Add boxed variant comparisons

[jpschorr]

This PR builds on #540 and adds comparisons and comparison tests.

There are still todos and some additional test failures that will be addressed by future PRs that add functionality.

To see the ultimate end-point of this integration, refer to #536 and note the test coverage and conformance test results.

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Attention: Patch coverage is 36.32959% with 170 lines in your changes missing coverage. Please review.

Project coverage is 80.08%. Comparing base (cc421cf) to head (9cba19d).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
extension/partiql-extension-ion/src/decode.rs	25.24%	77 Missing ⚠️
extension/partiql-extension-ion/src/boxed_ion.rs	36.25%	49 Missing and 2 partials ⚠️
partiql-value/src/boxed_variant.rs	13.04%	20 Missing ⚠️
partiql-value/src/variant.rs	53.12%	15 Missing ⚠️
partiql-value/src/value.rs	44.44%	3 Missing and 2 partials ⚠️
partiql-value/src/comparison.rs	0.00%	2 Missing ⚠️

❌ Your patch status has failed because the patch coverage (36.32%) is below the target coverage (85.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #542      +/-   ##
==========================================
- Coverage   80.49%   80.08%   -0.42%     
==========================================
  Files          95       95              
  Lines       20266    20465     +199     
  Branches    20266    20465     +199     
==========================================
+ Hits        16314    16390      +76     
- Misses       3520     3640     +120     
- Partials      432      435       +3     

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[github-actions]

Conformance comparison report

	Base (cc421cf)	a332d66	+/-
% Passing	85.72%	86.31%	0.59%
✅ Passing	5511	5549	38
❌ Failing	918	880	-38
🔶 Ignored	0	0	0
Total Tests	6429	6429	0

Number passing in both: 5511

Number failing in both: 880

Number passing in Base (cc421cf) but now fail: 0

Number failing in Base (cc421cf) but now pass: 38

The following test(s) were previously failing but now pass. Before merging, confirm they are intended to pass:

Click here to see

• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_result_false_
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_blob_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_struct_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_clob_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_1_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_null_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_missing_result_true_
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_struct_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_symbol_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_null_result_true_
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_result_false
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_int_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_decimal_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_sexp_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_symbol_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_null_result_true_
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_bool_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_list_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_missing_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_result_false_
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_int_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_string_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_1_result_true_
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_clob_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_null_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::permissive_exists_valid_cases_param_missing_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_1_result_true_
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_missing_result_true_
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_sexp_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_bool_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_list_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_decimal_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::strict_null_comparison_sql_null_blob_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_1_result_true
• partiql_tests::eval::ion::primitives::primitives::null::null::permissive_null_comparison_sql_null_string_is_null_result_true
• partiql_tests::eval::ion::primitives::primitives::functions::exists::exists::strict_exists_valid_cases_param_result_false

[jpschorr]

There are some lingering warnings of the form ...is more private than the item...

They are fixed in #544 : for example: https://github.com/partiql/partiql-lang-rust/pull/544/files#diff-b95d0de35899342f30d2531c8cd3728a958d846d163f0c154c204f7aeb8979ceL112