Fix NPE in JavaNullabilityChecker when checking equals-calls

This NPE was introduced in ce41b5745a
Prior to the latter change there was a synthetic PSI element for each
equals-related call, thus callOperationNode was not null here.

== are intentionally treated as safe calls, but for nullability checker
it's not relevant, it only should report warnings on real safe-calls

compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JavaNullabilityChecker.kt

@@ -109,8 +109,9 @@ class JavaNullabilityChecker : AdditionalTypeChecker {
         }
 
         if (safeAccess) {
+            val safeAccessElement = c.call.callOperationNode?.psi ?: return
             doIfNotNull(receiverArgument.type, { dataFlowValue }, c) {
-                c.trace.report(Errors.UNNECESSARY_SAFE_CALL.on(c.call.callOperationNode!!.psi, receiverArgument.type))
+                c.trace.report(Errors.UNNECESSARY_SAFE_CALL.on(safeAccessElement, receiverArgument.type))
             }
 
             return

compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.kt

@@ -0,0 +1,49 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_PARAMETER
+// JSR305_GLOBAL_REPORT warn
+
+// FILE: spr/NonNullApi.java
+
+package spr;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import javax.annotation.Nonnull;
+import javax.annotation.meta.TypeQualifierDefault;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+@Nonnull
+@TypeQualifierDefault({ElementType.METHOD, ElementType.PARAMETER})
+public @interface NonNullApi {
+}
+
+// FILE: A.java
+
+import spr.*;
+
+@NonNullApi
+public class A {
+    public String getBar() {
+        return "";
+    }
+}
+
+// FILE: main.kt
+
+fun main(a: A) {
+    if (a.getBar() == "1" && a.hashCode() != 0) return
+    if (a.getBar() != "2" && a.hashCode() != 0) return
+
+    if (<!SENSELESS_COMPARISON!>a.getBar() == null<!> && a.hashCode() != 0) return
+    if (<!SENSELESS_COMPARISON!>a.getBar() != null<!> && a.hashCode() != 0) return
+
+    if (a.bar == "1" && a.hashCode() != 0) return
+    if (a.bar != "2" && a.hashCode() != 0) return
+
+    if (<!SENSELESS_COMPARISON!>a.bar == null<!> && a.hashCode() != 0) return
+    if (<!SENSELESS_COMPARISON!>a.bar != null<!> && a.hashCode() != 0) return
+}

compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.txt

@@ -0,0 +1,21 @@
+package
+
+public fun main(/*0*/ a: A): kotlin.Unit
+
+@spr.NonNullApi public open class A {
+    public constructor A()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open fun getBar(): kotlin.String!
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}
+
+package spr {
+
+    @kotlin.annotation.Target(allowedTargets = {AnnotationTarget.CLASS, AnnotationTarget.FILE}) @kotlin.annotation.Retention(value = AnnotationRetention.RUNTIME) @kotlin.annotation.MustBeDocumented @javax.annotation.Nonnull @javax.annotation.meta.TypeQualifierDefault(value = {ElementType.METHOD, ElementType.PARAMETER}) public final annotation class NonNullApi : kotlin.Annotation {
+        public constructor NonNullApi()
+        public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+        public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+        public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+    }
+}

compiler/tests/org/jetbrains/kotlin/checkers/ForeignAnnotationsNoAnnotationInClasspathTestGenerated.java

@@ -294,6 +294,12 @@ public class ForeignAnnotationsNoAnnotationInClasspathTestGenerated extends Abst
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
                 }
 
+                @TestMetadata("equalsOnNonNull.kt")
+                public void testEqualsOnNonNull() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("fieldsAreNullable.kt")
                 public void testFieldsAreNullable() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/fieldsAreNullable.kt");

compiler/tests/org/jetbrains/kotlin/checkers/ForeignAnnotationsNoAnnotationInClasspathWithFastClassReadingTestGenerated.java

@@ -294,6 +294,12 @@ public class ForeignAnnotationsNoAnnotationInClasspathWithFastClassReadingTestGe
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
                 }
 
+                @TestMetadata("equalsOnNonNull.kt")
+                public void testEqualsOnNonNull() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("fieldsAreNullable.kt")
                 public void testFieldsAreNullable() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/fieldsAreNullable.kt");

compiler/tests/org/jetbrains/kotlin/checkers/ForeignAnnotationsTestGenerated.java

@@ -294,6 +294,12 @@ public class ForeignAnnotationsTestGenerated extends AbstractForeignAnnotationsT
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
                 }
 
+                @TestMetadata("equalsOnNonNull.kt")
+                public void testEqualsOnNonNull() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("fieldsAreNullable.kt")
                 public void testFieldsAreNullable() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/fieldsAreNullable.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/JavacForeignAnnotationsTestGenerated.java

@@ -294,6 +294,12 @@ public class JavacForeignAnnotationsTestGenerated extends AbstractJavacForeignAn
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
                 }
 
+                @TestMetadata("equalsOnNonNull.kt")
+                public void testEqualsOnNonNull() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/equalsOnNonNull.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("fieldsAreNullable.kt")
                 public void testFieldsAreNullable() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/foreignAnnotations/tests/jsr305/nullabilityWarnings/typeQualifierDefault/fieldsAreNullable.kt");