Update AV2202: Prefer language syntax over explicit calls to underlying implementations#379
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Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
bkoelman
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Contributor
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Good addition, but it doesn't belong in this rule. This rule is about using language syntax instead of calling framework methods. Neither of these is a framework method. Also applies to the other addition down below.
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I don't understand the subtlety here? I don't want to suggest != null anymore and instead promote is not null
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I'm indifferent between the two styles, but it's good to choose one, so I'm fine with the addition. Just not in this rule, because that is about preferring language syntax over implementations (for example: int vs System.Int32). It doesn't belong in this rule because != and is not are both language syntax.
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Perhaps an idea to put this in a new rule that prescibes when to prefer pattern syntax (and when not)?
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Good idea. I'll do that.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Pull request overview
This PR refreshes guideline AV2202 so it reflects more modern C# idioms within the framework-usage rules, aligning the guidance with newer language syntax introduced in recent C# versions.
Changes:
- Retitles AV2202 and slightly rewrites its introductory rationale.
- Replaces older null-check examples with
is null/is not nullguidance. - Adds collection-expression examples, including initialization and
??=assignment.
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| Prefer (C# 14): |
| rule_id: 2202 | ||
| rule_category: dotnet-framework-usage | ||
| title: Prefer language syntax over explicit calls to underlying implementations | ||
| title: Prefer idiomatic C# over .NET Framework APIs |
dennisdoomen
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May 14, 2026
* Make sure the site works properly with Ruby 3.1 * Add AV0100: Understand the boundaries of your codebase (#300) * Add AV0105: Use design patterns to communicate intent (#301) * Add AV0110: Prefer composition over class inheritance (#302) * Add AV0110 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/0110.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Add AV0112: Apply the Principle of Least Surprise (#303) * Add AV0115 guideline (#304) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV0120: You Ain't Gonna Need It (YAGNI) (#305) * Add AV0120 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/0120.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Update _rules/0120.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Update _rules/0120.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Add AV0125: Don't Repeat Yourself (DRY) within boundaries (#306) * Update explanation of code boundaries and coupling Clarified the reasoning for preventing unnecessary coupling between components. * Add AV0135 guideline (#308) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1582 guideline (#318) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1608 guideline (#323) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1610 guideline (#324) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1708 guideline (#372) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1562 guideline (#368) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1800 guideline (#375) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1521 guideline (#361) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1520 guideline (#360) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1140 guideline (#356) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Remove AV1530: Don't change a loop variable inside a `for` loop or a collection in a `foreach` loop (#363) * Update AV1530 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Address review comments on AV1530: update title and add foreach collection example Co-authored-by: dennisdoomen <572734+dennisdoomen@users.noreply.github.com> Agent-Logs-Url: https://github.com/dennisdoomen/CSharpGuidelines/sessions/983488b6-53b6-4360-876c-4576219b2d4f * Remove AV1530 rule file entirely Co-authored-by: dennisdoomen <572734+dennisdoomen@users.noreply.github.com> Agent-Logs-Url: https://github.com/dennisdoomen/CSharpGuidelines/sessions/0ce85de6-5278-491a-87c7-607ef017b67b --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: dennisdoomen <572734+dennisdoomen@users.noreply.github.com> * Update AV1250 guideline (#358) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1115 guideline (#352) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1025 guideline (#351) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1020 guideline (#350) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1011 guideline (#348) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1010 guideline (#347) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1003 guideline (#345) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1618 guideline (#326) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1615: Prefer inline literals over constant variables in tests (#325) * Add AV1615 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/1615.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Update AV1835 guideline (#378) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1825 guideline (#377) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update AV1000: A class or interface should have a single purpose (#344) * Update AV1000 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/1000.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Remove AV2235 guideline (#342) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1602: Postfix test classes with `Specs` instead of `Tests` (#321) * Add AV1602 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Rename nested class Order_placement to OrderPlacement Renamed nested class for better readability. --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AV1605: Test behavior, not implementation details (#322) * Add AV1605 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/1605.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Add General Guidelines page (#385) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add Testability Guidelines page (#386) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update Links & Articles page (#387) * Update C ov er An dS ty le s page (#384) * Update AV2400 guideline (#382) * Split minor site updates from PR 298 (#383) * Add AV1600 guideline (#320) * Add AV1578 guideline (#317) * Update AV1706: Don't use abbreviations (#371) * Update AV1701 guideline (#370) * Update AV1755: Only use `Async` or `TaskAsync` as a suffix when a method has both synchronous and asynchronous versions (#374) * Clarify suffix usage for Async methods (#393) Follow-up for #374, to align with the replacement of "version" with "variant". * Update AV2305: Document all `public`, `protected` and `internal` types and members (#381) * Update AV2202: Prefer language syntax over explicit calls to underlying implementations (#379) * Update AV1820: Only use `async` for I/O-bound or long-running activities (#376) * Remove AV1580 guideline (#392) * AV0125: Consider duplicating simple logic across modules to reduce coupling (#369) * Update AV1554 guideline (#367) * Update AV1553 guideline (#366) * Update AV1546 guideline (#365) * Update AV1545: Don't use an `if`-`else` construct instead of a simple (conditional) assignment (#364) * Update AV1523 guideline (#362) * Update AV1500: Methods should not exceed 15 statements (#359) * Remove AV1230 guideline (#357) * Update AV1137: Keep parameters as specific and narrow as possible (#355) * Update AV1130: Return interfaces to unchangeable collections (#354) * Update AV1125: Don't expose stateful objects through static members (#353) * Update AV1013: Don't cast a base class to one of its derived classes (#349) * Add LSP example with polymorphism to AV1011 (#396) * Update AV1004: Use an interface rather than a base class to support multiple implementations (#346) * Remove AV2307 guideline (#343) * Remove AV2221 guideline (#341) * Remove AV2201 guideline (#339) * Remove AV1738 guideline (#338) Split from #298. Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Remove AV1737 guideline (#337) * Remove AV1568 guideline (#336) * Remove AV1532: Avoid nested loops (#334) * Remove AV1525 guideline (#333) * Remove AV1510 guideline (#332) * Remove AV1220 guideline (#331) * Add AV2308: Document what a member tries to do, not what it does or how it does it (#330) * Add AV2225: Use deconstruction to simplify variable assignments (#329) * Add AV1622: Test concrete implementations as part of a larger integration scope (#328) * Add AV1622 guideline Split from #298. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Update _rules/1622.md Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> * Add AV1620: Test reusable components separately from their consumers (#327) * Add AV1585: Make properties required when they must be set during initialization (#319) * Add AV1155: Use the `field` keyword in auto-properties when additional logic is needed (#316) * Add AV1150: Avoid local functions (#315) * Add AV1145: Use extension members to add behavior without modifying the original type (#314) * Add AV1035: Use primary constructors when they improve readability (#313) * Add AV1032: Consider a delegate instead of an interface with a single method (#312) * Add AV1030: Know when to use a record and when to use a class (#311) * Add AV1002: Only pass things to a constructor that most or all members need (#309) * Remove AV2207 guideline (#340) * Add AV0130: Apply the three pillars of object-oriented programming (#307) * Fix c# fencing to use csharp in assertion-comparison.html Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Remove severity field from all rules The severity rating is no longer used. This removes: - The severity front matter field from all 130 rule files - The severity icon <img> from the rule-category layout - The unused severity images (1.png, 2.png, 3.png) Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Dennis Doomen <dennis.doomen@greenchoice.nl> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Co-authored-by: Bart Koelman <10324372+bkoelman@users.noreply.github.com> Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: dennisdoomen <572734+dennisdoomen@users.noreply.github.com>
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This PR updates guideline AV2202.
It was split out of #298 so the change can be reviewed independently.
Files:
Part of the replacement for #298.