Commit Graph

3 Commits

Author SHA1 Message Date
Sam McCall e6057bc689 [Support] Harded JSON against invalid UTF-8.
Parsing invalid UTF-8 input is now a parse error.
Creating JSON values from invalid UTF-8 now triggers an assertion, and
(in no-assert builds) substitutes the unicode replacement character.
Strings retrieved from json::Value are always valid UTF-8.

llvm-svn: 336657
2018-07-10 11:51:26 +00:00
Sam McCall d93eaeb7c3 [Support] Make JSON handle doubles and int64s losslessly
Summary:
This patch adds a new "integer" ValueType, and renames Number -> Double.
This allows us to preserve the full precision of int64_t when parsing integers
from the wire, or constructing from an integer.
The API is unchanged, other than giving asInteger() a clearer contract.

In addition, always output doubles with enough precision that parsing will
reconstruct the same double.

Reviewers: simon_tatham

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46209

llvm-svn: 336541
2018-07-09 12:16:40 +00:00
Sam McCall 6be3824721 Lift JSON library from clang-tools-extra/clangd to llvm/Support.
Summary:
This consists of four main parts:
 - an type json::Expr representing JSON values of dynamic kind, which can be
   composed, inspected, and modified
 - a JSON parser from string -> json::Expr
 - a JSON printer from json::Expr -> string, with optional pretty-printing
 - a convention for mapping json::Expr <=> native types (fromJSON/toJSON)
   Mapping functions are provided for primitives (e.g. int, vector) and the
   ObjectMapper helper helps implement fromJSON for struct/object types.

Based on clangd's usage, a couple of places I'd appreciate review attention:
 - fromJSON returns only bool. A richer error-signaling mechanism may be useful
   to provide useful messages, or let recursive fromJSONs (containers/structs)
   do careful error recovery.
 - should json::obj be always explicitly written (like json::ary)
 - there's no streaming parse API. I suspect there are some simple wins like
   a callback API where the document is a long array, and each element is small.
   But this can probably be bolted on easily when we see the need.

Reviewers: bkramer, labath

Subscribers: mgorny, ilya-biryukov, ioeric, MaskRay, llvm-commits

Differential Revision: https://reviews.llvm.org/D45753

llvm-svn: 336534
2018-07-09 10:05:41 +00:00