chakra-core/ChakraCore

Make number serialization compatible with V8 (and new IETF spec draft)

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#149 opened on Jan 20, 2016

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BugCompatibilitySeverity: 2Suggestionhelp wanted

Description

In order to create signed JavaScript objects, you need to normalize data.

The JCS specification https://cyberphone.github.io/openkeystore/resources/docs/jcs.html#ECMAScript_Compatibility_Mode accomplish this "automatically" by relying on ES6 for property order (which Chakra implements), but also depends on the extended number formatting algorithm used in the Google V8 engine which after testing with 100 million of random and selected values appears to be used by Chrome, Firefox, and Safari as well as "node.js".

Browser test program: http://webpki.org/ietf/es6numberbrowsertest.html

10 million value test file: http://webpki.org/ietf/es6testfile.txt

Although JCS does not (a this stage) represent a standard, the core concept will most likely become a de-facto standard due to its simplicity.

Contributor guide

Tech stack
javascriptcpp
Domain
backendperformance
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
5
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
over 1 week
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
understanding of IEEE 754 double precisionknowledge of V8 number formatting algorithmfamiliarity with ChakraCore source codeC++ programming experience
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
15
Research direction
Examine the JCS specification and the linked browser test. Identify the specific number formatting differences between ChakraCore and V8 by comparing outputs using the provided test file. Look into ChakraCore's number serialization code (likely in lib/Runtime/NumberImplementation.cpp) and V8's implementation (src/numbers/conversions.cc). Implement the required changes to match V8's behavior, ensuring compatibility with the IETF draft.