[Test] Add test for KT-53460

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -22924,6 +22924,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/kt58844.kt");
             }
 
+            @Test
+            @TestMetadata("notUselessComparasionAfterSmartcast.kt")
+            public void testNotUselessComparasionAfterSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.kt");
+            }
+
             @Test
             @TestMetadata("nullAssertOnTypeWithNullableUpperBound.kt")
             public void testNullAssertOnTypeWithNullableUpperBound() throws Exception {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -22924,6 +22924,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/kt58844.kt");
             }
 
+            @Test
+            @TestMetadata("notUselessComparasionAfterSmartcast.kt")
+            public void testNotUselessComparasionAfterSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.kt");
+            }
+
             @Test
             @TestMetadata("nullAssertOnTypeWithNullableUpperBound.kt")
             public void testNullAssertOnTypeWithNullableUpperBound() throws Exception {

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

@@ -22924,6 +22924,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/kt58844.kt");
             }
 
+            @Test
+            @TestMetadata("notUselessComparasionAfterSmartcast.kt")
+            public void testNotUselessComparasionAfterSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.kt");
+            }
+
             @Test
             @TestMetadata("nullAssertOnTypeWithNullableUpperBound.kt")
             public void testNullAssertOnTypeWithNullableUpperBound() throws Exception {

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

@@ -22930,6 +22930,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/kt58844.kt");
             }
 
+            @Test
+            @TestMetadata("notUselessComparasionAfterSmartcast.kt")
+            public void testNotUselessComparasionAfterSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.kt");
+            }
+
             @Test
             @TestMetadata("nullAssertOnTypeWithNullableUpperBound.kt")
             public void testNullAssertOnTypeWithNullableUpperBound() throws Exception {

compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.fir.kt

@@ -0,0 +1,14 @@
+// ISSUE: KT-53460
+
+fun test(a: String?, b: String?) {
+    if (a == null || a == "foo") {
+        when (b) {
+            "abc" -> return
+        }
+    }
+
+    a<!UNSAFE_CALL!>.<!>length // should be an error
+    if (a == null || a == "bar") { // comparasion to null is not useless
+        a<!UNSAFE_CALL!>.<!>length
+    }
+}

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

@@ -0,0 +1,14 @@
+// ISSUE: KT-53460
+
+fun test(a: String?, b: String?) {
+    if (a == null || a == "foo") {
+        when (b) {
+            "abc" -> return
+        }
+    }
+
+    <!DEBUG_INFO_SMARTCAST!>a<!>.length // should be an error
+    if (<!SENSELESS_COMPARISON!>a == null<!> || a == "bar") { // comparasion to null is not useless
+        <!DEBUG_INFO_SMARTCAST!>a<!>.length
+    }
+}

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

@@ -23762,6 +23762,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/nullableTypes/kt58844.kt");
             }
 
+            @Test
+            @TestMetadata("notUselessComparasionAfterSmartcast.kt")
+            public void testNotUselessComparasionAfterSmartcast() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/nullableTypes/notUselessComparasionAfterSmartcast.kt");
+            }
+
             @Test
             @TestMetadata("nullAssertOnTypeWithNullableUpperBound.kt")
             public void testNullAssertOnTypeWithNullableUpperBound() throws Exception {