Veggerby.Units.Analyzers 0.2.1

Veggerby.Units.Analyzers

Roslyn analyzers for Veggerby.Units providing early feedback on unsafe or ambiguous unit usage.

These analyzers complement the core library’s deterministic dimensional algebra by surfacing issues directly in the IDE / CI before runtime.

Install

Add the analyzer package alongside the core library. Optionally add the code fixes package for IDE quick actions:

<ItemGroup>
  <PackageReference Include="Veggerby.Units" Version="$(VeggerbyUnitsVersion)" />
  <PackageReference Include="Veggerby.Units.Analyzers" Version="$(VeggerbyUnitsAnalyzersVersion)" PrivateAssets="all" />
  <PackageReference Include="Veggerby.Units.CodeFixes" Version="$(VeggerbyUnitsCodeFixesVersion)" PrivateAssets="all" />
</ItemGroup>

PrivateAssets="all" keeps analyzers/code fixes from flowing transitively to downstream consumers unless you intend that.

If you only want diagnostics in CI (no IDE code actions) omit the Veggerby.Units.CodeFixes reference.

Rules

VUNITS001 – Incompatible unit arithmetic

Disallows adding or subtracting measurements unless their units are structurally identical. Convert explicitly first if needed.

var length = new Int32Measurement(5, Unit.SI.m);
var time = new Int32Measurement(3, Unit.SI.s);
var bad = length + time; // VUNITS001

VUNITS002 – Ambiguous unit formatting

Some symbols (e.g. J, Pa, W, H) map to multiple quantity meanings. Use an explicit UnitFormat (e.g. UnitFormat.Qualified) to clarify output.

var energy = new Int32Measurement(1, Unit.SI.m*Unit.SI.m*Unit.SI.kg/(Unit.SI.s*Unit.SI.s));
var s1 = energy.ToString();          // VUNITS002
var s2 = energy.Format(UnitFormat.Qualified); // OK

Code Fix Support

Install Veggerby.Units.CodeFixes to enable:

• VUNITS001: Adds .ConvertTo(left.Unit) on the right operand of + / -.
• VUNITS002: Appends UnitFormat.Qualified to formatting invocation.

Both fixes support Fix All in Document / Project / Solution.

Suppression

Use standard pragma or GlobalSuppressions.cs when you intentionally violate a rule (rare; prefer fixing instead).

#pragma warning disable VUNITS002
var s = energy.ToString();
#pragma warning restore VUNITS002

Roadmap

• Enrich unit extraction for complex expression flows.
• Direct consumption of shared ambiguity registry (when public hook is finalized).
• Additional rules: affine misuse in arithmetic, redundant unit multiplications, dead dimension factors.

Contributing

1. Clone the repo.
2. Build & test: dotnet test (includes analyzer tests).
3. Add or update rule docs under docs/analyzers/ before submitting PRs.

License

MIT – see repository root LICENSE file.