Reject assisted injection in cycles

Partial solution to #286

Author: evant

kotlin-inject-compiler/core/src/main/kotlin/me/tatarka/inject/compiler/TypeResultResolver.kt

@@ -463,7 +463,10 @@ class TypeResultResolver(private val provider: AstProvider, private val options:
         args: List<AstType>,
         result: (context: Context) -> TypeResultRef,
     ): TypeResult {
-        cycleDetector.delayedConstruction()
+        // The current cycle resolution does not handle args because it re-uses the same instance.
+        if (args.isEmpty()) {
+            cycleDetector.delayedConstruction()
+        }
         val context = context.copyNameAllocator()
         val namedArgs = args.mapIndexed { i, arg ->
             arg to context.nameAllocator.newName("arg$i")

kotlin-inject-compiler/test/src/test/kotlin/me/tatarka/inject/test/FailureTest.kt

@@ -797,4 +797,29 @@ class FailureTest {
             contains("Cannot apply scope: @MyScope to type with @Assisted parameters: [arg: String]")
         }
     }
+
+    @ParameterizedTest
+    @EnumSource(Target::class)
+    fun fails_if_assisted_injection_is_used_in_a_cycle(target: Target) {
+        val projectCompiler = ProjectCompiler(target, workingDir)
+
+        assertFailure {
+            projectCompiler.source(
+                "MyComponent.kt",
+                """
+                import me.tatarka.inject.annotations.Component
+                import me.tatarka.inject.annotations.Assisted
+                import me.tatarka.inject.annotations.Inject
+                
+                @Inject class Cycle(factory: (Int) -> Cycle, @Assisted arg: Int)        
+                
+                @Component abstract class MyComponent {
+                    abstract val cycleFactory: (Int) -> Cycle
+                }  
+                """.trimIndent()
+            ).compile()
+        }.output().all {
+            contains("Cycle detected")
+        }
+    }
 }