Optimize exception messages to contain helpful debug information

api/src/main/kotlin/com/google/devtools/ksp/utils.kt

@@ -132,7 +132,7 @@ fun KSClassDeclaration.getAllSuperTypes(): Sequence<KSType> {
                 is KSClassDeclaration -> sequenceOf(resolvedDeclaration)
                 is KSTypeAlias -> sequenceOf(resolvedDeclaration.findActualType())
                 is KSTypeParameter -> resolvedDeclaration.getTypesUpperBound()
-                else -> throw IllegalStateException()
+                else -> throw IllegalStateException("unhandled type parameter bound $ExceptionMessage")
             }
         }
 
@@ -148,7 +148,7 @@ fun KSClassDeclaration.getAllSuperTypes(): Sequence<KSType> {
                         is KSClassDeclaration -> it.getAllSuperTypes()
                         is KSTypeAlias -> it.findActualType().getAllSuperTypes()
                         is KSTypeParameter -> it.getTypesUpperBound().flatMap { it.getAllSuperTypes() }
-                        else -> throw IllegalStateException()
+                        else -> throw IllegalStateException("unhandled super type kind $ExceptionMessage")
                     }
                 }
         )
@@ -243,3 +243,5 @@ fun KSDeclaration.isVisibleFrom(other: KSDeclaration): Boolean {
     }
 
 }
+
+const val ExceptionMessage = ",please file a bug at https://github.com/google/ksp/issues/new"

api/src/main/kotlin/com/google/devtools/ksp/visitor/KSValidateVisitor.kt

@@ -1,5 +1,6 @@
 package com.google.devtools.ksp.visitor
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.google.devtools.ksp.symbol.*
 
 class KSValidateVisitor(private val predicate: (KSNode, KSNode) -> Boolean) : KSDefaultVisitor<Unit, Boolean>() {
@@ -16,7 +17,7 @@ class KSValidateVisitor(private val predicate: (KSNode, KSNode) -> Boolean) : KS
     }
 
     override fun defaultHandler(node: KSNode, data: Unit): Boolean {
-        throw IllegalStateException("unhandled validation condition, please file a bug at https://github.com/google/ksp/issues/new")
+        throw IllegalStateException("unhandled validation condition $ExceptionMessage")
     }
 
     override fun visitTypeReference(typeReference: KSTypeReference, data: Unit): Boolean {

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/processing/impl/CodeGeneratorImpl.kt

@@ -46,7 +46,7 @@ class CodeGeneratorImpl(
         val file = File(path)
         val parentFile = file.parentFile
         if (!parentFile.exists() && !parentFile.mkdirs()) {
-            throw IllegalStateException()
+            throw IllegalStateException("failed to make parent directories.")
         }
         file.writeText("")
         fileMap[path] = file

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/processing/impl/ResolverImpl.kt

@@ -18,10 +18,7 @@
 
 package com.google.devtools.ksp.processing.impl
 
-import com.google.devtools.ksp.KspExperimental
-import com.google.devtools.ksp.closestClassDeclaration
-import com.google.devtools.ksp.isOpen
-import com.google.devtools.ksp.isVisibleFrom
+import com.google.devtools.ksp.*
 import com.intellij.openapi.project.Project
 import com.intellij.psi.*
 import com.intellij.psi.impl.source.PsiClassReferenceType
@@ -442,7 +439,7 @@ class ResolverImpl(
                     return getKSTypeCached(resolveJavaType(type.psi), type.element.typeArguments, type.annotations)
                 }
             }
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unable to resolve type for $type $ExceptionMessage")
         }
     }
 
@@ -454,13 +451,14 @@ class ResolverImpl(
                 is KtClassOrObject -> KSClassDeclarationImpl.getCached(psi)
                 is PsiClass -> KSClassDeclarationJavaImpl.getCached(psi)
                 is KtTypeAlias -> KSTypeAliasImpl.getCached(psi)
-                else -> throw IllegalStateException()
+                else -> throw IllegalStateException("Unexpected psi type: ${psi.javaClass} $ExceptionMessage")
             }
         } else {
             when (descriptor) {
                 is ClassDescriptor -> KSClassDeclarationDescriptorImpl.getCached(descriptor)
                 is TypeParameterDescriptor -> KSTypeParameterDescriptorImpl.getCached(descriptor)
-                else -> throw IllegalStateException()
+                null -> throw IllegalStateException("Failed to resolve descriptor for $kotlinType")
+                else -> throw IllegalStateException("Unexpected descriptor type: ${descriptor.javaClass} $ExceptionMessage")
             }
         }
     }

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSAnnotationDescriptorImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.binary
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.intellij.psi.JavaPsiFacade
 import com.intellij.psi.PsiAnnotationMethod
 import org.jetbrains.kotlin.descriptors.ClassConstructorDescriptor
@@ -122,6 +123,6 @@ fun ValueParameterDescriptor.getDefaultValue(): Any? {
         }
         is KtParameter -> ResolverImpl.instance.evaluateConstant(psi.defaultValue, this.type)?.value
         is PsiAnnotationMethod -> JavaPsiFacade.getInstance(psi.project).constantEvaluationHelper.computeConstantExpression((psi).defaultValue)
-        else -> throw IllegalStateException()
+        else -> throw IllegalStateException("Unexpected psi ${psi.javaClass} $ExceptionMessage")
     }
 }

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSClassDeclarationDescriptorImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.binary
 
+import com.google.devtools.ksp.ExceptionMessage
 import org.jetbrains.kotlin.descriptors.*
 import com.google.devtools.ksp.symbol.*
 import com.google.devtools.ksp.symbol.impl.KSObjectCache
@@ -91,7 +92,7 @@ class KSClassDeclarationDescriptorImpl private constructor(val descriptor: Class
                     is PropertyDescriptor -> KSPropertyDeclarationDescriptorImpl.getCached(it)
                     is FunctionDescriptor -> KSFunctionDeclarationDescriptorImpl.getCached(it)
                     is ClassDescriptor -> getCached(it)
-                    else -> throw IllegalStateException()
+                    else -> throw IllegalStateException("Unexpected descriptor type ${it.javaClass} $ExceptionMessage")
                 }
             }
     }

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSFunctionDeclarationDescriptorImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.binary
 
+import com.google.devtools.ksp.ExceptionMessage
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.impl.AnonymousFunctionDescriptor
 import com.google.devtools.ksp.isOpen
@@ -31,6 +32,7 @@ import com.google.devtools.ksp.symbol.impl.toKSFunctionDeclaration
 import com.google.devtools.ksp.symbol.impl.toKSModifiers
 import org.jetbrains.kotlin.load.java.isFromJava
 import org.jetbrains.kotlin.resolve.OverridingUtil
+import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
 
 class KSFunctionDeclarationDescriptorImpl private constructor(val descriptor: FunctionDescriptor) : KSFunctionDeclaration,
     KSDeclarationDescriptorImpl(descriptor),
@@ -64,7 +66,7 @@ class KSFunctionDeclarationDescriptorImpl private constructor(val descriptor: Fu
             descriptor.dispatchReceiverParameter == null -> if (descriptor.isFromJava) FunctionKind.STATIC else FunctionKind.TOP_LEVEL
             !descriptor.name.isSpecial && !descriptor.name.asString().isEmpty() -> FunctionKind.MEMBER
             descriptor is AnonymousFunctionDescriptor -> FunctionKind.ANONYMOUS
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unable to resolve FunctionKind for ${descriptor.fqNameSafe} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSPropertySetterDescriptorImpl.kt

@@ -29,7 +29,8 @@ class KSPropertySetterDescriptorImpl private constructor(descriptor: PropertySet
     }
 
     override val parameter: KSValueParameter by lazy {
-        descriptor.valueParameters.singleOrNull()?.let { KSValueParameterDescriptorImpl.getCached(it) } ?: throw IllegalStateException()
+        descriptor.valueParameters.singleOrNull()?.let { KSValueParameterDescriptorImpl.getCached(it) }
+                ?: throw IllegalStateException("Failed to resolve property type")
     }
 
     override fun <D, R> accept(visitor: KSVisitor<D, R>, data: D): R {

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSTypeParameterDescriptorImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.binary
 
+import com.google.devtools.ksp.ExceptionMessage
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
@@ -47,7 +48,7 @@ class KSTypeParameterDescriptorImpl private constructor(val descriptor: TypePara
             is ClassDescriptor -> KSClassDeclarationDescriptorImpl.getCached(parent)
             is FunctionDescriptor -> KSFunctionDeclarationDescriptorImpl.getCached(parent)
             is PropertyDescriptor -> KSPropertyDeclarationDescriptorImpl.getCached(parent)
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected containing declaration for ${descriptor.fqNameSafe} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/binary/KSTypeReferenceDescriptorImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.binary
 
+import com.google.devtools.ksp.ExceptionMessage
 import org.jetbrains.kotlin.builtins.isSuspendFunctionTypeOrSubtype
 import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
@@ -44,10 +45,10 @@ class KSTypeReferenceDescriptorImpl private constructor(val kotlinType: KotlinTy
                 when (upperBound) {
                     is FlexibleType -> KSClassifierReferenceDescriptorImpl.getCached(upperBound.upperBound)
                     is SimpleType -> KSClassifierReferenceDescriptorImpl.getCached(upperBound)
-                    else -> throw IllegalStateException()
+                    else -> throw IllegalStateException("Unexpected upperbound type ${upperBound.javaClass} $ExceptionMessage")
                 }
             }
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected type: ${kotlinType.constructor.declarationDescriptor?.javaClass} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/java/KSTypeReferenceJavaImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.java
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.intellij.psi.*
 import com.intellij.psi.impl.source.PsiClassReferenceType
 import com.google.devtools.ksp.processing.impl.ResolverImpl
@@ -62,7 +63,7 @@ class KSTypeReferenceJavaImpl private constructor(val psi: PsiType) : KSTypeRefe
                 "char" -> ResolverImpl.instance.module.builtIns.charType
                 "boolean" -> ResolverImpl.instance.module.builtIns.booleanType
                 "void" -> ResolverImpl.instance.module.builtIns.unitType
-                else -> throw IllegalStateException()
+                else -> throw IllegalStateException("Unexpected primitive type ${this.name} $ExceptionMessage")
             }
         }
 
@@ -88,7 +89,7 @@ class KSTypeReferenceJavaImpl private constructor(val psi: PsiType) : KSTypeRefe
                 }
             }
             null -> KSClassifierReferenceDescriptorImpl.getCached((ResolverImpl.instance.builtIns.anyType as KSTypeImpl).kotlinType.makeNullable())
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected psi type for ${type.javaClass} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/kotlin/KSFunctionDeclarationImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.kotlin
 
+import com.google.devtools.ksp.ExceptionMessage
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import com.google.devtools.ksp.isOpen
 import com.google.devtools.ksp.isVisibleFrom
@@ -65,7 +66,7 @@ class KSFunctionDeclarationImpl private constructor(val ktFunction: KtFunction)
             when (ktFunction) {
                 is KtNamedFunction, is KtPrimaryConstructor, is KtSecondaryConstructor -> FunctionKind.MEMBER
                 is KtFunctionLiteral -> if (ktFunction.node.findChildByType(KtTokens.FUN_KEYWORD) != null) FunctionKind.ANONYMOUS else FunctionKind.LAMBDA
-                else -> throw IllegalStateException()
+                else -> throw IllegalStateException("Unexpected psi type ${ktFunction.javaClass} $ExceptionMessage")
             }
         }
     }

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/kotlin/KSPropertySetterImpl.kt

@@ -30,7 +30,7 @@ class KSPropertySetterImpl private constructor(ktPropertySetter: KtPropertyAcces
 
     override val parameter: KSValueParameter by lazy {
         ktPropertySetter.parameterList?.parameters?.singleOrNull()?.let { KSValueParameterImpl.getCached(it) }
-            ?: throw IllegalStateException()
+            ?: throw IllegalStateException("Failed to resolve property type")
     }
 
     override fun <D, R> accept(visitor: KSVisitor<D, R>, data: D): R {

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/kotlin/KSTypeParameterImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.kotlin
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.google.devtools.ksp.symbol.*
 import com.google.devtools.ksp.symbol.impl.KSObjectCache
 import com.google.devtools.ksp.symbol.impl.toKSModifiers
@@ -71,7 +72,7 @@ class KSTypeParameterImpl private constructor(val ktTypeParameter: KtTypeParamet
             is KtClassOrObject -> KSClassDeclarationImpl.getCached(owner)
             is KtFunction -> KSFunctionDeclarationImpl.getCached(owner)
             is KtProperty -> KSPropertyDeclarationImpl.getCached(owner)
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected containing declaration type ${owner.javaClass} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/kotlin/KSTypeReferenceImpl.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl.kotlin
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.google.devtools.ksp.processing.impl.ResolverImpl
 import com.google.devtools.ksp.symbol.*
 import com.google.devtools.ksp.symbol.impl.KSObjectCache
@@ -53,7 +54,7 @@ class KSTypeReferenceImpl private constructor(val ktTypeReference: KtTypeReferen
             is KtFunctionType -> KSCallableReferenceImpl.getCached(typeElement)
             is KtUserType -> KSClassifierReferenceImpl.getCached(typeElement)
             is KtDynamicType -> KSDynamicReferenceImpl.getCached(Unit)
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected type element ${typeElement?.javaClass} $ExceptionMessage")
         }
     }
 

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/synthetic/KSPropertySetterSyntheticImpl.kt

@@ -39,7 +39,8 @@ class KSPropertySetterSyntheticImpl(val ksPropertyDeclaration: KSPropertyDeclara
     }
 
     override val parameter: KSValueParameter by lazy {
-        descriptor.valueParameters.singleOrNull()?.let { KSValueParameterDescriptorImpl.getCached(it) } ?: throw IllegalStateException()
+        descriptor.valueParameters.singleOrNull()?.let { KSValueParameterDescriptorImpl.getCached(it) }
+                ?: throw IllegalStateException("Failed to resolve property type")
     }
 
     override fun <D, R> accept(visitor: KSVisitor<D, R>, data: D): R {

compiler-plugin/src/main/kotlin/com/google/devtools/ksp/symbol/impl/utils.kt

@@ -18,6 +18,7 @@
 
 package com.google.devtools.ksp.symbol.impl
 
+import com.google.devtools.ksp.ExceptionMessage
 import com.intellij.lang.jvm.JvmModifier
 import com.intellij.psi.*
 import org.jetbrains.kotlin.descriptors.*
@@ -209,7 +210,7 @@ fun KtClassOrObject.getClassType(): ClassKind {
             this.isAnnotation() -> ClassKind.ANNOTATION_CLASS
             else -> ClassKind.CLASS
         }
-        else -> throw IllegalStateException()
+        else -> throw IllegalStateException("Unexpected psi type ${this.javaClass} $ExceptionMessage")
     }
 }
 
@@ -228,7 +229,7 @@ fun org.jetbrains.kotlin.types.Variance.toKSVariance(): Variance {
         org.jetbrains.kotlin.types.Variance.IN_VARIANCE -> Variance.CONTRAVARIANT
         org.jetbrains.kotlin.types.Variance.OUT_VARIANCE -> Variance.COVARIANT
         org.jetbrains.kotlin.types.Variance.INVARIANT -> Variance.INVARIANT
-        else -> throw IllegalStateException()
+        else -> throw IllegalStateException("Unexpected variance value $this $ExceptionMessage")
     }
 }
 
@@ -246,7 +247,7 @@ internal fun KotlinType.replaceTypeArguments(newArguments: List<KSTypeArgument>)
         val type = when (ksTypeArgument) {
             is KSTypeArgumentKtImpl, is KSTypeArgumentJavaImpl, is KSTypeArgumentLiteImpl -> ksTypeArgument.type!!
             is KSTypeArgumentDescriptorImpl -> return@mapIndexed ksTypeArgument.descriptor
-            else -> throw IllegalStateException()
+            else -> throw IllegalStateException("Unexpected psi for type argument: ${ksTypeArgument.javaClass} $ExceptionMessage")
         }.toKotlinType()
 
         TypeProjectionImpl(variance, type)