Commit Graph

2 Commits

Author SHA1 Message Date
Niels Lohmann
ea5a1caf28 Address the clang-tidy findings of the view's parser
- tables as std::array; the frames of the first 64 levels stay a C array
  (not initialized on purpose, NOLINT)
- \u escapes are decoded with the library's hex_codepoint() instead of a
  second table
- the parse failure is private, with an accessor; the special member
  functions of the builder are all declared
- no nested conditional operators; explicit parentheses; a repeated
  branch body merged; auto for casts
- the test's C arrays, fixed seed, and escaped literals are marked, as in
  the other tests

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-09-29 03:49:31 +02:00
Niels Lohmann
a14ac39bdd Add the one-pass parser of json_view (internal)
The builder parses JSON text in one pass into the node index: strings and
numbers stay in the source (escaped strings are decoded into an arena),
integers are converted while their digits are in cache, and floats keep
their digit layout for a later conversion. It accepts exactly what
json::parse accepts, for every combination of comments and trailing commas,
with and without a terminating NUL, and with JSON_STRICT_NUL_HANDLING.

Parse state lives in a local cursor whose address never escapes, so that it
stays in registers; out-of-line helpers (errors, regrowth, escapes,
comments) are members of the builder and get the positions they need. The
value dispatch is expanded once for array elements and once for member
values. Literals are compared with memcmp and words read in a fixed byte
order, so nothing depends on the platform's byte order. Error messages come
with the public classes.

Tests (unit-json_view_builder.cpp): accept/reject and values against
json::parse for handwritten, generated, and damaged documents under all
option combinations, from std::string and from exact-size buffers (no read
past the input under AddressSanitizer), deep nesting up to 100,000 levels,
NUL/BOM/whitespace cases, and the test-suite files.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-09-29 03:49:30 +02:00