Improve MA0192 HasFlag detection for zero comparisons#1161
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Add support for (value & flag) compared to 0 for ==, !=, is, and is not patterns when the enum flag is a single non-zero bit. Keep existing same-flag patterns, update fixer negation semantics, extend tests, and document the new behavior. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Updated [Meziantou.Analyzer](https://github.com/meziantou/Meziantou.Analyzer) from 3.0.85 to 3.0.89. <details> <summary>Release notes</summary> _Sourced from [Meziantou.Analyzer's releases](https://github.com/meziantou/Meziantou.Analyzer/releases)._ ## 3.0.89 NuGet package: <https://www.nuget.org/packages/Meziantou.Analyzer/3.0.89> ## What's Changed * Add opt-in MA0134 reporting for discarded awaitables by @meziantou in meziantou/Meziantou.Analyzer#1164 **Full Changelog**: meziantou/Meziantou.Analyzer@3.0.88...3.0.89 ## 3.0.88 NuGet package: <https://www.nuget.org/packages/Meziantou.Analyzer/3.0.88> ## What's Changed * Add MA0201 for zero-valued enum flag checks by @meziantou in meziantou/Meziantou.Analyzer#1163 **Full Changelog**: meziantou/Meziantou.Analyzer@3.0.87...3.0.88 ## 3.0.87 NuGet package: <https://www.nuget.org/packages/Meziantou.Analyzer/3.0.87> ## What's Changed * Fix MA0194 merge with existing and-patterns by @meziantou in meziantou/Meziantou.Analyzer#1162 **Full Changelog**: meziantou/Meziantou.Analyzer@3.0.86...3.0.87 ## 3.0.86 NuGet package: <https://www.nuget.org/packages/Meziantou.Analyzer/3.0.86> ## What's Changed * Improve MA0192 HasFlag detection for zero comparisons by @meziantou in meziantou/Meziantou.Analyzer#1161 **Full Changelog**: meziantou/Meziantou.Analyzer@3.0.85...3.0.86 Commits viewable in [compare view](meziantou/Meziantou.Analyzer@3.0.85...3.0.89). </details> [](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting `@dependabot rebase`. [//]: # (dependabot-automerge-start) [//]: # (dependabot-automerge-end) --- <details> <summary>Dependabot commands and options</summary> <br /> You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot show <dependency name> ignore conditions` will show all of the ignore conditions of the specified dependency - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself) </details> Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
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MA0192 currently catches
(value & Flag) == Flagstyle checks, but it misses the common zero-comparison form used to test bit presence. This makes the rule inconsistent and leaves validHasFlagsimplifications unreported.What changed
(value & Flag) == 0(value & Flag) != 0(value & Flag) is 0(value & Flag) is not 0== Flag,!= Flag,is Flag,is not Flag).== 0/is 0->!HasFlag,!= 0/is not 0->HasFlag).Notes for reviewers
The main non-obvious behavior is the single-bit guard for zero comparisons. This is intentional to avoid changing meaning for combined flag constants where
HasFlagand!= 0are not equivalent.