4 files changed, 76 insertions, 1 deletions
diff --git a/src/Formats/StructuredFormatService.kt b/src/Formats/StructuredFormatService.kt
index 41deeed0..b3d1463e 100644
--- a/src/Formats/StructuredFormatService.kt
+++ b/src/Formats/StructuredFormatService.kt
@@ -114,6 +114,9 @@ public abstract class StructuredFormatService(locationService: LocationService,
             }
             // All items have exactly the same documentation, so we can use any item to render it
             val item = items.first()
+            item.details(DocumentationNode.Kind.OverloadGroupNote).forEach {
+                to.append(formatText(location, it.content))
+            }
             to.append(formatText(location, item.content.summary))
             appendDescription(location, to, item)
             appendLine(to)
diff --git a/src/Kotlin/DocumentationBuilder.kt b/src/Kotlin/DocumentationBuilder.kt
index 14ba94be..2c4c5119 100644
--- a/src/Kotlin/DocumentationBuilder.kt
+++ b/src/Kotlin/DocumentationBuilder.kt
@@ -12,7 +12,9 @@ import org.jetbrains.kotlin.idea.kdoc.KDocFinder
 import org.jetbrains.kotlin.idea.kdoc.resolveKDocLink
 import org.jetbrains.kotlin.kdoc.psi.impl.KDocSection
 import org.jetbrains.kotlin.kdoc.psi.impl.KDocTag
+import org.jetbrains.kotlin.lexer.JetSingleValueToken
 import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.psi.JetParameter
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.constants.CompileTimeConstant
@@ -21,7 +23,7 @@ import org.jetbrains.kotlin.resolve.source.getPsi
 import org.jetbrains.kotlin.types.ErrorUtils
 import org.jetbrains.kotlin.types.JetType
 import org.jetbrains.kotlin.types.TypeProjection
-import org.jetbrains.kotlin.types.Variance
+import org.jetbrains.kotlin.types.expressions.OperatorConventions
 
 public data class DocumentationOptions(val includeNonPublic: Boolean = false,
                                        val sourceLinks: List<SourceLinkDefinition>)
@@ -394,6 +396,7 @@ class DocumentationBuilder(val session: ResolveSession,
         node.appendType(getReturnType())
         node.appendAnnotations(this)
         node.appendSourceLink(getSource())
+        node.appendOperatorOverloadNote(this)
 
         getOverriddenDescriptors().forEach {
             addOverrideLink(it, this)
@@ -414,6 +417,58 @@ class DocumentationBuilder(val session: ResolveSession,
         }
     }
 
+    fun DocumentationNode.appendOperatorOverloadNote(descriptor: FunctionDescriptor) {
+        val operatorName = descriptor.getImplementedOperator()
+        if (operatorName != null) {
+            val content = Content()
+            content.append(ContentText("Implements "))
+            content.strong {
+                text("operator ")
+                code {
+                    text(operatorName)
+                }
+            }
+            val noteNode = DocumentationNode("", content, DocumentationNode.Kind.OverloadGroupNote)
+            append(noteNode, DocumentationReference.Kind.Detail)
+        }
+    }
+
+    fun FunctionDescriptor.getImplementedOperator(): String? {
+        var arity = getValueParameters().size()
+        if (getContainingDeclaration() is ClassDescriptor) {
+            arity++
+        }
+        if (getExtensionReceiverParameter() != null) {
+            arity++
+        }
+
+        val token = if (arity == 2) {
+            OperatorConventions.BINARY_OPERATION_NAMES.inverse().get(getName()) ?:
+            OperatorConventions.ASSIGNMENT_OPERATIONS.inverse().get(getName()) ?:
+            OperatorConventions.BOOLEAN_OPERATIONS.inverse().get(getName())
+        } else if (arity == 1) {
+            OperatorConventions.UNARY_OPERATION_NAMES.inverse().get(getName())
+        }
+        else null
+
+        if (token is JetSingleValueToken) {
+            return token.getValue()
+        }
+
+        val name = getName().asString()
+        if (arity == 2 && name == "contains") {
+            return "in"
+        }
+        if (arity >= 2 && (name == "get" || name == "set")) {
+            return "[]"
+        }
+        if (arity == 2 && name == "equals" && getValueParameters().size() == 1 &&
+            KotlinBuiltIns.isNullableAny(getValueParameters().first().getType())) {
+            return "=="
+        }
+        return null
+    }
+
     fun PropertyDescriptor.build(): DocumentationNode {
         val node = DocumentationNode(this, if (inClassObject()) Kind.DefaultObjectProperty else Kind.Property)
         node.appendInPageChildren(getTypeParameters(), DocumentationReference.Kind.Detail)
diff --git a/src/Model/Content.kt b/src/Model/Content.kt
index d343c648..91a7da81 100644
--- a/src/Model/Content.kt
+++ b/src/Model/Content.kt
@@ -98,6 +98,17 @@ fun ContentBlock.keyword(value: String) = append(ContentKeyword(value))
 fun ContentBlock.symbol(value: String) = append(ContentSymbol(value))
 fun ContentBlock.identifier(value: String, kind: IdentifierKind = IdentifierKind.Other) = append(ContentIdentifier(value, kind))
 fun ContentBlock.nbsp() = append(ContentNonBreakingSpace)
+fun ContentBlock.strong(body: ContentBlock.() -> Unit) {
+    val strong = ContentStrong()
+    strong.body()
+    append(strong)
+}
+
+fun ContentBlock.code(body: ContentBlock.() -> Unit) {
+    val code = ContentCode()
+    code.body()
+    append(code)
+}
 
 fun ContentBlock.link(to: DocumentationNode, body: ContentBlock.() -> Unit) {
     val block = ContentNodeDirectLink(to)
diff --git a/src/Model/DocumentationNode.kt b/src/Model/DocumentationNode.kt
index c9373849..663ca021 100644
--- a/src/Model/DocumentationNode.kt
+++ b/src/Model/DocumentationNode.kt
@@ -101,6 +101,12 @@ public open class DocumentationNode(val name: String,
         Value
 
         SourceUrl
+
+        /**
+         * A note which is rendered once on a page documenting a group of overloaded functions.
+         * Needs to be generated equally on all overloads.
+         */
+        OverloadGroupNote
     }
 
 }