CNA-BUG-272: misc/cnj.md's native-extension table omits .gltf and .glb, its sourceFile matrix omits Texture3D, AnimationClip and Curve, and one sentence says CNA has no JSON object type although Json.hpp defines JsonValue

CNA snapshot 009d40f5  ·  Known Issues › Current bugs  ·  source links pinned to 009d40f5

CNA's .cnj design note lists no glTF extension although ModelTypeReader accepts .gltf and .glb, lists only three of the six readers that reject sourceFile in its capability matrix, and says CNA has no JSON object type, only hand-rolled helpers, although CNA/Internal/Json.hpp is a complete JsonValue parser that the note's own status block names.

Identifier

CNA-BUG-272

Category

Bug

Subsystem

Documentation & release tooling

Status

Open

Verified against

CNA 009d40f5 (009d40f5dd085c4e674d3479675fac84b12b3e0a)

Severity

Low (a triage suggestion, not a project priority)

Evidence basis

Source-verified: read at TARGET, not executed

Tests touching this area

Yes: see Current tests

Affected contract

misc/cnj.md: the native-extension table, the sourceFile capability matrix and the statements that CNA has no general JSON library or JSON object type

Expected behaviour

The design note that the code was built from states, for each reader, what the code enforces, and does not deny facilities the code has.

Actual behaviour at TARGET

cnj.md's table “Native extensions (the .cnj-absent fallback)” lists .png, .jpg/.jpeg, .bmp, .dds, .wav and .ogg/.mp3 and no glTF, and says a new native format is “just adding one more row here”, while ModelTypeReader::GetExtensions in ContentManager.cpp returns .cnj, .gltf and .glb. Its “sourceFile capability matrix” has rows for Texture2D, SoundEffect and TextureCube (supported) and for SpriteFont, Effect and Model (rejected), while RejectSourceFileForSelfContainedCnj is called for six self-contained readers: Texture3D, Effect, SpriteFont, AnimationClip, Curve and Model, so the rejecting readers Texture3D, AnimationClip and Curve have no row. In its paragraph on RegisterCnjLoader the note says “CNA has no JSON object type, only the hand-rolled string-scanning helpers”, and earlier it says the existing readers use hand-rolled helpers, “not a general JSON library”, and that a migration could “adopt a real JSON library at that point”. Json.hpp defines JsonValue, a complete parsed value for objects, arrays, strings, numbers, booleans and null, which ContentManager.cpp parses with ParseJson for the Texture3D, SpriteFont and stock-effect readers. The note's own status block names Json.hpp and says the envelope “parses via a real recursive-descent JSON parser”, so the note contradicts itself; the hand-rolled helpers still exist and other readers still use them.

Source locations

• misc/cnj.md — native-extension table, sourceFile capability matrix, the no-JSON-library statements
• modules/content/src/Xna/ContentManager.cpp — ModelTypeReader::GetExtensions and the RejectSourceFileForSelfContainedCnj call sites
• modules/content/include/CNA/Internal/Json.hpp — JsonValue, a complete parsed JSON value

Evidence

Read at 009d40f5; nothing was executed. The rest of the note is not re-audited here; CNA-BUG-245 covers a different statement in the same file (the content manifest). The sentence denying a JSON object type was true when RegisterCnjLoader was added (CNB-24) and became stale when Json.hpp arrived (CNB-35).

Focused reproduction

No focused reproduction is known. Nothing has been invented here; the evidence above is what exists.

Current tests

The behaviour the note describes is tested (CnjCapabilityMatrixTests.cpp for sourceFile rejection, RuntimeGltfModelTests.cpp for .gltf and .glb loading through ModelTypeReader, JsonTests.cpp for the parser); nothing compares the note's tables with the code.

Regression test

Add the glTF row and the three matrix rows, and correct the sentence about a JSON object type; or mark the note as a historical design sketch.

Blast radius

Contributors who read misc/cnj.md as the specification of the format: they would not learn that a model can be loaded from a native glTF file or which readers reject sourceFile.

Workaround

Read the site's CNJ documents Deep Dive, which states the enforced behaviour.