From f5c59b1343ff1c21cfee958b46b29ef0526cadaf Mon Sep 17 00:00:00 2001
From: Dmitry Petrov <dmitry.petrov@jetbrains.com>
Date: Fri, 21 Oct 2016 15:09:52 +0300
Subject: [PATCH] [NI] Report special error message on constant expression type
 mismatch.

---
 .../DiagnosticReporterByTrackingStrategy.kt   | 19 +++++++++++++++++++
 .../tower/KotlinToResolvedCallTransformer.kt  | 10 +++++++---
 2 files changed, 26 insertions(+), 3 deletions(-)

diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/DiagnosticReporterByTrackingStrategy.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/DiagnosticReporterByTrackingStrategy.kt
index 00a8c2f6739..641a2506be5 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/DiagnosticReporterByTrackingStrategy.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/DiagnosticReporterByTrackingStrategy.kt
@@ -21,6 +21,8 @@ import org.jetbrains.kotlin.diagnostics.Errors
 import org.jetbrains.kotlin.diagnostics.Errors.*
 import org.jetbrains.kotlin.diagnostics.Errors.BadNamedArgumentsTarget.*
 import org.jetbrains.kotlin.psi.Call
+import org.jetbrains.kotlin.psi.KtConstantExpression
+import org.jetbrains.kotlin.psi.KtExpression
 import org.jetbrains.kotlin.psi.KtPsiUtil
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.BindingTrace
@@ -32,9 +34,13 @@ import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowValueFactory
 import org.jetbrains.kotlin.resolve.calls.smartcasts.SmartCastManager
 import org.jetbrains.kotlin.resolve.calls.tasks.TracingStrategy
 import org.jetbrains.kotlin.resolve.calls.tower.*
+import org.jetbrains.kotlin.resolve.constants.CompileTimeConstantChecker
+import org.jetbrains.kotlin.resolve.constants.evaluate.ConstantExpressionEvaluator
+import org.jetbrains.kotlin.resolve.descriptorUtil.builtIns
 import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver
 
 class DiagnosticReporterByTrackingStrategy(
+        val constantExpressionEvaluator: ConstantExpressionEvaluator,
         val context: BasicCallResolutionContext,
         val trace: BindingTrace,
         val psiKotlinCall: PSIKotlinCall
@@ -137,6 +143,7 @@ class DiagnosticReporterByTrackingStrategy(
                 val constraintError = diagnostic as NewConstraintError
                 (constraintError.position as? ArgumentConstraintPosition)?.let {
                     val expression = it.argument.psiExpression ?: return
+                    if (reportConstantTypeMismatch(constraintError, expression)) return
                     trace.report(Errors.TYPE_MISMATCH.on(expression, constraintError.upperType, constraintError.lowerType))
                 }
                 (constraintError.position as? ExplicitTypeParameterConstraintPosition)?.let {
@@ -153,4 +160,16 @@ class DiagnosticReporterByTrackingStrategy(
             }
         }
     }
+
+    private fun reportConstantTypeMismatch(constraintError: NewConstraintError, expression: KtExpression): Boolean {
+        if (expression is KtConstantExpression) {
+            val builtIns = context.scope.ownerDescriptor.builtIns
+            val constantValue = constantExpressionEvaluator.evaluateToConstantValue(expression, trace, context.expectedType)
+            val hasConstantTypeError = CompileTimeConstantChecker(context, builtIns, true)
+                    .checkConstantExpressionType(constantValue, expression, constraintError.upperType)
+            if (hasConstantTypeError) return true
+        }
+        return false
+    }
+
 }
\ No newline at end of file
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinToResolvedCallTransformer.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinToResolvedCallTransformer.kt
index bc3b912c9bc..45884d144cb 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinToResolvedCallTransformer.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tower/KotlinToResolvedCallTransformer.kt
@@ -25,7 +25,9 @@ import org.jetbrains.kotlin.psi.KtPsiUtil
 import org.jetbrains.kotlin.psi.ValueArgument
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.BindingTrace
-import org.jetbrains.kotlin.resolve.calls.*
+import org.jetbrains.kotlin.resolve.calls.ArgumentTypeResolver
+import org.jetbrains.kotlin.resolve.calls.DiagnosticReporterByTrackingStrategy
+import org.jetbrains.kotlin.resolve.calls.REPORT_MISSING_NEW_INFERENCE_DIAGNOSTIC
 import org.jetbrains.kotlin.resolve.calls.callResolverUtil.getEffectiveExpectedType
 import org.jetbrains.kotlin.resolve.calls.callUtil.isFakeElement
 import org.jetbrains.kotlin.resolve.calls.checkers.CallChecker
@@ -36,6 +38,7 @@ import org.jetbrains.kotlin.resolve.calls.model.*
 import org.jetbrains.kotlin.resolve.calls.results.ResolutionStatus
 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowInfo
 import org.jetbrains.kotlin.resolve.calls.tasks.ExplicitReceiverKind
+import org.jetbrains.kotlin.resolve.constants.evaluate.ConstantExpressionEvaluator
 import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeUtils
@@ -49,7 +52,8 @@ class KotlinToResolvedCallTransformer(
         private val callCheckers: Iterable<CallChecker>,
         private val languageFeatureSettings: LanguageVersionSettings,
         private val dataFlowAnalyzer: DataFlowAnalyzer,
-        private val argumentTypeResolver: ArgumentTypeResolver
+        private val argumentTypeResolver: ArgumentTypeResolver,
+        private val constantExpressionEvaluator: ConstantExpressionEvaluator
 ) {
 
     fun <D : CallableDescriptor> transformAndReport(
@@ -185,7 +189,7 @@ class KotlinToResolvedCallTransformer(
                 reported = true
             }
         }
-        val diagnosticReporter = DiagnosticReporterByTrackingStrategy(context, reportTrackedTrace, completedCall.kotlinCall.psiKotlinCall)
+        val diagnosticReporter = DiagnosticReporterByTrackingStrategy(constantExpressionEvaluator, context, reportTrackedTrace, completedCall.kotlinCall.psiKotlinCall)
 
         for (diagnostic in completedCall.resolutionStatus.diagnostics) {
             reported = false