[FE 1.0] Fix false-negative INVALID_IF_AS_EXPRESSION_WARNING and NO_E…

…LSE_IN_WHEN_WARNING ^KT-51711 Fixed
JetBrains · Apr 14, 2022 · 0c80614 · 0c80614
1 parent 26b4c94
commit 0c80614
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Showing 7 changed files with 63 additions and 8 deletions.
diff --git a/...vel/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java b/...vel/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java
diff --git a/...s/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java b/...s/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java
diff --git a/...rg/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java b/...rg/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java
diff --git a/compiler/frontend/cfg/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProviderImpl.kt b/compiler/frontend/cfg/src/org/jetbrains/kotlin/cfg/ControlFlowInformationProviderImpl.kt
@@ -955,20 +955,23 @@ class ControlFlowInformationProviderImpl private constructor(
         for (element in instruction.owner.getValueElements(value)) {
             if (element !is KtIfExpression) continue
 
-            if (element.isUsedAsExpression(trace.bindingContext)) {
-                val thenExpression = element.then
-                val elseExpression = element.`else`
+            val thenExpression = element.then
+            val elseExpression = element.`else`
+            val isEhxaustive = thenExpression != null && elseExpression != null
 
-                if (thenExpression == null || elseExpression == null) {
+            if (element.isUsedAsExpression(trace.bindingContext)) {
+                if (!isEhxaustive) {
                     trace.report(INVALID_IF_AS_EXPRESSION.on(element.ifKeyword))
                 } else {
                     checkImplicitCastOnConditionalExpression(element)
                 }
             } else if (!languageVersionSettings.supportsFeature(LanguageFeature.ProhibitNonExhaustiveIfInRhsOfElvis)) {
-                val parent = element.deparenthesizedParent
-                if (parent is KtBinaryExpression) {
-                    if (parent.operationToken === KtTokens.ELVIS) {
-                        trace.report(INVALID_IF_AS_EXPRESSION_WARNING.on(element.getIfKeyword()))
+                if (!isEhxaustive) {
+                    val parent = element.deparenthesizedParent
+                    if (parent is KtBinaryExpression) {
+                        if (parent.operationToken === KtTokens.ELVIS) {
+                            trace.report(INVALID_IF_AS_EXPRESSION_WARNING.on(element.getIfKeyword()))
+                        }
                     }
                 }
             }
@@ -1067,6 +1070,7 @@ class ControlFlowInformationProviderImpl private constructor(
                 if (
                     !usedAsExpression &&
                     missingCases.isNotEmpty() &&
+                    elseEntry == null &&
                     !languageVersionSettings.supportsFeature(LanguageFeature.ProhibitNonExhaustiveIfInRhsOfElvis)
                 ) {
                     val parent = element.deparenthesizedParent

diff --git a/compiler/testData/diagnostics/tests/controlStructures/kt51711.kt b/compiler/testData/diagnostics/tests/controlStructures/kt51711.kt
@@ -0,0 +1,22 @@
+// FIR_IDENTICAL
+// LANGUAGE: -ProhibitNonExhaustiveIfInRhsOfElvis
+// ISSUE: KT-51711
+// WITH_STDLIB
+
+private fun fake(a: String?) {}
+
+fun test_1(x: String?, y: String?) {
+    while (true) {
+        x ?: if (y == null) break else fake(y)
+    }
+}
+
+
+fun test_2(x: String?, y: String?) {
+    while (true) {
+        x ?: when {
+            true -> break
+            else -> y?.filter { it.isLowerCase() }
+        }
+    }
+}
diff --git a/compiler/testData/diagnostics/tests/controlStructures/kt51711.txt b/compiler/testData/diagnostics/tests/controlStructures/kt51711.txt
@@ -0,0 +1,5 @@
+package
+
+private fun fake(/*0*/ a: kotlin.String?): kotlin.Unit
+public fun test_1(/*0*/ x: kotlin.String?, /*1*/ y: kotlin.String?): kotlin.Unit
+public fun test_2(/*0*/ x: kotlin.String?, /*1*/ y: kotlin.String?): kotlin.Unit
diff --git a/...tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/...tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java