Rules
Rule index
Browse all analyzer rules with rule summaries, README examples, and extracted sample-app snippets.
DI001
`IServiceScope` instances created with `CreateScope()` or `CreateAsyncScope()` that are never disposed, including scopes whose only disposal call is hidden behind a conditional branch, switch section, loop, catch block, or after a branch exit that can bypass shared cleanup. DI001 recognizes predeclared nullable scope locals assigned conditionally when a later conditional-access, non-null-guarded, same-branch pre-exit, or `finally` disposal reliably closes ownership, while still reporting reassignment leaks and loop-created scopes that need per-iteration disposal.
Severity: Warning · Code fix: Yes
DI002
a service resolved from a scope that is returned or stored somewhere longer-lived, including services resolved through provider aliases, delegates that capture scoped services and then escape, scopes disposed later via `using (scope)`, and the same patterns inside constructors, accessors, local functions, lambdas, and anonymous methods.
Severity: Warning · Code fix: Yes
DI003
singleton services capturing scoped or transient dependencies, including constructor injection, `IEnumerable<T>` collection captures, known scoped framework services such as `IOptionsSnapshot<T>`, EF Core contexts and `DbContextOptions<TContext>` registrations from `AddDbContext(...)`, `AddDbContextFactory(...)`, `AddDbContextPool(...)`, and `AddPooledDbContextFactory(...)` including service/implementation overload self-registrations, and high-confidence factory paths such as inline delegates, stable local delegate factories, method-group factories, `GetServices<T>()`, keyed resolutions, and `ActivatorUtilities.CreateInstance(...)` without explicit constructor arguments.
Severity: Warning · Code fix: Yes
DI004
using a service after the scope that produced it has already ended, including services resolved through provider aliases, scoped collections from `GetServices<T>()` enumerated after disposal, explicit `Dispose()` / `DisposeAsync()`, scopes disposed later via `using (scope)`, and the same patterns inside constructors, accessors, local functions, lambdas, and anonymous methods.
Severity: Warning · Code fix: Yes
DI005
`CreateScope()` used in async flows where async disposal is needed, including async methods, lambdas, local functions, anonymous methods, and top-level programs that use `await`. Detection covers regular member access (`_scopeFactory.CreateScope()`) and conditional-access receivers (`_scopeFactory?.CreateScope()`, `_provider?.CreateScope()`) alike.
Severity: Warning · Code fix: Yes
DI006
`IServiceProvider` / `IServiceScopeFactory` / keyed provider stored in static fields or properties, including `Lazy<T>` wrappers around those provider types.
Severity: Warning · Code fix: Yes
DI007
resolving dependencies via `IServiceProvider` inside app logic.
Severity: Info · Code fix: No
DI008
transient services implementing `IDisposable`/`IAsyncDisposable` in risky patterns.
Severity: Warning · Code fix: Yes
DI009
open generic singleton registrations that depend on shorter-lived services, including `TryAddSingleton(...)`, `ServiceDescriptor.Singleton(...)`, keyed open-generic singleton registrations, and `IEnumerable<T>` constructor captures where the element service is shorter-lived.
Severity: Warning · Code fix: Yes
DI010
constructors with too many meaningful dependencies.
Severity: Info · Code fix: No
DI011
constructor injection of `IServiceProvider`, `IServiceScopeFactory`, or `IKeyedServiceProvider` in normal services.
Severity: Info · Code fix: No
DI012
- `TryAdd*` calls after an `Add*` already registered that service.
Severity: Info · Code fix: Yes
DI013
invalid service/implementation pairs that compile but fail at runtime, including generic, `typeof(...)`, keyed, named-argument, and `ServiceDescriptor` registrations.
Severity: Error · Code fix: Yes
DI014
root providers from `BuildServiceProvider()` that are never disposed, including local providers whose only manual disposal is conditional, catch-only, after reassignment to another provider, or after repeated creation inside a loop.
Severity: Warning · Code fix: Yes
DI015
registered services with direct or transitive constructor/factory dependencies that are not registered (including keyed and open-generic paths).
Severity: Warning · Code fix: Yes
DI016
`BuildServiceProvider()` calls while composing registrations (for example in `ConfigureServices`, `IServiceCollection` extension registration methods, registration lambdas, or builder-style `.Services` helper flows).
Severity: Warning · Code fix: No
DI017
constructor-injection cycles such as `A -> B -> A`, including longer transitive loops. It stays silent when constructor selection is ambiguous rather than guessing which path the container will choose.
Severity: Warning · Code fix: No
DI018
registrations whose implementation type cannot be constructed by the DI container, such as abstract classes, interfaces, static classes, delegate types registered without a factory, or concrete classes with no public constructors.
Severity: Warning · Code fix: No
DI019
scoped services, known scoped framework services such as `IOptionsSnapshot<T>`, EF Core contexts from `AddDbContext(...)`, `AddDbContextFactory(...)`, `AddDbContextPool(...)`, and `AddPooledDbContextFactory(...)` including service/implementation overload self-registrations, or services whose activation graph reaches a scoped service, resolved from a root `IServiceProvider` such as ASP.NET Core `app.Services`, ASP.NET test-host `factory.Services` / `server.Services`, Generic Host `host.Services`, nullable root-provider surfaces such as `app.Services!`, or a provider returned by `BuildServiceProvider()`.
Severity: Warning · Code fix: No