Add configuration option for disabling selected built-in objects.

[egavrin]

To improve the configurability of the engine it's needed to provide build time flags for disabling selected built-ins.

Compact profile has possibility for this:

#ifdef CONFIG_ECMA_COMPACT_PROFILE
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_NUMBER_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_STRING_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_BOOLEAN_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_ERROR_BUILTINS
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_ARRAY_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_MATH_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_DATE_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_JSON_BUILTIN
// #define CONFIG_ECMA_COMPACT_PROFILE_DISABLE_REGEXP_BUILTIN
#endif /* CONFIG_ECMA_COMPACT_PROFILE */

//cc @seanshpark

[seanshpark]

+1

[akosthekiss]

With the new build system, this became possible

• either with the help of the new python build script, e.g.: tools/build.py --compile-flag="-DCONFIG_DISABLE_JSON_BUILTIN"
• or by parametrizing cmake directly, e.g.: cmake -DEXTERNAL_COMPILE_FLAGS='-DCONFIG_DISABLE_JSON_BUILTIN'.

Result with full build:

jerry> JSON.stringify({})
{}
jerry> JSON.parse("{}")
[object Object]

Result with selectively disabled JSON builtin:

jerry> JSON.parse("{}")
Script Error: unhandled exception: ReferenceError
jerry> JSON.parse("{}")
Script Error: unhandled exception: ReferenceError