[FE] Fix positioning strategy for SAFE_CALL_WILL_CHANGE_NULLABILITY warning

^KT-46860

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java

@@ -21176,6 +21176,12 @@ public class DiagnosisCompilerTestFE10TestdataTestGenerated extends AbstractDiag
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/safeAccessOnUnit.kt");
             }
 
+            @Test
+            @TestMetadata("safeCallOnNotNullableType.kt")
+            public void testSafeCallOnNotNullableType() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.kt");
+            }
+
             @Test
             @TestMetadata("safeCallOnTypeWithNullableUpperBound.kt")
             public void testSafeCallOnTypeWithNullableUpperBound() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java

@@ -21176,6 +21176,12 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/safeAccessOnUnit.kt");
             }
 
+            @Test
+            @TestMetadata("safeCallOnNotNullableType.kt")
+            public void testSafeCallOnNotNullableType() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.kt");
+            }
+
             @Test
             @TestMetadata("safeCallOnTypeWithNullableUpperBound.kt")
             public void testSafeCallOnTypeWithNullableUpperBound() throws Exception {

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java

@@ -21176,6 +21176,12 @@ public class FirOldFrontendDiagnosticsWithLightTreeTestGenerated extends Abstrac
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/safeAccessOnUnit.kt");
             }
 
+            @Test
+            @TestMetadata("safeCallOnNotNullableType.kt")
+            public void testSafeCallOnNotNullableType() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.kt");
+            }
+
             @Test
             @TestMetadata("safeCallOnTypeWithNullableUpperBound.kt")
             public void testSafeCallOnTypeWithNullableUpperBound() throws Exception {

compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt

@@ -1113,7 +1113,7 @@ object DIAGNOSTICS_LIST : DiagnosticList("FirErrors") {
         val UNNECESSARY_SAFE_CALL by warning<PsiElement>(PositioningStrategy.SAFE_ACCESS) {
             parameter<ConeKotlinType>("receiverType")
         }
-        val SAFE_CALL_WILL_CHANGE_NULLABILITY by warning<KtSafeQualifiedExpression>()
+        val SAFE_CALL_WILL_CHANGE_NULLABILITY by warning<KtSafeQualifiedExpression>(PositioningStrategy.CALL_ELEMENT_WITH_DOT)
         val UNEXPECTED_SAFE_CALL by error<PsiElement>(PositioningStrategy.SAFE_ACCESS)
         val UNNECESSARY_NOT_NULL_ASSERTION by warning<KtExpression>(PositioningStrategy.OPERATOR) {
             parameter<ConeKotlinType>("receiverType")

compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/model/RegularDiagnosticData.kt

@@ -113,7 +113,7 @@ enum class PositioningStrategy(private val strategy: String? = null) {
     DECLARATION_START_TO_NAME,
     REDUNDANT_NULLABLE,
     INLINE_FUN_MODIFIER,
-
+    CALL_ELEMENT_WITH_DOT,
     ;
 
     val expressionToCreate get() = "SourceElementPositioningStrategies.${strategy ?: name}"

compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt

@@ -592,7 +592,7 @@ object FirErrors {
     val UNSAFE_OPERATOR_CALL by error3<KtExpression, FirExpression, String, FirExpression>(SourceElementPositioningStrategies.REFERENCE_BY_QUALIFIED)
     val ITERATOR_ON_NULLABLE by error0<KtExpression>()
     val UNNECESSARY_SAFE_CALL by warning1<PsiElement, ConeKotlinType>(SourceElementPositioningStrategies.SAFE_ACCESS)
-    val SAFE_CALL_WILL_CHANGE_NULLABILITY by warning0<KtSafeQualifiedExpression>()
+    val SAFE_CALL_WILL_CHANGE_NULLABILITY by warning0<KtSafeQualifiedExpression>(SourceElementPositioningStrategies.CALL_ELEMENT_WITH_DOT)
     val UNEXPECTED_SAFE_CALL by error0<PsiElement>(SourceElementPositioningStrategies.SAFE_ACCESS)
     val UNNECESSARY_NOT_NULL_ASSERTION by warning1<KtExpression, ConeKotlinType>(SourceElementPositioningStrategies.OPERATOR)
     val NOT_NULL_ASSERTION_ON_LAMBDA_EXPRESSION by warning0<KtExpression>(SourceElementPositioningStrategies.OPERATOR)

compiler/frontend.common-psi/src/org/jetbrains/kotlin/diagnostics/LightTreePositioningStrategies.kt

@@ -1120,6 +1120,30 @@ object LightTreePositioningStrategies {
             return markElement(byKeyword, startOffset, endOffset, tree, node)
         }
     }
+
+    val CALL_ELEMENT_WITH_DOT: LightTreePositioningStrategy = object : LightTreePositioningStrategy() {
+        override fun mark(
+            node: LighterASTNode,
+            startOffset: Int,
+            endOffset: Int,
+            tree: FlyweightCapableTreeStructure<LighterASTNode>
+        ): List<TextRange> {
+            val callElementRanges = SELECTOR_BY_QUALIFIED.mark(node, startOffset, endOffset, tree)
+            val callElementRange = when (callElementRanges.size) {
+                1 -> callElementRanges.first()
+                else -> return callElementRanges
+            }
+
+            val dotRanges = SAFE_ACCESS.mark(node, startOffset, endOffset, tree)
+            val dotRange = when (dotRanges.size) {
+                1 -> dotRanges.first()
+                else -> return dotRanges
+            }
+
+            return listOf(TextRange(dotRange.startOffset, callElementRange.endOffset))
+        }
+    }
+
 }
 
 fun KtSourceElement.hasValOrVar(): Boolean =

compiler/frontend.common-psi/src/org/jetbrains/kotlin/diagnostics/PositioningStrategies.kt

@@ -499,6 +499,25 @@ object PositioningStrategies {
         }
     }
 
+    @JvmField
+    val CALL_ELEMENT_WITH_DOT: PositioningStrategy<KtQualifiedExpression> = object : PositioningStrategy<KtQualifiedExpression>() {
+        override fun mark(element: KtQualifiedExpression): List<TextRange> {
+            val callElementRanges = SELECTOR_BY_QUALIFIED.mark(element)
+            val callElementRange = when (callElementRanges.size) {
+                1 -> callElementRanges.first()
+                else -> return callElementRanges
+            }
+
+            val dotRanges = SAFE_ACCESS.mark(element)
+            val dotRange = when (dotRanges.size) {
+                1 -> dotRanges.first()
+                else -> return dotRanges
+            }
+
+            return listOf(TextRange(dotRange.startOffset, callElementRange.endOffset))
+        }
+    }
+
     @JvmField
     val DECLARATION_WITH_BODY: PositioningStrategy<KtDeclarationWithBody> = object : PositioningStrategy<KtDeclarationWithBody>() {
         override fun mark(element: KtDeclarationWithBody): List<TextRange> {

compiler/frontend.common-psi/src/org/jetbrains/kotlin/diagnostics/SourceElementPositioningStrategies.kt

@@ -364,4 +364,9 @@ object SourceElementPositioningStrategies {
         LightTreePositioningStrategies.DELEGATED_SUPERTYPE_BY_KEYWORD,
         PositioningStrategies.DELEGATED_SUPERTYPE_BY_KEYWORD
     )
+
+    val CALL_ELEMENT_WITH_DOT = SourceElementPositioningStrategy(
+        LightTreePositioningStrategies.CALL_ELEMENT_WITH_DOT,
+        PositioningStrategies.CALL_ELEMENT_WITH_DOT
+    )
 }

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -1097,7 +1097,7 @@ public interface Errors {
     DiagnosticFactory3<KtExpression, PsiElement, String, PsiElement> UNSAFE_INFIX_CALL = DiagnosticFactory3.create(ERROR);
     DiagnosticFactory3<KtExpression, PsiElement, String, PsiElement> UNSAFE_OPERATOR_CALL = DiagnosticFactory3.create(ERROR);
     DiagnosticFactory1<PsiElement, KotlinType> UNNECESSARY_SAFE_CALL = DiagnosticFactory1.create(WARNING);
-    DiagnosticFactory0<PsiElement> SAFE_CALL_WILL_CHANGE_NULLABILITY = DiagnosticFactory0.create(WARNING);
+    DiagnosticFactory0<KtQualifiedExpression> SAFE_CALL_WILL_CHANGE_NULLABILITY = DiagnosticFactory0.create(WARNING, PositioningStrategies.CALL_ELEMENT_WITH_DOT);
     DiagnosticFactory0<PsiElement> UNEXPECTED_SAFE_CALL = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory1<PsiElement, KotlinType> UNNECESSARY_NOT_NULL_ASSERTION = DiagnosticFactory1.create(WARNING);
     DiagnosticFactory0<PsiElement> NOT_NULL_ASSERTION_ON_LAMBDA_EXPRESSION = DiagnosticFactory0.create(WARNING);

compiler/testData/diagnostics/tests/SafeCallNonNullReceiver.kt

@@ -4,5 +4,5 @@
 
 fun ff() {
     val i: Int = 1
-    val a: Int = <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>i<!UNNECESSARY_SAFE_CALL!>?.<!>plus(2)<!>
+    val a: Int = i<!SAFE_CALL_WILL_CHANGE_NULLABILITY!><!UNNECESSARY_SAFE_CALL!>?.<!>plus(2)<!>
 }

compiler/testData/diagnostics/tests/controlFlowAnalysis/throwInLambda.fir.kt

@@ -8,6 +8,6 @@ fun foo(): String {
 }
 fun bar(): String {
     val x = fn() ?: return ""
-    val y = <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>x<!UNNECESSARY_SAFE_CALL!>?.<!>let { throw Exception() }<!> <!USELESS_ELVIS!>?: "unreachable"<!>
+    val y = x<!SAFE_CALL_WILL_CHANGE_NULLABILITY!><!UNNECESSARY_SAFE_CALL!>?.<!>let { throw Exception() }<!> <!USELESS_ELVIS!>?: "unreachable"<!>
     return y
 }

compiler/testData/diagnostics/tests/controlFlowAnalysis/throwInLambda.kt

@@ -8,6 +8,6 @@ fun foo(): String {
 }
 fun bar(): String {
     val x = fn() ?: return ""
-    <!UNREACHABLE_CODE!>val <!UNUSED_VARIABLE!>y<!> =<!> <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>x<!UNNECESSARY_SAFE_CALL!>?.<!>let { throw Exception() }<!> <!UNREACHABLE_CODE, USELESS_ELVIS!>?: "unreachable"<!>
+    <!UNREACHABLE_CODE!>val <!UNUSED_VARIABLE!>y<!> =<!> x<!SAFE_CALL_WILL_CHANGE_NULLABILITY!><!UNNECESSARY_SAFE_CALL!>?.<!>let { throw Exception() }<!> <!UNREACHABLE_CODE, USELESS_ELVIS!>?: "unreachable"<!>
     <!UNREACHABLE_CODE!>return y<!>
 }

compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.kt

@@ -0,0 +1,35 @@
+// FIR_IDENTICAL
+// LANGUAGE: -SafeCallsAreAlwaysNullable
+// DIAGNOSTICS: -UNNECESSARY_SAFE_CALL
+// ISSUE: KT-46860
+
+interface A {
+    fun id(): A
+
+    fun foo(): String
+}
+
+fun test_1(a: A) {
+    val s = a.id().id().id().id().id().id().id().id()<!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.foo()<!>.length
+}
+
+fun test_2(a: A) {
+    val s = a.id()
+        .id()
+        .id()
+        .id()
+        <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.id()<!>
+        .id()
+        .id()
+        .id()
+        <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.foo()<!>
+        <!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.length<!>
+}
+
+fun test_3(a: A) {
+    val s = a.id()<!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.
+        id()<!>.
+        id()<!SAFE_CALL_WILL_CHANGE_NULLABILITY!>?.
+        foo()<!>.
+        length
+}

compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.txt

@@ -0,0 +1,13 @@
+package
+
+public fun test_1(/*0*/ a: A): kotlin.Unit
+public fun test_2(/*0*/ a: A): kotlin.Unit
+public fun test_3(/*0*/ a: A): kotlin.Unit
+
+public interface A {
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public abstract fun foo(): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public abstract fun id(): A
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -21182,6 +21182,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/safeAccessOnUnit.kt");
             }
 
+            @Test
+            @TestMetadata("safeCallOnNotNullableType.kt")
+            public void testSafeCallOnNotNullableType() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/safeCallOnNotNullableType.kt");
+            }
+
             @Test
             @TestMetadata("safeCallOnTypeWithNullableUpperBound.kt")
             public void testSafeCallOnTypeWithNullableUpperBound() throws Exception {