NEWS.md
In s7contract: Behavioral Contracts and Generative Laws for 'S7'

s7contract 0.2.3

Source builds exclude local test.arrows data files.

s7contract 0.2.2

Union requirements cover every concrete dispatch signature. Checked calls preserve lexical generic defaults, shared argument promises, and return visibility.
Trait registrations use descriptor identity. Deserialized descriptors require registration in the current session; register union targets one member at a time.
Added generative laws with new_law(), structured results from check_law(), and one-result tinytest integration through expect_law().
Generators support integers, finite doubles, constants, mapping, independent products, and nested vectors. gen_sample() selects positions without replacement; gen_subsequence() preserves source order.
Added dependent generation with gen_bind(), weighted gen_element() and gen_choice(), and size control with gen_sized() and gen_resize(). Dependent shrinks rebuild valid inputs with a captured local seed.
Added gen_recursive() for nested structures, gen_example() for reproducible inspection, and gen_no_shrink() to hold values fixed during shrinking.
Shrinking constructs candidates lazily and preserves generator constraints. Results report the last accepted failing candidate, shrink_status, and shrink_condition. Errors during shrinking preserve the original and last failing examples. Vector shrinking removes chunks before shrinking elements; double shrinking moves toward an explicit origin until rounding stops progress.
Added case classification and minimum observed coverage to new_law() and new_state_law(). Results retain counts and proportions; unmet requirements produce insufficient_coverage after the requested passing cases. Discards, errors, and shrink evaluations do not contribute to coverage.
Added sequential protocol laws with new_command(), gen_commands(), and new_state_law(). Commands run against a reference model with fresh fixtures, dependency-preserving shrinking, and original and reduced failure traces. The key/value example tests two S7 implementations and a faulty reset method.
Standardized law runs on Mersenne-Twister with Inversion normals and Rejection sampling, and recorded run parameters for replay. Box-Muller callers are rejected before changing RNG state because its cached normal draw cannot be restored through R's public API.
Integer counts, bounds, and seeds are validated before conversion. Discarded cases advance generator size and count toward the discard budget.
Added reusable laws for numeric vectors and ReadDepth, generated Maybe values and functions, UTF-8 store keys, and whole-day calendar intervals. Examples demonstrate faults in slicing, rounding, key truncation, reset, monad composition, and endpoint inclusion.

s7contract 0.1.0

Renamed the primary new_interface() requirement argument to generics; methods remains a compatibility alias.
Tightened interface and trait requirements to require S7 generics created with S7::new_generic().
Added optional progressive argument and return checks for interface requirements and trait methods, including with() and %::% evaluation syntax.
Reworked contract descriptor objects as internal S7 classes throughout.
Added a Haskell-style Maybe/monad dictionary example to the interface and trait vignette.
Added CRAN-facing vignettes with number-like, vector-like, and bioinformatics container examples.
Added CRAN submission comments and metadata updates for vignette building.
Fixed impl_trait() so failed S7 method registration no longer leaves a stale trait implementation record.
Preserved explicit NULL associated item values and allowed subtraits to retrieve inherited associated items.
Added regression tests for trait registration failure and associated metadata edge cases.
Simplified the README to keep the Go/Rust analogies clearly scoped to runtime S7 helpers.