]

  // Adds linkage text between link* and create*
  linkVariant -> linkageText -> createVariant [style=invis]

        def variantDef = publications.variants.create("child")
        variantDef.attributes.attribute(Attribute.of("thing", String), "value")
        variantDef.artifacts.add(artifact)

        expect:
        def variants = getOutgoingVariants(publications)
        variants.size() == 1

        def child = variants.first()
        child.displayName.displayName == '<config> variant child'

Secondary variants are variants created via the Configuration#getOutgoing(): ConfigurationPublications API which also participate in selection, in addition to the configuration itself.

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