From 9ec0ce6ec8ede71dfb489bfce515160d6651897f Mon Sep 17 00:00:00 2001
From: Simon Ogorodnik <Simon.Ogorodnik@jetbrains.com>
Date: Thu, 12 Jul 2018 17:08:33 +0300
Subject: [PATCH] KT-22815: Show documentation for function value/type params

---
 .../src/org/jetbrains/kotlin/idea/kdoc/findKDoc.kt   | 12 ++++++++----
 idea/testData/editor/quickDoc/AtFunctionParameter.kt |  5 ++++-
 idea/testData/editor/quickDoc/AtTypeParameter.kt     |  5 ++++-
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/idea/ide-common/src/org/jetbrains/kotlin/idea/kdoc/findKDoc.kt b/idea/ide-common/src/org/jetbrains/kotlin/idea/kdoc/findKDoc.kt
index 47ecc2b465e..cdc992f42f2 100644
--- a/idea/ide-common/src/org/jetbrains/kotlin/idea/kdoc/findKDoc.kt
+++ b/idea/ide-common/src/org/jetbrains/kotlin/idea/kdoc/findKDoc.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.idea.kdoc
 
 import com.intellij.psi.PsiElement
+import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorWithSource
@@ -62,13 +63,16 @@ fun KtElement.findKDoc(descriptorToPsi: (DeclarationDescriptorWithSource) -> Psi
     }
 
 
-    if (this is KtParameter) {
-        val classKDoc = containingClassOrObject?.getChildOfType<KDoc>()
+
+    if (this is KtParameter || this is KtTypeParameter) {
+        val containingDeclaration =
+            PsiTreeUtil.getParentOfType(this, KtDeclarationWithBody::class.java, KtClassOrObject::class.java, KtScript::class.java)
+        val classKDoc = containingDeclaration?.getChildOfType<KDoc>()
         val subjectName = name
         if (classKDoc != null && subjectName != null) {
             val propertySection =
-                classKDoc.findSectionByTag(KDocKnownTag.PROPERTY, subjectName)?.takeIf { this.isPropertyParameter() }
-                        ?: classKDoc.findDescendantOfType<KDocTag> { it.knownTag == KDocKnownTag.PARAM && it.getSubjectName() == subjectName }
+                classKDoc.findSectionByTag(KDocKnownTag.PROPERTY, subjectName)?.takeIf { this is KtParameter && this.isPropertyParameter() }
+                    ?: classKDoc.findDescendantOfType<KDocTag> { it.knownTag == KDocKnownTag.PARAM && it.getSubjectName() == subjectName }
             if (propertySection != null) {
                 return propertySection
             }
diff --git a/idea/testData/editor/quickDoc/AtFunctionParameter.kt b/idea/testData/editor/quickDoc/AtFunctionParameter.kt
index 17508ebbb5b..5062ba217c2 100644
--- a/idea/testData/editor/quickDoc/AtFunctionParameter.kt
+++ b/idea/testData/editor/quickDoc/AtFunctionParameter.kt
@@ -1,3 +1,6 @@
+/**
+ * @param f docs for param f
+ */
 fun some(<caret>f: (Int) -> String) : String? = null
 
-//INFO: <div class='definition'><pre>value-parameter <b>f</b>: (Int) &rarr; String</pre></div>
+//INFO: <div class='definition'><pre>value-parameter <b>f</b>: (Int) &rarr; String</pre></div><div class='content'><p>docs for param f</p></div><table class='sections'></table>
diff --git a/idea/testData/editor/quickDoc/AtTypeParameter.kt b/idea/testData/editor/quickDoc/AtTypeParameter.kt
index d61f28f4890..933b90acc26 100644
--- a/idea/testData/editor/quickDoc/AtTypeParameter.kt
+++ b/idea/testData/editor/quickDoc/AtTypeParameter.kt
@@ -1,5 +1,8 @@
 interface Base
 
+/**
+ * @param T this is docs for T
+ */
 class Some<<caret>T: Base>
 
-//INFO: <div class='definition'><pre><a href="psi_element://Some"><code>Some</code></a><br>&lt;<b>T</b> : <a href="psi_element://Base">Base</a>&gt;</pre></div>
+//INFO: <div class='definition'><pre><a href="psi_element://Some"><code>Some</code></a><br>&lt;<b>T</b> : <a href="psi_element://Base">Base</a>&gt;</pre></div><div class='content'><p>this is docs for T</p></div><table class='sections'></table>