Portable diffs

acorn-diff provides deterministic, in-memory diff primitives without depending on other ACORN crates or host services.

Its default std feature supports native applications. Disable default features and enable alloc for portable and WebAssembly-compatible consumers:

[dependencies]
acorn-diff = { version = "0.3.2", default-features = false, features = ["alloc"] }

Use unified_diff for labeled line-oriented output. Import DiffValue and call before.diff(&after) to create an RFC 6902 patch over two serde_json::Value instances. Generated patches use deterministic object-key ordering and the add, remove, and replace operation subset; the Rfc6902 trait exposes validated constructors for all six operation shapes.

ACORN-specific format detection and canonicalization live in acorn::analyzer::diff. Without --method, the acorn diff BEFORE AFTER command compares files in the same metadata standard and can emit unified output or JSON Patch. The command’s separate --method mode uses the portable acorn_core::similarity::compare facade; it does not change the acorn-diff package API.