Support definitely non-nullable types (#2520)

* Support definitely non-nullable types

[Definitely non-nullable types](https://github.com/Kotlin/KEEP/blob/c72601cf35c1e95a541bb4b230edb474a6d1d1a8/proposals/definitely-non-nullable-types.md) are enabled since Kotlin 1.7

4 files changed, 11 insertions, 1 deletions

diff --git a/plugins/base/src/main/kotlin/signatures/KotlinSignatureProvider.kt b/plugins/base/src/main/kotlin/signatures/KotlinSignatureProvider.kt
index 294c1d24..02da3f24 100644
--- a/plugins/base/src/main/kotlin/signatures/KotlinSignatureProvider.kt
+++ b/plugins/base/src/main/kotlin/signatures/KotlinSignatureProvider.kt
@@ -430,6 +430,11 @@ class KotlinSignatureProvider(ctcc: CommentsToContentConverter, logger: DokkaLog
                 signatureForProjection(p.inner, showFullyQualifiedName)
                 operator("?")
             }
+            is DefinitelyNonNullable -> group(styles = emptySet()) {
+                signatureForProjection(p.inner, showFullyQualifiedName)
+                operator(" & ")
+                link("Any", DriOfAny)
+            }
 
             is TypeAliased -> signatureForProjection(p.typeAlias)
             is JavaObject -> {
diff --git a/plugins/base/src/main/kotlin/signatures/KotlinSignatureUtils.kt b/plugins/base/src/main/kotlin/signatures/KotlinSignatureUtils.kt
index 0fea9132..381fadf1 100644
--- a/plugins/base/src/main/kotlin/signatures/KotlinSignatureUtils.kt
+++ b/plugins/base/src/main/kotlin/signatures/KotlinSignatureUtils.kt
@@ -39,6 +39,7 @@ object KotlinSignatureUtils : JvmSignatureUtils {
                 is TypeParameter -> dri
                 is TypeConstructor -> dri
                 is Nullable -> inner.driOrNull
+                is DefinitelyNonNullable -> inner.driOrNull
                 is PrimitiveJavaType -> dri
                 is Void -> DriOfUnit
                 is JavaObject -> DriOfAny
@@ -52,6 +53,7 @@ object KotlinSignatureUtils : JvmSignatureUtils {
         is TypeParameter -> listOf(dri)
         is TypeConstructor -> listOf(dri) + projections.flatMap { it.drisOfAllNestedBounds }
         is Nullable -> inner.drisOfAllNestedBounds
+        is DefinitelyNonNullable -> inner.drisOfAllNestedBounds
         is PrimitiveJavaType -> listOf(dri)
         is Void -> listOf(DriOfUnit)
         is JavaObject -> listOf(DriOfAny)
diff --git a/plugins/base/src/main/kotlin/transformers/documentables/ExtensionExtractorTransformer.kt b/plugins/base/src/main/kotlin/transformers/documentables/ExtensionExtractorTransformer.kt
index 2a8baf0b..73023a86 100644
--- a/plugins/base/src/main/kotlin/transformers/documentables/ExtensionExtractorTransformer.kt
+++ b/plugins/base/src/main/kotlin/transformers/documentables/ExtensionExtractorTransformer.kt
@@ -9,7 +9,6 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
 import kotlinx.coroutines.flow.toList
-import org.jetbrains.dokka.base.signatures.KotlinSignatureUtils.driOrNull
 import org.jetbrains.dokka.links.DRI
 import org.jetbrains.dokka.links.DriOfAny
 import org.jetbrains.dokka.model.*
@@ -91,6 +90,7 @@ private fun Callable.asPairsWithReceiverDRIs(): Sequence<Pair<DRI, Callable>> =
 // care about it since there is nowhere to put documentation of given extension.
 private fun Callable.findReceiverDRIs(bound: Bound): Sequence<DRI> = when (bound) {
     is Nullable -> findReceiverDRIs(bound.inner)
+    is DefinitelyNonNullable -> findReceiverDRIs(bound.inner)
     is TypeParameter ->
         if (this is DFunction && bound.dri == this.dri)
             generics.find { it.name == bound.name }?.bounds?.asSequence()?.flatMap(::findReceiverDRIs).orEmpty()
diff --git a/plugins/base/src/main/kotlin/translators/descriptors/DefaultDescriptorToDocumentableTranslator.kt b/plugins/base/src/main/kotlin/translators/descriptors/DefaultDescriptorToDocumentableTranslator.kt
index 6c4d7a0d..bfd755cd 100644
--- a/plugins/base/src/main/kotlin/translators/descriptors/DefaultDescriptorToDocumentableTranslator.kt
+++ b/plugins/base/src/main/kotlin/translators/descriptors/DefaultDescriptorToDocumentableTranslator.kt
@@ -910,6 +910,9 @@ private class DokkaDescriptorVisitor(
                 expandedType.toBound(),
                 annotations()
             )
+            is DefinitelyNotNullType -> DefinitelyNonNullable(
+                original.toBound()
+            )
             else -> when (val ctor = constructor.declarationDescriptor) {
                 is TypeParameterDescriptor -> TypeParameter(
                     dri = DRI.from(ctor),