WHIZ058: GUID Call Intercepted¶

Verified by tests

GuidInterceptorGeneratorTests, ThirdPartyGuidInterceptionTests — library CI run #31657041675 (2026-08-13)

Severity: Info Category: Source Generation

Description¶

This informational diagnostic is reported when the GuidInterceptorGenerator identifies a GUID creation call eligible for interception and wraps it with TrackedGuid. This enables metadata tracking for the generated GUID.

The diagnostic itself is reported whenever the generator finds an interceptable call — even if WhizbangGuidInterceptionEnabled is not set. However, the actual interceptor code (the TrackedGuid wrapping) is only generated when the MSBuild property WhizbangGuidInterceptionEnabled=true is set.

Calls inside Whizbang.* namespaces are never intercepted (the library controls its own GUID creation), so no WHIZ058 is reported for them.

Diagnostic Message¶

Intercepted System.Guid.NewGuid() at /src/MyApp/OrderService.cs:15 - wrapped with TrackedGuid for metadata tracking

What Gets Intercepted¶

The following GUID creation methods are intercepted:

Method	Metadata
`Guid.NewGuid()`	`Version4 \\| SourceMicrosoft`
`Guid.CreateVersion7()`	`Version7 \\| SourceMicrosoft`
`CombGuidIdGeneration.NewGuid()`	`Version7 \\| SourceMarten`
`UUIDNext.Uuid.NewSequential()`	`Version7 \\| SourceUuidNext`
`UUIDNext.Uuid.NewDatabaseFriendly()`	`Version7 \\| SourceUuidNext`
`Medo.Uuid7.NewUuid7()`	`Version7 \\| SourceMedo`

Enabling Interception¶

Add to your project file:

Enabling Interception

<PropertyGroup>
  <WhizbangGuidInterceptionEnabled>true</WhizbangGuidInterceptionEnabled>
</PropertyGroup>

Suppressing This Diagnostic¶

If you want to suppress interception for specific code:

Method-Level Suppression¶

Method-Level Suppression

using Whizbang.Core;

[SuppressGuidInterception]
public Guid CreateRawGuid() {
  return Guid.NewGuid();  // Not intercepted, no WHIZ058
}

Class-Level Suppression¶

Class-Level Suppression

[SuppressGuidInterception]
public class TestFixtures {
  // All GUID calls in this class are not intercepted
}

Pragma Suppression¶

Wrapping a call in #pragma warning disable WHIZ055 (or WHIZ056) disables interception entirely for that call — no interceptor is generated and neither WHIZ058 nor WHIZ059 is reported:

Pragma Suppression

#pragma warning disable WHIZ055
var id = Guid.NewGuid();  // Not intercepted, no WHIZ058
#pragma warning restore WHIZ055

Note: #pragma warning disable WHIZ058 does not stop interception — the generator keys pragma suppression off the analyzer IDs WHIZ055/WHIZ056, not WHIZ058.

Project-Level Suppression¶

Hides the WHIZ058 informational message from build output. This does not stop interception — use [SuppressGuidInterception] or the WHIZ055/WHIZ056 pragma for that:

Project-Level Suppression

<PropertyGroup>
  <NoWarn>$(NoWarn);WHIZ058</NoWarn>
</PropertyGroup>

Why This Matters¶

TrackedGuid interception provides: - Version tracking - Know if a GUID is v4 (random) or v7 (time-ordered) - Source tracking - Know which library generated the GUID - Runtime validation - Validate that time-ordered GUIDs are used where required - Debugging - Trace GUID origins in complex systems

WHIZ059 - Interception suppressed (when [SuppressGuidInterception] is used)
WHIZ055 - Warning for Guid.NewGuid() usage (analyzer, separate from interception)
WHIZ056 - Warning for Guid.CreateVersion7() usage (analyzer)