Scaffold a New Rule (TDD)

Arguments: $ARGUMENTS Example: /new-rule {RuleId} "Large struct passed by value"

Validation

1. Parse $1 as the rule ID and everything after as the title
2. Verify the rule ID matches the prefix defined in CLAUDE.md followed by a numeric ID — reject otherwise
3. Verify no existing descriptor matches id: "$1" in src/Spire.Analyzers/Descriptors.cs — abort if duplicate

Scaffolding (TDD order — tests and descriptor BEFORE analyzer)

4. Add descriptor to src/Spire.Analyzers/Descriptors.cs
   • Field name: {RuleId}_{TitlePascalCase}
   • Add in sequential order
5. Create test folder: tests/Spire.Analyzers.Tests/{RuleId}/
6. Create test case folder: tests/Spire.Analyzers.Tests/{RuleId}/cases/
7. Create shared preamble: tests/Spire.Analyzers.Tests/{RuleId}/cases/_shared.cs
   • Use global using directives (not plain using) — they apply to all case files since _shared.cs is a separate syntax tree in the same compilation
   • Always include: global using System;, global using System.Collections.Generic;, global using System.Threading.Tasks;, global using Spire.Analyzers;
   • Add rule-specific global using directives as needed (e.g., global using System.Buffers;)
   • Include shared type definitions relevant to the rule
8. Create test runner from template: tests/Spire.Analyzers.Tests/{RuleId}/{RuleId}Tests.cs
   • Replace {{RULE_ID}}, {{ANALYZER_TYPE}}
   • Inherits AnalyzerTestBase<TAnalyzer> — cases discovered at runtime, no [InlineData] needed
9. Create docs: docs/rules/{RuleId}.md
   • Replace {{RULE_ID}}, {{RULE_TITLE}}
   • Follow docs/style-guide.md for documentation style

Verify

10. Run dotnet build — must succeed with zero warnings
11. Report all created files

What this skill does NOT do

• Does NOT create the analyzer file — that is the implementer's job, after tests are written
• Does NOT create test case files — the lead writes those based on the rule plan's spec tables
• Only scaffolds the structure so the lead can immediately start writing test cases

Constraints

• Do NOT implement detection logic — the analyzer file is not created at this stage
• Do NOT modify existing analyzer files or descriptors (only append the new descriptor)
• Do NOT proceed if validation fails — report the error and stop