Separate type equality checker from contract update validator

[SupunS]

Description

This PR separates the AST type equality checking logic from the contract update validator, so that type equality checking can be re-used. No change is done to the checker's logic.

This is needed for moving the duplicate switch-case checking to the linter repo. Because the switch-case checking currently depends on the type-checker to do the type equality check. But once it is moved out from the type-checker, it no longer can rely on the checker. Instead, the same 'type equality check' can be performed using the AST only, similar to how it is done in the contract update validator.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit 3fd0b3e
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -benchmem -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Collapsed results for better readability

	old.txt	new.txt
	time/op		delta
CheckContractInterfaceFungibleTokenConformance-2	123µs ± 1%	125µs ± 1%	+1.48%	(p=0.003 n=7+5)
ContractInterfaceFungibleToken-2	36.8µs ± 0%	37.2µs ± 1%	+1.07%	(p=0.001 n=7+6)
InterpretRecursionFib-2	3.16ms ± 1%	3.19ms ± 0%	+1.04%	(p=0.004 n=6+5)
NewInterpreter/new_interpreter-2	1.01µs ± 0%	1.02µs ± 1%	+1.06%	(p=0.003 n=5+7)
NewInterpreter/new_sub-interpreter-2	2.12µs ± 3%	2.12µs ± 0%	~	(p=0.362 n=7+6)
ParseArray-2	7.56ms ± 1%	7.64ms ± 1%	+1.14%	(p=0.011 n=7+7)
ParseDeploy/byte_array-2	11.4ms ± 2%	11.6ms ± 2%	+2.13%	(p=0.002 n=7+7)
ParseDeploy/decode_hex-2	1.01ms ± 4%	1.02ms ± 3%	~	(p=0.209 n=7+7)
ParseFungibleToken/With_memory_metering-2	187µs ± 1%	191µs ± 3%	+1.96%	(p=0.038 n=7+7)
ParseFungibleToken/Without_memory_metering-2	140µs ± 1%	142µs ± 1%	+1.49%	(p=0.011 n=7+7)
ParseInfix-2	6.76µs ± 1%	6.83µs ± 1%	+1.04%	(p=0.008 n=7+6)
QualifiedIdentifierCreation/One_level-2	2.36ns ± 0%	2.36ns ± 0%	~	(p=0.965 n=6+5)
QualifiedIdentifierCreation/Three_levels-2	124ns ± 2%	124ns ± 1%	~	(p=0.509 n=7+6)
RuntimeFungibleTokenTransfer-2	1.12ms ±32%	1.18ms ±22%	~	(p=0.259 n=7+7)
RuntimeResourceDictionaryValues-2	5.89ms ± 3%	5.95ms ± 2%	~	(p=0.383 n=7+7)
ValueIsSubtypeOfSemaType-2	78.6ns ± 1%	79.1ns ± 2%	~	(p=0.345 n=7+6)
	alloc/op		delta
CheckContractInterfaceFungibleTokenConformance-2	67.0kB ± 0%	67.0kB ± 0%	~	(p=0.462 n=7+7)
ContractInterfaceFungibleToken-2	26.8kB ± 0%	26.8kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.51MB ± 0%	1.51MB ± 0%	~	(p=0.540 n=7+7)
NewInterpreter/new_interpreter-2	928B ± 0%	928B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.46kB ± 0%	1.46kB ± 0%	~	(all equal)
ParseArray-2	2.81MB ± 2%	2.80MB ± 2%	~	(p=0.805 n=7+7)
ParseDeploy/byte_array-2	4.38MB ± 3%	4.41MB ± 2%	~	(p=0.333 n=7+7)
ParseDeploy/decode_hex-2	214kB ± 0%	214kB ± 0%	~	(p=0.331 n=7+7)
ParseFungibleToken/With_memory_metering-2	36.3kB ± 0%	36.3kB ± 0%	~	(p=0.462 n=7+7)
ParseFungibleToken/Without_memory_metering-2	36.3kB ± 0%	36.3kB ± 0%	~	(p=0.878 n=7+6)
ParseInfix-2	2.17kB ± 0%	2.17kB ± 0%	~	(p=0.400 n=6+7)
QualifiedIdentifierCreation/One_level-2	0.00B	0.00B	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	64.0B ± 0%	64.0B ± 0%	~	(all equal)
RuntimeFungibleTokenTransfer-2	232kB ± 0%	232kB ± 0%	~	(p=0.383 n=7+7)
RuntimeResourceDictionaryValues-2	2.25MB ± 0%	2.25MB ± 0%	~	(p=0.456 n=7+7)
ValueIsSubtypeOfSemaType-2	48.0B ± 0%	48.0B ± 0%	~	(all equal)
	allocs/op		delta
CheckContractInterfaceFungibleTokenConformance-2	1.08k ± 0%	1.08k ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	461 ± 0%	461 ± 0%	~	(all equal)
InterpretRecursionFib-2	33.5k ± 0%	33.5k ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	13.0 ± 0%	13.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	42.0 ± 0%	42.0 ± 0%	~	(all equal)
ParseArray-2	70.0k ± 0%	70.0k ± 0%	~	(p=1.000 n=7+7)
ParseDeploy/byte_array-2	105k ± 0%	105k ± 0%	~	(p=1.175 n=6+7)
ParseDeploy/decode_hex-2	77.0 ± 0%	77.0 ± 0%	~	(all equal)
ParseFungibleToken/With_memory_metering-2	1.06k ± 0%	1.06k ± 0%	~	(all equal)
ParseFungibleToken/Without_memory_metering-2	1.06k ± 0%	1.06k ± 0%	~	(all equal)
ParseInfix-2	66.0 ± 0%	66.0 ± 0%	~	(all equal)
QualifiedIdentifierCreation/One_level-2	0.00	0.00	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	2.00 ± 0%	2.00 ± 0%	~	(all equal)
RuntimeFungibleTokenTransfer-2	4.19k ± 0%	4.19k ± 0%	~	(p=0.706 n=7+7)
RuntimeResourceDictionaryValues-2	37.5k ± 0%	37.5k ± 0%	~	(p=0.355 n=7+7)
ValueIsSubtypeOfSemaType-2	1.00 ± 0%	1.00 ± 0%	~	(all equal)

[turbolent]

I guess the code was literally just moved to the new file? Or where there any additional changes needed?

[SupunS]

Yes, just moved (and changed the receiver). No changes in the logic.

[turbolent]

Nice!