[Merged by Bors] - Fix cross-realm construction bugs

[jedel1043]

This Pull Request fixes test assert-throws-same-realm.js.

It changes the following:

• Handles global variables through the global object, instead of the context.
• Adds an active_function field to the vm, which is used as the NewTarget when certain builtins aren't called with new.
• Adds a realm_intrinsics field to Function.

[jedel1043]

Drafting because I want to see the impact this change makes in the test suite first.

[github-actions]

Test262 conformance changes

Test result	main count	PR count	difference
Total	94,343	94,343	0
Passed	71,170	71,163	-7
Ignored	17,386	17,386	0
Failed	5,787	5,794	+7
Panics	0	0	0
Conformance	75.44%	75.43%	-0.01%

Fixed tests (13):

test/harness/assert-throws-same-realm.js [strict mode] (previously Failed)
test/harness/assert-throws-same-realm.js (previously Failed)
test/harness/asyncHelpers-throwsAsync-same-realm.js [strict mode] (previously Failed)
test/harness/asyncHelpers-throwsAsync-same-realm.js (previously Failed)
test/built-ins/Function/internals/Construct/base-ctor-revoked-proxy-realm.js [strict mode] (previously Failed)
test/built-ins/Function/internals/Construct/base-ctor-revoked-proxy-realm.js (previously Failed)
test/built-ins/Function/internals/Construct/base-ctor-revoked-proxy.js [strict mode] (previously Failed)
test/built-ins/Function/internals/Construct/base-ctor-revoked-proxy.js (previously Failed)
test/built-ins/Symbol/keyFor/cross-realm.js [strict mode] (previously Failed)
test/built-ins/Symbol/keyFor/cross-realm.js (previously Failed)
test/built-ins/Symbol/for/cross-realm.js [strict mode] (previously Failed)
test/built-ins/Symbol/for/cross-realm.js (previously Failed)
test/built-ins/String/prototype/split/checking-by-using-eval.js [strict mode] (previously Failed)

Broken tests (20):

test/built-ins/Function/proto-from-ctor-realm-prototype.js [strict mode] (previously Passed)
test/built-ins/Function/proto-from-ctor-realm-prototype.js (previously Passed)
test/built-ins/Function/prototype/apply/this-not-callable-realm.js [strict mode] (previously Passed)
test/built-ins/Function/prototype/apply/this-not-callable-realm.js (previously Passed)
test/built-ins/Function/prototype/apply/argarray-not-object-realm.js [strict mode] (previously Passed)
test/built-ins/Function/prototype/apply/argarray-not-object-realm.js (previously Passed)
test/built-ins/Function/internals/Call/class-ctor-realm.js [strict mode] (previously Passed)
test/built-ins/Function/internals/Call/class-ctor-realm.js (previously Passed)
test/built-ins/AsyncGeneratorFunction/proto-from-ctor-realm-prototype.js [strict mode] (previously Passed)
test/built-ins/AsyncGeneratorFunction/proto-from-ctor-realm-prototype.js (previously Passed)
test/built-ins/GeneratorFunction/proto-from-ctor-realm-prototype.js [strict mode] (previously Passed)
test/built-ins/GeneratorFunction/proto-from-ctor-realm-prototype.js (previously Passed)
test/built-ins/RegExp/prototype/Symbol.split/splitter-proto-from-ctor-realm.js [strict mode] (previously Passed)
test/built-ins/RegExp/prototype/Symbol.split/splitter-proto-from-ctor-realm.js (previously Passed)
test/built-ins/String/prototype/valueOf/non-generic-realm.js [strict mode] (previously Passed)
test/built-ins/String/prototype/valueOf/non-generic-realm.js (previously Passed)
test/built-ins/String/prototype/toString/non-generic-realm.js [strict mode] (previously Passed)
test/built-ins/String/prototype/toString/non-generic-realm.js (previously Passed)
test/language/types/reference/get-value-prop-base-primitive-realm.js [strict mode] (previously Passed)
test/language/types/reference/get-value-prop-base-primitive-realm.js (previously Passed)

[codecov]

Codecov Report

Merging #2786 (8e302f6) into main (928d67b) will decrease coverage by 0.09%.
The diff coverage is 39.45%.

@@            Coverage Diff             @@
##             main    #2786      +/-   ##
==========================================
- Coverage   50.66%   50.57%   -0.09%     
==========================================
  Files         415      415              
  Lines       41063    41207     +144     
==========================================
+ Hits        20803    20841      +38     
- Misses      20260    20366     +106     

Impacted Files	Coverage Δ
boa_cli/src/debug/function.rs	0.00% <0.00%> (ø)
boa_cli/src/debug/mod.rs	0.00% <0.00%> (ø)
boa_cli/src/debug/realm.rs	0.00% <0.00%> (ø)
boa_engine/src/builtins/async_function/mod.rs	36.36% <0.00%> (-25.18%)	⬇️
...ngine/src/builtins/async_generator_function/mod.rs	44.00% <0.00%> (-24.75%)	⬇️
boa_engine/src/builtins/error/aggregate.rs	20.83% <0.00%> (-7.74%)	⬇️
boa_engine/src/builtins/generator/mod.rs	8.67% <0.00%> (-0.65%)	⬇️
boa_engine/src/builtins/generator_function/mod.rs	44.00% <0.00%> (-24.75%)	⬇️
boa_engine/src/builtins/intl/collator/mod.rs	5.39% <0.00%> (ø)
boa_engine/src/builtins/intl/date_time_format.rs	2.83% <0.00%> (-0.40%)	⬇️
... and 52 more

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[jedel1043]

Ok, this PR fixes half of the problem. The other half is that functions should also store the global_object and the global_this from the current realm, or the full realm in short. Otherwise, the function calls try to access properties from the context realm instead of their stored realm, which causes the regressions. To fix this we need to make realm shareable between functions.

There is a problem with this though: the realm is storing the full environment stack instead of only the global bindings. This means the vm needs to access the realm to access any binding at execution, which would be a disaster perf-wise if we wrapped the DeclarativeEnvironmentStack on a GcRefCell to make it shareable between functions.

Considering this, it'll be better to merge this as it is to reduce the size of the next PR, which will solve the second part of the problem.

[HalidOdat]

Looks good! Just some small suggestions :)

Also If the added TODOs are not going to be addressed in this PR, maybe we should create issues about them?

[jedel1043]

Also If the added TODOs are not going to be addressed in this PR, maybe we should create issues about them?

Ah, I'll probably solve those on the follow-up PR. I just added those to be easily searchable when I start working on it.

[Razican]

I'll try to use the new realm module in $boa you implement new realm creation in boa_tester when I return from vacation

I went through most filled and it looked good. If I have the time I'll finish the review today :)

[Razican]

Great work! LGTM

[HalidOdat]

Looks good to me! :)

[jedel1043]

bors r+

[bors]

Pull request successfully merged into main.

Build succeeded:

• Build and Test (macos-latest)
• Build and Test (windows-latest)
• Coverage
• Misc