[6.0] Box.getReg

[SethDusek]

Closes #772

[coveralls]

Pull Request Test Coverage Report for Build 11100861612

Details

• 148 of 165 (89.7%) changed or added relevant lines in 26 files are covered.
• 9 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.2%) to 79.107%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
ergotree-ir/src/serialization/method_call.rs	11	13	84.62%
ergotree-ir/src/serialization/sigma_byte_reader.rs	4	6	66.67%
ergotree-interpreter/src/eval/extract_reg_as.rs	4	7	57.14%
ergotree-ir/src/mir/method_call.rs	9	12	75.0%
ergotree-interpreter/src/eval/sbox.rs	15	22	68.18%

Files with Coverage Reduction	New Missed Lines	%
ergotree-ir/src/ergo_tree.rs	1	85.31%
ergotree-ir/src/serialization/types.rs	4	84.67%
ergotree-ir/src/mir/expr.rs	4	81.12%

Totals
Change from base Build 10701623379:	0.2%
Covered Lines:	10863
Relevant Lines:	13732

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💛 - Coveralls