If WeaselJsonParser_create returns nullptr (e.g. negative stack size or allocation failure), set the existing error_ flag so that subsequent feed()/finish() calls return WeaselJson_REJECT instead of dereferencing the null parser_.
Also add a regression test in test_gen.cpp that constructs a RootBuilder with an invalid stack size and verifies it rejects without crashing.
Closes#36
The generated RootBuilder crashed (undefined behavior on std::vector::back())
when a JSON document's root value was a scalar or null while the schema
declared a non-nullable object or array root. The stack starts empty for
object/array roots, but cbStringData, cbNumberData, and cbBool called
stack_.back() without checking for an empty stack.
Add an empty-stack guard to the three scalar callbacks so they reject
instead of crashing. cbNull already handles the empty-stack case.
Regression tests added for:
- non-nullable object root rejecting null, boolean, number, and string roots
- nullable object root rejecting scalar roots
- nullable array root rejecting scalar roots
Closes#16
For array types whose items are nullable ({"type": ["T", "null"]}),
the generated builder previously called valueComplete() on cbNull() without
appending anything to the owning vector. Null entries were silently dropped,
so vector indices no longer matched JSON array indices.
Generate isArrayKind() / appendNull() helpers and have cbNull() append a
default-constructed element when the current frame is an array. For
std::optional<T> items this appends an empty optional; for std::unique_ptr<T>
items it appends a null pointer. Add nullable string/integer array fields to
the example schema and test coverage to verify indices are preserved.
Fixes#5
JSON Schema's 'integer' type matches any number with a zero fractional
part, but the generated builder rejected forms like 1e3 or 2.0 because it
only ran std::from_chars<int64_t>. Keep that exact path for plain integer
literals (so large values near INT64_MAX stay exact), and fall back to
parsing as double for the rest, requiring an integral value within int64
range. Add <cmath> for std::trunc and cover the new cases in test_gen.
Generates a C++ type and a streaming builder parser from a JSON Schema,
built on weaseljson. The builder copies incoming bytes directly into their
final destinations in the result struct (no intermediate DOM) and hands
back ownership via take() once parsing completes.
Supports objects/structs, required vs optional (std::optional) fields,
nullable types, string enums, arrays, $ref including recursion (broken
with unique_ptr), and additionalProperties (strict reject or skip).
Unsupported schema constructs are rejected at generation time; schema
violations are rejected at parse time.
weaselbot
andrew