From 108e97b70e66c30d90db8328917c2eaac8d8cc4c Mon Sep 17 00:00:00 2001
From: Dmitry Jemerov <yole@jetbrains.com>
Date: Sat, 22 Apr 2017 12:43:35 +0200
Subject: [PATCH] Show parameter hints for ambiguous calls

---
 .../KotlinInlayParameterHintsProvider.kt      | 38 ++++++++++++------
 .../parameterInfo/InlayParameterHintsTest.kt  | 39 +++++++++++++++++++
 2 files changed, 66 insertions(+), 11 deletions(-)

diff --git a/idea/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinInlayParameterHintsProvider.kt b/idea/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinInlayParameterHintsProvider.kt
index 1346be715ad..63680889c60 100644
--- a/idea/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinInlayParameterHintsProvider.kt
+++ b/idea/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinInlayParameterHintsProvider.kt
@@ -24,11 +24,14 @@ import com.intellij.lang.Language
 import com.intellij.lang.java.JavaLanguage
 import com.intellij.psi.PsiElement
 import com.intellij.psi.codeStyle.CodeStyleSettingsManager
+import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ConstructorDescriptor
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
 import org.jetbrains.kotlin.idea.core.formatter.KotlinCodeStyleSettings
+import org.jetbrains.kotlin.idea.core.resolveCandidates
 import org.jetbrains.kotlin.idea.intentions.SpecifyTypeExplicitlyIntention
 import org.jetbrains.kotlin.idea.quickfix.createFromUsage.callableBuilder.getReturnTypeReference
 import org.jetbrains.kotlin.lexer.KtTokens
@@ -38,8 +41,10 @@ import org.jetbrains.kotlin.psi.psiUtil.endOffset
 import org.jetbrains.kotlin.psi.psiUtil.startOffset
 import org.jetbrains.kotlin.renderer.DescriptorRenderer
 import org.jetbrains.kotlin.renderer.RenderingFormat
+import org.jetbrains.kotlin.resolve.calls.callUtil.getCall
 import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 import org.jetbrains.kotlin.resolve.calls.model.DefaultValueArgument
+import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameOrNull
 import org.jetbrains.kotlin.resolve.descriptorUtil.fqNameSafe
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
@@ -121,21 +126,32 @@ private enum class HintType(desc: String, enabled: Boolean) {
 
         private fun provideParameterInfo(element: KtCallExpression): List<InlayInfo> {
             val ctx = element.analyze(BodyResolveMode.PARTIAL)
-            element.getResolvedCall(ctx)?.let { resolvedCall ->
-                return resolvedCall.valueArguments.mapNotNull { (valueParam: ValueParameterDescriptor, resolvedArg) ->
-                    resolvedArg.arguments.firstOrNull()?.let { arg ->
-                        arg.getArgumentExpression()?.let { argExp ->
-                            if (!arg.isNamed() && !valueParam.name.isSpecial && argExp.isUnclearExpression()) {
-                                val prefix = if (valueParam.varargElementType != null) "..." else ""
-                                return@mapNotNull InlayInfo(prefix + valueParam.name.identifier, argExp.startOffset)
-                            }
+            val call = element.getCall(ctx) ?: return emptyList()
+            val candidates = call.resolveCandidates(ctx, element.getResolutionFacade())
+            if (candidates.isEmpty()) return emptyList()
+            candidates.singleOrNull()?.let { return getParameterInfoForCallCandidate(it) }
+            return candidates.map { getParameterInfoForCallCandidate(it) }.reduce { infos1, infos2 ->
+                for (index in infos1.indices) {
+                    if (index >= infos2.size || infos1[index] != infos2[index]) {
+                        return@reduce infos1.subList(0, index)
+                    }
+                }
+                infos1
+            }
+        }
+
+        private fun getParameterInfoForCallCandidate(resolvedCall: ResolvedCall<out CallableDescriptor>): List<InlayInfo> {
+            return resolvedCall.valueArguments.mapNotNull { (valueParam: ValueParameterDescriptor, resolvedArg) ->
+                resolvedArg.arguments.firstOrNull()?.let { arg ->
+                    arg.getArgumentExpression()?.let { argExp ->
+                        if (!arg.isNamed() && !valueParam.name.isSpecial && argExp.isUnclearExpression()) {
+                            val prefix = if (valueParam.varargElementType != null) "..." else ""
+                            return@mapNotNull InlayInfo(prefix + valueParam.name.identifier, argExp.startOffset)
                         }
                     }
-                    null
                 }
+                null
             }
-
-            return emptyList()
         }
 
         private fun KtExpression.isUnclearExpression() = when(this) {
diff --git a/idea/tests/org/jetbrains/kotlin/idea/parameterInfo/InlayParameterHintsTest.kt b/idea/tests/org/jetbrains/kotlin/idea/parameterInfo/InlayParameterHintsTest.kt
index 5735cb27e2b..dd9deb3de5f 100644
--- a/idea/tests/org/jetbrains/kotlin/idea/parameterInfo/InlayParameterHintsTest.kt
+++ b/idea/tests/org/jetbrains/kotlin/idea/parameterInfo/InlayParameterHintsTest.kt
@@ -91,5 +91,44 @@ class InlayParameterHintsTest : KotlinLightCodeInsightFixtureTestCase() {
 """)
     }
 
+    fun `test inline positive and negative numbers`() {
+        check("""
+  fun main() {
+    val obj = Any()
+    count(<hint text="test:"/>-1, obj);
+    count(<hint text="test:"/>+1, obj);
+  }
+
+  fun count(test: Int, obj: Any) {
+  }
+}
+""")
+    }
+
+    fun `test show ambiguous`() {
+        check("""
+  fun main() {
+    test(<hint text="a:"/>10, x);
+  }
+  fun test(a: Int, bS: String) {}
+  fun test(a: Int, bI: Int) {}
+""")
+    }
+
+    fun `test show ambiguous constructor`() {
+        check("""
+  fun main() {
+    X(<hint text="a:"/>10, x);
+  }
+}
+
+class X {
+  constructor(a: Int, bI: Int) {}
+  constructor(a: Int, bS: String) {}
+}
+""")
+    }
+
+
 
 }