feat: added supressor for static members on IUnionMembers

.config/dotnet-tools.json

@@ -17,7 +17,7 @@
       "rollForward": false
     },
     "purview.build": {
-      "version": "0.9.0",
+      "version": "0.9.1",
       "commands": [
         "purview-build"
       ],

.editorconfig

@@ -1,4 +1,4 @@
-# Purview.BuildSdk 2.0.0 - managed file, do not edit
+# Purview.BuildSdk 2.0.1 - managed file, do not edit
 #
 # This file is written by Purview.BuildSdk and is replaced whenever the SDK version changes. The version
 # on the first line is how the SDK recognises a file it owns: a .editorconfig without that marker is

AGENTS.md

@@ -84,17 +84,19 @@ The compiler's contract is not ours to redefine. Every generated union must sati
 ## Diagnostics rules
 
 - Prefix `UNI`. Every reported rule is in `AnalyzerReleases.Unshipped.md` (RS2008). Suppression
-  descriptors are not release-tracked. `UNI0000` and `UNI9001` are suppression descriptors, not rules: they
-  suppress `CA1034` and `CA1515` on a union's public nested `IUnionMembers` provider.
+  descriptors are not release-tracked. `UNI0000`, `UNI9001` and `UNI9002` are suppression descriptors, not
+  rules: `UNI0000` suppresses `CA1034` and `UNI9001` suppresses `CA1515` on a union's public nested
+  `IUnionMembers` provider, and `UNI9002` suppresses `CA1000` on a generic union's provider's static `Create`
+  members.
 - The blocking policy lives beside the descriptors (`DiagnosticLibrary.IsBlocking`); there is one policy
   for both hosts.
 - A rule is reported once. The analyzer reports per-target findings; the generator applies the same
   findings to `GeneratorResult.ShouldProcess` and reports only `UNI9000`.
 - Do not suppress warnings with `NoWarn`, `#pragma warning disable` or `SuppressMessage` in product code.
   The only suppressions kept repo-wide are `Purview.BuildSdk`'s `PDS0006` for `CA1815` on a union
-  declaration, this package's `UNI0000` `DiagnosticSuppressor` for `CA1034` and `UNI9001` for `CA1515` on a
-  union's `IUnionMembers` provider, and the deliberate `RSEXPERIMENTAL006` at the `ITypeSymbol.IsUnion` call
-  in a test.
+  declaration, this package's `UNI0000` `DiagnosticSuppressor` for `CA1034`, `UNI9001` for `CA1515` and
+  `UNI9002` for `CA1000` on a union's `IUnionMembers` provider, and the deliberate `RSEXPERIMENTAL006` at the
+  `ITypeSymbol.IsUnion` call in a test.
 
 ## Packaging rules
 

CHANGELOG.md

@@ -19,6 +19,11 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - A `UNI0000` `DiagnosticSuppressor` that suppresses `CA1034` and a `UNI9001` suppressor that suppresses
   `CA1515` on the public nested `IUnionMembers` provider the C# union contract requires. Both ship with the
   package's analyzer, so a surface-C union needs no suppression attribute.
+- A `UNI9002` `DiagnosticSuppressor` that suppresses `CA1000` (do not declare static members on generic
+  types) on a generic union's `IUnionMembers` provider static `Create` members. The members are the
+  contract's creation members and the provider is necessarily generic when the union is, so `CA1000` cannot
+  be satisfied without removing the union semantics. This lets the `purview-dev/results`
+  `ProvidedOption<T>.IUnionMembers` provider drop its `SuppressMessage` workaround.
 - A `UNI0005` code fix that makes the case type and every containing type public.
 
 ### Fixed

README.md

@@ -92,9 +92,11 @@ provider owns its one-line `Create` bodies, because a source generator cannot ad
 declared.
 
 The provider must be **public**, so a strict analyzer set reports `CA1034` (nested types should not be
-visible) and `CA1515` (public types should be internal). The package's `UNI0000` and `UNI9001` suppression
-descriptors handle both for an `IUnionMembers` provider nested in a union; no attribute is needed. The nested
-shape is mandated by the language, not a design choice.
+visible) and `CA1515` (public types should be internal). A generic union's provider is itself generic, so its
+static `Create` members are reported as `CA1000` (do not declare static members on generic types). The
+package's `UNI0000`, `UNI9001` and `UNI9002` suppression descriptors handle all three for an `IUnionMembers`
+provider nested in a union; no attribute is needed. The nested shape is mandated by the language, not a
+design choice.
 
 ### D — hand-written `Union<T1, T2>`
 
@@ -152,8 +154,9 @@ takes `int?`, and `TryGetValue(out int)` returns false for null — a null value
 
 The generated union is `CA1815`-clean: `Purview.BuildSdk`'s `PDS0006` suppresses the warning for a union
 declaration, because a union is matched by its active case rather than compared by value. Surface C is
-`CA1034`- and `CA1515`-clean: the package's `UNI0000` and `UNI9001` suppression descriptors cover the
-language-mandated public nested `IUnionMembers` provider. No `#pragma` is needed.
+`CA1034`-, `CA1515`- and `CA1000`-clean: the package's `UNI0000`, `UNI9001` and `UNI9002` suppression
+descriptors cover the language-mandated public nested `IUnionMembers` provider and its static `Create`
+members. No `#pragma` is needed.
 
 ## Diagnostics
 

docs/wiki/Diagnostics.md

@@ -26,10 +26,12 @@ whether it can emit and reports only `UNI9000`. A rule is reported once.
 Every error blocks its union: the generated constructors, storage and access members are one coherent shape,
 so there is no partial output. `UNI0015` is the only warning and does not block.
 
-`UNI0000` and `UNI9001` are **suppression descriptors**, not reported rules. `UNI0000` suppresses `CA1034`
-(nested types should not be visible) and `UNI9001` suppresses `CA1515` (public types should be internal) on a
-union's public nested `IUnionMembers` provider, which the C# union contract requires. Add either id to
-`NoWarn` to turn that suppression off.
+`UNI0000`, `UNI9001` and `UNI9002` are **suppression descriptors**, not reported rules. `UNI0000` suppresses
+`CA1034` (nested types should not be visible) and `UNI9001` suppresses `CA1515` (public types should be
+internal) on a union's public nested `IUnionMembers` provider, which the C# union contract requires.
+`UNI9002` suppresses `CA1000` (do not declare static members on generic types) on that provider's static
+`Create` members, which are the contract's creation members and are necessarily generic when the union is.
+Add any of these ids to `NoWarn` to turn that suppression off; a consumer should not need to.
 
 ## Details
 

docs/wiki/Getting-Started.md

@@ -67,8 +67,8 @@ Option<int> some = new Some<int>(42);
 ```
 
 A nested `IUnionMembers` provider is the alternative when another generator must see the case list; the
-provider is public, so the package's `UNI0000` and `UNI9001` suppressors handle the resulting `CA1034` and
-`CA1515`. See [Union Design](Union-Design.md).
+provider is public, so the package's `UNI0000`, `UNI9001` and `UNI9002` suppressors handle the resulting
+`CA1034`, `CA1515` and `CA1000`. See [Union Design](Union-Design.md).
 
 ## No generator
 

docs/wiki/Interop.md

@@ -29,10 +29,21 @@ follow-up in `purview-dev/results`.
 Do not hand-write the constructors to satisfy Results: the union generator would then treat the union as
 hand-written and the declared and existing lists would disagree (`UNI0012`/`UNI0014`).
 
+A hand-written `[Union]` union whose cases live on a nested `IUnionMembers` provider — the shape the Results
+tests use — needs no `SuppressMessage` attribute for `CA1000`. The package's `UNI9002` suppression descriptor
+answers the rule on the provider's static `Create` members, which are generic whenever the union is. See
+[Diagnostics](Diagnostics.md).
+
 ### Follow-up
 
 > `purview-dev/results`: add the two-generator integration test once `Purview.Unions` is on a CI-safe package
 > feed.
+>
+> `purview-dev/results`: once a `Purview.Unions` version carrying `UNI9002` is on the feed, bump
+> `PurviewUnionsVersion` in `Directory.Packages.props` and delete the `CA1000` `SuppressMessage` from
+> `ProvidedOption<T>.IUnionMembers` in `src/tests/SourceGenerator.UnitTests/GeneratedTestUnions.cs`. Verify by
+> raising `CA1000` to `warning` in a temporary project-local `.editorconfig` under that test project: the build
+> must report no `CA1000` for the provider's static `Create` members.
 
 ## Purview.Telemetry
 

docs/wiki/Union-Design.md

@@ -100,10 +100,10 @@ Design points:
 - **No equality, `ToString`, `Deconstruct`, `Match` or `Switch`** for generated unions in v1. A union is
   matched by its active case; `CA1815` is expected and `PDS0006` answers it. A `record` union gets the
   compiler's record equality over the tag and fields.
-- **Surface C is `CA1034`- and `CA1515`-clean.** The provider must be a public nested interface, so the
-  package's `UNI0000` and `UNI9001` suppression descriptors suppress the nesting and visibility warnings for
-  an `IUnionMembers` provider inside a union; a differently named nested type, or one outside a union, keeps
-  them.
+- **Surface C is `CA1034`-, `CA1515`- and `CA1000`-clean.** The provider must be a public nested interface,
+  so the package's `UNI0000`, `UNI9001` and `UNI9002` suppression descriptors suppress the nesting, visibility
+  and static-member-on-generic-type warnings for an `IUnionMembers` provider inside a union (for `CA1000`, on
+  its static `Create` members); a differently named nested type, or one outside a union, keeps them.
 - **Accessibility is never widened.** The partial declaration repeats the union's accessibility, and every
   case type must be at least as accessible as the union because a public creation member cannot expose a less
   accessible parameter type. An internal union can therefore use internal case types; a public union needs

package.json

@@ -1,6 +1,6 @@
 {
 	"name": "unions",
-	"version": "1.0.0-prerelease.2",
+	"version": "1.0.0-prerelease.3",
 	"license": "MIT",
 	"homepage": "https://purview.dev/projects/unions/",
 	"bugs": {

skills/purview-unions-diagnostics/SKILL.md

@@ -34,10 +34,12 @@ never reported twice.
 Every error blocks its union: the generated constructors, storage and access members are one coherent
 shape, so there is no partial output to emit. `UNI0015` is the only warning and does not block.
 
-`UNI0000` and `UNI9001` are **suppression descriptors**, not reported rules. `UNI0000` suppresses `CA1034`
-(nested types should not be visible) and `UNI9001` suppresses `CA1515` (public types should be internal) on a
-union's public nested `IUnionMembers` provider, which the C# union contract requires. Add either id to
-`NoWarn` to turn that suppression off.
+`UNI0000`, `UNI9001` and `UNI9002` are **suppression descriptors**, not reported rules. `UNI0000` suppresses
+`CA1034` (nested types should not be visible) and `UNI9001` suppresses `CA1515` (public types should be
+internal) on a union's public nested `IUnionMembers` provider, which the C# union contract requires.
+`UNI9002` suppresses `CA1000` (do not declare static members on generic types) on the provider's static
+`Create` members: they are the contract's creation members, and a generic union's provider is necessarily
+generic. Add any of these ids to `NoWarn` to turn that suppression off; you should not need to.
 
 ## `UNI0001` — not partial
 
@@ -104,7 +106,12 @@ The generator catches its own failures so one malformed union cannot discard eve
 
 There is deliberately no `NoWarn`/`#pragma` in this stack. The suppressions are `DiagnosticSuppressors`, not
 reported rules: `Purview.BuildSdk`'s `PDS0006` for `CA1815` on a union declaration, and this package's
-`UNI0000` for `CA1034` and `UNI9001` for `CA1515` on a union's nested `IUnionMembers` provider.
+`UNI0000` for `CA1034`, `UNI9001` for `CA1515` and `UNI9002` for `CA1000` on a union's nested
+`IUnionMembers` provider.
+
+`UNI9002` covers a generic union's provider static `Create` members, which `CA1000` reports on. A
+hand-written `[Union]` generic union's provider needs no `SuppressMessage` attribute for them; the
+suppression descriptor already answers the finding.
 
 ## Checklist
 

skills/purview-unions-modelling/SKILL.md

@@ -76,9 +76,11 @@ one-line `Create` bodies and delegates to the generated `CreateCaseN` methods. U
 want the case list visible to other generators.
 
 Because `IUnionMembers` must be **public**, a strict analyzer set reports `CA1034` and `CA1515` (nested types
-should not be visible; public types should be internal). The package's `UNI0000`/`UNI9001` suppression
-descriptors handle both for an `IUnionMembers` provider nested in a union; no attribute is needed. The nested
-shape is mandated by the language, not a design choice.
+should not be visible; public types should be internal). A generic union's provider is itself generic, so its
+static `Create` members are reported as `CA1000` (do not declare static members on generic types). The
+package's `UNI0000`/`UNI9001`/`UNI9002` suppression descriptors handle all three for an `IUnionMembers`
+provider nested in a union; no attribute is needed. The nested shape is mandated by the language, not a
+design choice.
 
 ### D — hand-written `Purview.Unions.Union<T1, T2>`
 

skills/purview-unions-quickstart/SKILL.md

@@ -111,7 +111,7 @@ for inspecting the declared source in isolation; it is not a way to make a faili
 | --- | --- | --- |
 | A | `[GenerateUnion(typeof(int), typeof(string))]` | Every case can be named in an attribute argument |
 | B | partial static factory signatures | A case names a type parameter |
-| C | a nested `IUnionMembers` provider | A generic union, or another generator must see the cases (the provider is public, but `UNI0000`/`UNI9001` suppress the resulting `CA1034`/`CA1515`) |
+| C | a nested `IUnionMembers` provider | A generic union, or another generator must see the cases (the provider is public, but `UNI0000`/`UNI9001`/`UNI9002` suppress the resulting `CA1034`/`CA1515`/`CA1000`) |
 | D | `Union<T1, T2>` | Exactly two cases, or no generator |
 
 ## Checklist