# Eve Parity Testing Harness The parity harness is the shared evidence path for Eve runtimes. It does not try to prove byte-identical pixels. It proves that every runtime is aiming at the same provider-owned CultUI surface: same fixture, same retained tree, same style-token expectations, same control anatomy, and explicit capture gaps. ## Authority - `tools/parity/parity-manifest.json` owns the fixture matrix, runtime list, and expectations. - `tools/parity/run-parity.mjs` owns semantic fixture checks and report generation. - Runtime capture adapters own screenshots or frame capture for their platform. - `artifacts/parity/latest.md` and `artifacts/parity/latest.json` are reports, not source truth. The manifest is the cut line. If a fixture or runtime is not in the manifest, it is not part of the parity claim. Runtime capability manifests are the runtime-owned side of that claim. When a runtime entry has `capabilityManifest`, the harness validates the JSON document against `gamecult.eve.runtime_capability.v1` and cross-checks runtime id, supported features, supported and unsupported plugin declarations, command transport schema, and incubation metadata. The central parity manifest may coordinate split-readiness, but the runtime body must publish the capability claim it expects other repos to consume. The web reference and Unity UI Toolkit both publish runtime capability manifests. Web uses `web/eve-runtime-capability.json` to make the browser oracle explicit: it consumes provider advertisements, lowers provider-owned surfaces, emits `gamecult.eve.command.v1` intents, and records Chrome headless capture evidence without becoming provider truth. Unity UI Toolkit uses the same path for its `sai.vn`, `norn.graph`, and `tex.math` plugin projection adapter proofs while leaving Sai, Norn, and TeX semantic authority in their independent sidecar plugin owners. ## Run Semantic checks: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-parity-harness.ps1 ``` Hard screenshot smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-parity-smoke.ps1 ``` Nightwing owns the Linux Flutter capture body. If its user-local Flutter SDK is missing, install it first: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\install-nightwing-flutter-sdk.ps1 ``` The smoke expands every resizable renderer across the manifest's responsive viewport matrix: - `phone`: 390 x 844 - `tablet`: 768 x 1024 - `desktop`: 1280 x 720 Device runtimes also capture native physical panel cases when the platform adapter can control orientation without overriding size. Android Flutter currently emits: - `native-portrait`: Periwinkle at physical portrait resolution - `native-landscape`: Periwinkle at physical landscape resolution The semantic runner writes: - `artifacts/parity/latest.md` - `artifacts/parity/latest.json` - `artifacts/parity//parity-report.md` - `artifacts/parity//parity-report.json` - `artifacts/conformance/latest/index.md` - `artifacts/conformance/latest/index.json` - `artifacts/conformance/latest/packs/*.json` - `artifacts/conformance//...` The conformance export includes `conformanceHandoffPath`, pointing at the machine-readable EveConformance split map. That handoff is incubation evidence: it names which runner, schema, consumer-smoke, and fixture-corpus paths move when the conformance body leaves Eve. Handoff documents are also copied into the export under `handoffs/*.json`. Consumer smokes assert those exported copies, not just Eve-local source paths, so owner repos can inspect plugin, provider, runtime, and conformance handoff maps from the exported pack itself. The conformance export also carries a `gamecult.eve.capability_matrix.v1` projection. It summarizes pack health, plugin ABI/capability claims, provider surfaces/commands/receipts, runtime feature/capture/command coverage, split readiness, and handoff counts. This is derived evidence for consumers, not a new source of truth. The export schema and consumer smoke now require minimum record shapes for plugins, providers, runtimes, and split targets. Owner repos should be able to depend on ids, owners, statuses, split targets, manifest or advertisement paths, feature/plugin arrays, and blocker/proof arrays without reading Eve's parity manifest. Capability gaps are exported as `capabilityGaps[]`. They are derived from missing plugin/provider/runtime evidence, declared unsupported plugin projection, capture gaps, and split blockers. Consumer smokes can assert named gap substrings with `--expect-capability-gap`. When a provider advertises a world-surface lowering target that no runtime claims, the gap is assigned to the matching pending runtime owner when one exists, such as `unity-scene` -> EveUnity or `tui` -> EveTui. Eve only owns the gap when no runtime target has been declared at all. The same facts are also exported as `worldSurfaceLoweringGaps[]` so runtime owners can consume provider id, surface id, target id, owner repo, runtime id, split target, and runtime status as typed fields instead of parsing the generic gap text. The full advertised-target ledger is exported as `worldSurfaceLoweringCoverage[]`. Each record joins a provider-owned world surface to one advertised lowering target and reports whether that target is `claimed`, `missing-claim`, or `missing-runtime`, along with the runtime owner and runtime id. Consumer smokes can assert complete coverage facts with `--expect-world-lowering-coverage `. Provider-owned world/editor surfaces are exported as `interactiveWorldSurfaces[]`. These records index the provider id, owner repo, surface id, surface kind, projection kind, state schemas, command boundary, receipt schema, lowering targets, and ownership rule so runtime lowerers can discover provider-authored world surfaces without importing provider source layout. Consumer smokes can assert advertised targets with `--expect-interactive-world-surface `. The command path for those targets is exported as `commandBoundaryCoverage[]`. Each record joins a provider-owned surface, advertised lowering target, runtime owner, provider command boundary, receipt schema, and runtime command envelope schema. Status is `covered` only when the runtime has claimed the target and advertises `gamecult.eve.command.v1`; otherwise it reports `missing-runtime`, `missing-runtime-claim`, `missing-provider-boundary`, or `missing-command-transport`. Consumer smokes can assert it with `--expect-command-boundary-coverage `. The browser reference lowerer also copies the active surface's advertised `worldInteraction.commandBoundary` and `worldInteraction.receiptSchema` into `gamecult.eve.command.v1` intents, falling back to component action metadata only when the advertisement lacks those fields. That keeps command routing on the provider/plugin advertisement contract instead of letting the browser reference probe provider source layout. Declared runtime/plugin projection gaps are exported as `runtimePluginProjectionGaps[]`. These records carry runtime id, runtime owner, split target, plugin id, reason, severity, and fixture lists so EveUnity, EveElectron, Sai, Norn, and TeX owners can distinguish "this projection runtime cannot project the plugin yet" from "plugin semantics belong in Eve core." Device-edge dashboard proofs that do not claim plugin projection are not listed as failed plugin clients. Consumer smokes can assert real projection gaps with `--expect-runtime-plugin-gap `. The same claims are exported as `runtimePluginProjectionCoverage[]`, including positive `supported` projection adapters and declared `unsupported` gaps. This lets runtime and plugin owners consume one ledger for "Unity UI Toolkit has projection adapters for independent Sai and Norn sidecar-advertised output," "Unity scene can project Norn's sidecar-advertised embedded graph shell," and "Electron does not have generic plugin projection yet" instead of walking nested runtime records. Consumer smokes can assert entries with `--expect-runtime-plugin-projection `. Provider surface plugin requirements are also joined with runtime projection support as `providerRuntimePluginProjectionCoverage[]`. These records answer the real lowering question: whether a provider surface's required or optional-nested plugin can be projected by a concrete runtime. Required plugin failures are blockers; optional nested failures are degraded lowerings. Consumer smokes can assert them with `--expect-provider-runtime-plugin-projection `. The conformance export includes runtime `capabilityManifestPath` and `capabilityManifestErrors` fields so external consumers can distinguish a generic projection runtime from a runtime that can project plugin-declared capabilities. Plugin handoff paths are exported as `plugins[].handoffPath` for owner repos such as Sai and Norn. These paths are incubation evidence for where plugin manifest, advertisement, ABI fixture, and conformance ownership must move; they are not plugin runtime state. Plugin ABI fixture operations are exported as `plugins[].abiOperationContracts` with `operation`, `input`, and `expect` blocks. Plugin owners can consume the operation-level contract for `describe`, `validate`, `project`, `lower`, `measure`, and `apply` without opening Eve-local fixture files. The same operation set is indexed as root `pluginAbiOperationCoverage[]` records with plugin id, owner repo, operation, status, fixture path, input keys, and expect keys. Plugin-owner smokes can assert contracted operations with `--expect-plugin-abi-operation-coverage ` without walking nested plugin records. Provider-advertised plugin requirements are indexed as root `providerPluginRequirementCoverage[]` records. These join provider id, surface id, plugin id, plugin owner, plugin status, availability, required capabilities, optional capabilities, and missing capabilities so provider and plugin owners can consume requirement coverage without reconstructing the provider/plugin join. `availability: optional-nested` means the parent surface can compose that independent plugin when available; it is not a parent-plugin dependency and it does not move nested semantics into the parent plugin. Consumer smokes can assert them with `--expect-provider-plugin-requirement `. Plugin-owner smokes should use the optional availability field when proving that Sai's required VN plugin is distinct from optional nested Norn or TeX surfaces. The runtime conformance pack is evidence-shaped, not fixture-shaped. Its `packs/runtime.json` document includes `runtimeTargets` so runtime repos can consume status, supported features, plugin support, command schema, lifecycle, capture status, world-surface lowering claims, and missing evidence without reading Eve's local parity manifest. The runtime-owner consumer smoke asserts EveUnity lifecycle stage status and pending release/test/capture proofs from the exported runtime record, plus release contract fields such as package name, artifact kind, tag pattern, and package root, plus Unity EditMode test runner contract fields such as runner script, package name, test assembly, and platform. It also asserts that web and Unity UI Toolkit claim their provider-advertised world-surface lowering targets. Split blockers are exported both as human-readable `blockers[]` and as typed `blockerRecords[]` / root `splitTargetBlockers[]` entries. Split-target consumers can assert blocker kind and subject with `--expect-split-target-blocker-record ` instead of scraping prose from handoff notes. Runtime split handoff move/source coverage is exported as `splitHandoffMoveCoverage[]`. Each record joins a split target, runtime id, handoff move set, destination owner, replacement proof, and source path status. `current` paths are Eve-incubated code that still needs to leave, `observed-provider` paths are provider-owned pressure sources such as Aetheria's current Electron client, and `replacement-required` records mark move sets where no generic runtime source exists yet. Consumer smokes can assert them with `--expect-split-handoff-move `. Runtime split handoff documents themselves use `gamecult.eve.runtime_split_handoff.v1`; the parity runner validates the handoff document shape and exports any `splitHandoffErrors` on the runtime record. Plugin, provider, and EveConformance handoff documents are also schema-backed: `gamecult.eve.plugin_handoff.v1`, `gamecult.eve.provider_handoff.v1`, and `gamecult.eve.conformance_handoff.v1` are exported through the schema catalog. Owner consumer smokes assert those schemas before trusting handoff paths. Runtime lifecycle records use `gamecult.eve.runtime_lifecycle.v1`. Standalone lifecycle documents such as `flutter/eve_parity/eveflutter-lifecycle.json` and embedded runtime capability lifecycle blocks validate against the same stage shape, and exported runtime records carry `lifecycleErrors`. Runtime shell output contracts are schema-backed too: `gamecult.eve.electron_shell_projection.v1` covers the Electron shell tree, and `gamecult.eve.tui_grid.v1` covers the compact terminal grid. The Electron and TUI runtime tests validate real lowered objects against those schemas. After generating the parity report, `run-parity-harness.ps1` copies `artifacts/conformance/latest` into `artifacts/conformance-consumer-smoke/export` and runs `tools/conformance/consume-export.mjs` against that copied layout. That smoke proves the conformance export can be consumed through its own index and pack files without reading `tools/parity/parity-manifest.json`. EveConformance handoff smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-eveconformance-handoff-smoke.ps1 ``` That script validates `tools/conformance/eveconformance-handoff.json` against the parity manifest and, when present, the generated conformance export. It checks the runner, schema, consumer-smoke, fixture-corpus move sets and the required core/plugin/provider/runtime pack families. Provider-owned consumer smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-aetheria-conformance-consumer-smoke.ps1 ``` That script runs the same export consumer from `E:\Projects\Aetheria` and asserts the provider pack, `aetheria-world` fixture, `aetheria` provider entry, `aetheria-world-command-replay` scenario, daemon game/editor surface-kind claims, and provider handoff path. Generated copies remain under Eve's `artifacts/aetheria-conformance-consumer-smoke` so the provider worktree does not become dirty merely by proving the boundary. Plugin owner handoff smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-plugin-handoff-smoke.ps1 ``` That script validates the Sai and Norn handoff manifests against their plugin manifests, advertisements, ABI fixtures, move-set paths, contract inputs, and external proofs. It also checks that the manifest and advertisement agree on the runtime-independent executable sidecar boundary: `gamecult.eve.plugin_abi.v1`, CultMesh/stdio transport, renderer independence, no provider-state mutation, provider-owned command acceptance, and `runtime.sidecar` process/protocol/schema fields. The plugin-owner conformance smoke also asserts those handoff paths, runtime boundary claims, and exported sidecar fields from the conformance export. Aetheria provider handoff smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-aetheria-provider-handoff-smoke.ps1 ``` That script validates `web/fixtures/aetheria-provider-handoff.json` against the provider advertisement and scenario. The handoff names the advertisement, interactive world surface fixture, provider scenario, Eve contracts, forbidden imports, and external proofs that must become Aetheria-owned before the provider pack leaves Eve incubation. EveFlutter consumer smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-eveflutter-conformance-consumer-smoke.ps1 ``` That script runs the export consumer from `flutter/eve_parity` and asserts the runtime pack, Sai provider fixture, Flutter runtime targets, and `EveFlutter` split target without reading `tools/parity/parity-manifest.json`. Split-target consumer smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-split-target-conformance-consumer-smoke.ps1 ``` That script asserts that EveFlutter, EveUnity, EveElectron, and EveTui are exported as incubating split targets, that their current split-readiness proofs are passed, and that their graduation blockers remain visible to consumers. A target being present is not enough; future owner repos must be able to consume why it is or is not ready to leave Eve incubation. EveElectron is intentionally pending: its handoff names the generic Electron shell boundary, while the Starbridge RTS client remains Aetheria-owned product code until a provider-agnostic shell exists. The same smoke asserts that the Aetheria Electron source paths named by the handoff currently exist as `observed-provider` sources, so the extraction pressure is visible without turning those paths into EveElectron authority. The Electron runtime now claims a narrow provider-advertised surface-tree command surface and exposes a typed capture request contract. It preserves embedded document slot identity in the generic shell projection, while packaged rendering, actual window capture, and plugin projection remain blockers. EveTui is now an active incubating runtime: it claims a lossy provider-advertised terminal-grid command surface, preserves embedded document slot identity in the grid artifact, projects Sai/Norn/TeX fallback shells, and attaches a typed JSON grid capture. Repo/package graduation and owner-repo capture production remain blockers. EveUnity includes both the active `unity-uitoolkit` package proof and the pending `unity-scene` runtime boundary; UI Toolkit support is not treated as full Unity scene/world lowering. The `unity-scene` runtime now claims a narrow scene graph command surface, preserves embedded document slot identity, and exposes a typed capture request contract, while actual scene capture, release, and plugin projection adapters remain explicit blockers. The Flutter widget smoke also exercises `EveProviderCatalog` and `EveProviderPicker` against a conformance-export-shaped provider list. That is the runtime-side provider picker proof; it consumes provider entries and plugin requirements without reading web fixture paths. Aetheria Unity package consumer smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-aetheria-unity-package-smoke.ps1 ``` That script checks that Aetheria's Unity package manifest consumes Eve's surface and UI Toolkit packages by file reference, verifies the generated `GameCult.Eve.UnityUIToolkit.csproj` includes all current Unity runtime source files, then builds the package through Aetheria's Unity-generated project. It is consumer-build evidence, not a replacement for runtime-owned Unity capture or release CI. Aetheria Unity EditMode test smoke: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-aetheria-unity-editmode-tests.ps1 ``` That script temporarily adds `org.gamecult.eve.unity-uitoolkit` to Aetheria's Unity `testables`, runs `GameCult.Eve.UnityUIToolkit.Tests` in Unity batchmode, writes XML and log artifacts under `artifacts/aetheria-unity-editmode`, and restores `Packages/manifest.json` before returning. The test asmdef uses Unity-style precompiled references for the Brokkr/CultMesh DLLs that Unity needs to resolve `GameCult.Mesh`; this complements the normal CultLib .NET/NuGet dependency story rather than replacing it. The runner proves the incubating package test lifecycle, not final EveUnity-owned release or capture. The exported runtime lifecycle records that runner contract so EveUnity can inherit the Unity-specific test proof without making Eve responsible for CultLib package distribution. Unity runtime lifecycle evidence: `packages/org.gamecult.eve.unity-uitoolkit/eve-runtime-capability.json` declares release, test, and capture lifecycle stages for the UI Toolkit runtime. The parity harness validates those lifecycle claims against `tools/parity/parity-manifest.json` and checks that declared evidence paths exist. The current lifecycle proof is deliberately split: - release: `tools/eveunity/eveunity-release-contract.mjs` builds a typed `gamecult.eve.runtime_release_request.v1` request from the runtime capability manifest and UPM package manifest; the tagged EveUnity release remains a split blocker; - test: package-owned EditMode tests run through Aetheria in Unity batchmode, and Aetheria can build the package through Unity's generated project; - capture: `tools/eveunity/eveunity-capture-contract.mjs` builds a typed `gamecult.eve.runtime_capture_request.v1` request from the runtime capability manifest and Aetheria provider advertisement; Unity editor or batchmode PNG capture remains a split blocker. TUI capture evidence is already typed even though EveTui remains incubating. `tools/evetui/evetui-capture-artifact.mjs` lowers the Aetheria world surface through `EveTuiShell` into `gamecult.eve.tui_grid.v1` and writes `artifacts/evetui-capture/latest/tui-grid.json`. The parity export includes that record as `runtime.captureArtifacts[]`; runtime-owner consumers can assert it without depending on Eve's source layout. The remaining blocker is owner-repo production of the same capture path, not absence of a cell-grid artifact. EveUnity split handoff evidence: ```powershell powershell -ExecutionPolicy Bypass -File .\scripts\run-eveunity-split-handoff-smoke.ps1 ``` That script validates `packages/org.gamecult.eve.unity-uitoolkit/eveunity-split-handoff.json` against the runtime capability manifest. The handoff names the package paths, lifecycle stages, Eve contracts, forbidden imports, and external proofs that must become EveUnity-owned before the runtime leaves incubation. The smoke runner writes: - `artifacts/parity-smoke//parity-smoke.md` - `artifacts/parity-smoke//parity-smoke.json` - one PNG per target that has a real capture body. ## Current Checks The first pass is semantic and fixture-driven: - compile local CultUI `.eve` fixtures; - load local JSON surface fixtures; - check provider id; - check required component kinds; - check minimum component counts where useful; - check required style tokens; - check required bindings; - check retained slider skins and control parts. - record the responsive viewport matrix used by screenshot smoke. - export `screenshotComparisonMetrics[]` records for structure, color tokens, bounding boxes, and text presence. This already catches the most embarrassing class of parity lie: a runtime or fixture claiming to render CultUI while the retained tree no longer contains the partitions, bindings, tokens, or slider anatomy the renderer is supposed to lower. Screenshot comparison metrics are intentionally not byte-identical image checks. Structure and color-token scores come from the authored surface contract; text-presence scores come from authored text-bearing nodes; bounding box records name whether authored layout boxes exist or whether a runtime still owes a capture/layout probe. A missing Unity, Electron, TUI, or Direct2D capture body therefore appears as `pending-capture`, not as fake visual parity. The web reference has the first measured bounding-box probes. The harness runs `scripts/run-web-reference-layout-probe-smoke.ps1`, which builds the browser lowerer and uses Chrome headless to write `artifacts/web-reference-layout-probe/latest/embedded-surface.json` and `artifacts/web-reference-layout-probe/latest/sai-vn.json` as `gamecult.eve.web_layout_probe.v1`. Parity consumes those artifacts and marks `web:embedded-surface:bounding-boxes` and `web:sai-vn:bounding-boxes` as `pass` with `evidenceLayer: runtime-layout-probe`. The fixture matrix also includes `embedded-surface`, which proves that nested CultMesh document slots survive the shared surface contract. The web reference, Flutter parity body, Unity UI Toolkit lowerer, iOS UIKit renderer, and native Android Kotlin dashboard renderer all need to understand `surface.slot`/`embeddedDocuments`. Rust participates at the CultMesh document sync layer: it must preserve the same `gamecult.eve.surface.v1` slot contract through typed document replication even when it is not painting pixels. Nested surface support is a required feature for every active GUI runtime in `tools/parity/parity-manifest.json`. Active runtimes list `requiredFixtures: ["embedded-surface"]` and `supportedFeatures: ["embeddedDocuments"]`; the semantic report prints both so a runtime cannot quietly fall out of the contract. Runtime entries also use `expectedSourceSymbols` for the renderer files that must contain the slot lowering path, so a runtime cannot keep a green body merely because its source file exists. The shared fixture is `web/fixtures/cultui-embedded-surface.json`, and renderer-specific tests should load that fixture rather than hand-authoring a local substitute. ## Runtime Status The harness tracks every target runtime: - Web reference: active semantic and screenshot target through Chrome headless using the provider query parameter. Required nested-surface evidence: `node --test web\eve-dsl.test.mjs` plus the `embedded-surface` fixture in `tools/parity/run-parity.mjs`. - Web responsive layout: Chrome headless emits phone, tablet, and desktop PNGs. - iOS / UIKit: screenshot target through SSH and EveCanvas' `/var/mobile/Library/EveCanvas/capture-request` service. Current iOS capture is fixed-device until a simulator or device-resize adapter exists. Required nested-surface evidence: run `scripts/run-parity-smoke.ps1 -ProviderId gamecult.eve.embedded-demo` against the device target. - Windows / Flutter: screenshot target through the Flutter parity golden smoke, with phone, tablet, and desktop goldens. Required nested-surface evidence: `flutter test --plain-name embedded_surface_fixture_contract` plus `scripts/capture-flutter-parity.ps1 -FixtureId gamecult.eve.embedded-demo`. - Linux / Flutter: screenshot target through Nightwing over SSH. The smoke stages `flutter/eve_parity`, runs Flutter goldens on Nightwing, and pulls back phone, tablet, and desktop PNGs. Required nested-surface evidence: `scripts/capture-linux-flutter-parity.ps1 -FixtureId gamecult.eve.embedded-demo`. - Android / Flutter: screenshot target through the same Flutter renderer, packaged as a debug APK, installed on Periwinkle through `adb`, and captured with optional `adb shell wm size`, orientation control, and `adb exec-out screencap`; the script restores device size and rotation after each viewport. Required nested-surface evidence: `scripts/capture-android-flutter-parity.ps1 -FixtureId gamecult.eve.embedded-demo`. - Android / Kotlin device edge: lightweight native CultMesh dashboard and sensor host. Required nested-surface evidence: `android/app/src/main/java/org/gamecult/eve/MainActivity.kt` renders `surface.slot` with a content description containing the embedded slot identity, and `node tools/parity/run-parity.mjs` reports `embeddedDocuments` support for `android-kotlin`. It does not consume plugin fixtures until EveAndroid grows a plugin projection adapter; Android Flutter is the Android-side plugin projection acceptance target. - Rust / CultMesh: typed document runtime rather than a CultUI renderer. Required nested-surface evidence: `cargo test -p cultnet-rs rust_preserves_cultui_embedded_surface_slots_through_typed_document_sync` in CultLib. - Fensalir Direct2D: specialized native target with a runtime-pack `gamecult.eve.surface.v1` adapter fixture; runtime-owned command smoke and Direct2D capture are still missing. Pending runtimes are allowed. Silent fake parity is not. ## Next Cuts 1. Extend runtime-owned image/layout probes to the Unity/Electron capture blockers and move EveTui's JSON grid capture path into the EveTui owner repo. 2. Normalize text scale and font loading across web, Flutter Android, Flutter desktop, and iOS. 3. Give iOS a real `vn.stage` scene compositor instead of compact stacked fixture lowering. 4. Replace Flutter golden screenshots with native window captures once the Flutter app body can emit a desktop frame without test harness help. 5. Add Direct2D frame capture once the Eve-to-`AquariumUiDocument` adapter exists.