No parameter names in types for error messages

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/Renderers.kt

@@ -51,6 +51,7 @@ import org.jetbrains.kotlin.types.checker.KotlinTypeChecker
 import org.jetbrains.kotlin.utils.addToStdlib.firstIsInstanceOrNull
 import java.io.PrintWriter
 import java.io.StringWriter
+import java.lang.AssertionError
 
 object Renderers {
 
@@ -118,7 +119,7 @@ object Renderers {
 
     @JvmField val RENDER_CLASS_OR_OBJECT_NAME = Renderer<ClassDescriptor> { it.renderKindWithName() }
 
-    @JvmField val RENDER_TYPE = SmartTypeRenderer(DescriptorRenderer.FQ_NAMES_IN_TYPES)
+    @JvmField val RENDER_TYPE = SmartTypeRenderer(DescriptorRenderer.FQ_NAMES_IN_TYPES.withOptions { parameterNamesInFunctionalTypes = false })
 
     @JvmField val RENDER_POSITION_VARIANCE = Renderer {
         variance: Variance ->

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRenderer.kt

@@ -193,6 +193,7 @@ interface DescriptorRendererOptions {
     var renderConstructorKeyword: Boolean
     var renderUnabbreviatedType: Boolean
     var includeAdditionalModifiers: Boolean
+    var parameterNamesInFunctionalTypes: Boolean
 }
 
 object ExcludedTypeAnnotations {

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRendererImpl.kt

@@ -310,16 +310,16 @@ internal class DescriptorRendererImpl(
 
         append("(")
         val parameterTypes = getValueParameterTypesFromFunctionType(type)
-        val parameterNames = type.getParameterNamesFromFunctionType() ?: parameterTypes.map { SpecialNames.NO_NAME_PROVIDED }
-        assert(parameterNames.size == parameterTypes.size) { "Number of names does not match number of types for $type"}
+        val parameterNames = if (parameterNamesInFunctionalTypes) type.getParameterNamesFromFunctionType() else null
+        assert(parameterNames == null || parameterNames.size == parameterTypes.size) { "Number of names does not match number of types for $type"}
 
         for (index in parameterTypes.indices) {
             val typeProjection = parameterTypes[index]
-            val name = parameterNames[index]
+            val name = parameterNames?.get(index)
 
             if (index > 0) append(", ")
 
-            if (!name.isSpecial) {
+            if (name != null && !name.isSpecial) {
                 append(renderName(name))
                 append(": ")
             }

core/descriptors/src/org/jetbrains/kotlin/renderer/DescriptorRendererOptionsImpl.kt

@@ -18,6 +18,7 @@ package org.jetbrains.kotlin.renderer
 
 import org.jetbrains.kotlin.name.FqName
 import org.jetbrains.kotlin.types.KotlinType
+import java.lang.IllegalStateException
 import java.lang.reflect.Modifier
 import kotlin.jvm.internal.PropertyReference1Impl
 import kotlin.properties.Delegates
@@ -103,4 +104,6 @@ internal class DescriptorRendererOptionsImpl : DescriptorRendererOptions {
     override var renderUnabbreviatedType: Boolean by property(true)
 
     override var includeAdditionalModifiers: Boolean by property(true)
+
+    override var parameterNamesInFunctionalTypes: Boolean by property(true)
 }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/highlighter/IdeRenderers.kt

@@ -37,7 +37,7 @@ object IdeRenderers {
         descriptors.joinToString("") { "<li>${HTML.render(it, context)}</li>" }
     }
 
-    @JvmField val HTML_RENDER_TYPE = SmartTypeRenderer(DescriptorRenderer.HTML)
+    @JvmField val HTML_RENDER_TYPE = SmartTypeRenderer(DescriptorRenderer.HTML.withOptions { parameterNamesInFunctionalTypes = false })
 
     @JvmField val HTML_NONE_APPLICABLE_CALLS = Renderer {
         calls: Collection<ResolvedCall<*>> ->

idea/testData/diagnosticMessage/functionPlaceholder2.html

@@ -18,7 +18,7 @@ Type inference failed:
   <td style="white-space:nowrap;"></td>
   <td style="white-space:nowrap;"></td>
   <td style="white-space:nowrap;"><b>(</b></td>
-  <td align="right" style="white-space:nowrap;"><font color=red><b>(x: ???) &rarr; ???</b></font></td>
+  <td align="right" style="white-space:nowrap;"><font color=red><b>(???) &rarr; ???</b></font></td>
   <td style="white-space:nowrap;"><b>)</b></td>
 </tr>
 </table>

idea/testData/diagnosticMessage/typeMismatchWithFunctionalType.kt

@@ -0,0 +1,9 @@
+// !DIAGNOSTICS_NUMBER: 1
+// !DIAGNOSTICS: TYPE_MISMATCH
+// !MESSAGE_TYPE: TEXT
+
+fun foo(handler: (s: String) -> Unit) {
+    bar(handler)
+}
+
+fun bar(a: (n: Int) -> Unit) {}

idea/testData/diagnosticMessage/typeMismatchWithFunctionalType1.txt

@@ -0,0 +1,2 @@
+<!-- typeMismatchWithFunctionalType1 -->
+Type mismatch: inferred type is (String) -> Unit but (Int) -> Unit was expected

idea/testData/quickfix/createFromUsage/createFunction/call/kt10983.kt

@@ -9,8 +9,8 @@
 // ACTION: Rename reference
 // ERROR: A 'return' expression required in a function with a block body ('{...}')
 // ERROR: The expression cannot be a selector (occur after a dot)
-// ERROR: Type inference failed: inline fun <T> Iterable<T>.firstOrNull(predicate: (T) -> Boolean): T?<br>cannot be applied to<br>receiver: Collection<List<String>>  arguments: ((group: List<String>) -> () -> Boolean)<br>
-// ERROR: Type mismatch: inferred type is (group: List<String>) -> () -> Boolean but (List<String>) -> Boolean was expected
+// ERROR: Type inference failed: inline fun <T> Iterable<T>.firstOrNull(predicate: (T) -> Boolean): T?<br>cannot be applied to<br>receiver: Collection<List<String>>  arguments: ((List<String>) -> () -> Boolean)<br>
+// ERROR: Type mismatch: inferred type is (List<String>) -> () -> Boolean but (List<String>) -> Boolean was expected
 // ERROR: Unresolved reference: maximumSizeOfGroup
 
 fun doSomethingStrangeWithCollection(collection: Collection<String>): Collection<String>? {

idea/testData/quickfix/typeMismatch/typeMismatchOnReturnedExpression/dontChangeFunctionReturnTypeToErrorType.kt

@@ -6,7 +6,7 @@
 // ACTION: Create type alias 'NoSuchType'
 // ACTION: Remove explicit lambda parameter types (may break code)
 // ACTION: Create type parameter 'NoSuchType' in function 'foo'
-// ERROR: Type mismatch: inferred type is (x: [ERROR : NoSuchType]) -> Int but Int was expected
+// ERROR: Type mismatch: inferred type is ([ERROR : NoSuchType]) -> Int but Int was expected
 // ERROR: Unresolved reference: NoSuchType
 
 fun foo(): Int {

idea/tests/org/jetbrains/kotlin/idea/highlighter/DiagnosticMessageTestGenerated.java

@@ -251,6 +251,12 @@ public class DiagnosticMessageTestGenerated extends AbstractDiagnosticMessageTes
         doTest(fileName);
     }
 
+    @TestMetadata("typeMismatchWithFunctionalType.kt")
+    public void testTypeMismatchWithFunctionalType() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/diagnosticMessage/typeMismatchWithFunctionalType.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("typeMismatchWithNothing.kt")
     public void testTypeMismatchWithNothing() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/diagnosticMessage/typeMismatchWithNothing.kt");