From 552987fbcf0cda2f019e8509e2967e6c85df8f6c Mon Sep 17 00:00:00 2001
From: Tagir Valeev <tagir.valeev@jetbrains.com>
Date: Mon, 26 Sep 2022 15:22:44 +0200
Subject: [PATCH] [java-dfa] IDEA-302493 Update nullability for overridden
 methods with 'get' prefix when qualifier type is constrained and subclass
 method has different nullability

GitOrigin-RevId: 6b9e819d236ebec069923f0647b9e42f30d89698
---
 .../java/inst/MethodCallInstruction.java      | 27 +++++------------
 .../fixture/RewiringSubclassMethod.java       | 29 +++++++++++++++++++
 .../DataFlowInspectionTest.java               |  1 +
 3 files changed, 38 insertions(+), 19 deletions(-)
 create mode 100644 java/java-tests/testData/inspection/dataFlow/fixture/RewiringSubclassMethod.java

diff --git a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/java/inst/MethodCallInstruction.java b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/java/inst/MethodCallInstruction.java
index bb08feedfeee..8a3b1e0aa98d 100644
--- a/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/java/inst/MethodCallInstruction.java
+++ b/java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/java/inst/MethodCallInstruction.java
@@ -260,14 +260,6 @@ public class MethodCallInstruction extends ExpressionPushingInstruction {
     return myContext;
   }
 
-  public @Nullable DfaValue getPrecalculatedReturnValue() {
-    return myPrecalculatedReturnValue;
-  }
-
-  public @NotNull Nullability getReturnNullability() {
-    return myReturnNullability;
-  }
-
   public String toString() {
     if (myContext instanceof PsiCall) {
       return "CALL_METHOD: " + myContext.getText();
@@ -363,23 +355,20 @@ public class MethodCallInstruction extends ExpressionPushingInstruction {
                                                  @NotNull DfaMemoryState state, 
                                                  @NotNull DfaValueFactory factory, 
                                                  PsiMethod realMethod) {
-    if (callArguments.getArguments() != null) {
-      PsiMethod method = myTargetMethod;
-      if (method != null) {
-        CustomMethodHandlers.CustomMethodHandler handler = CustomMethodHandlers.find(method);
-        if (handler != null) {
-          DfaValue value = handler.getMethodResultValue(callArguments, state, factory, method);
-          if (value != null) {
-            return value;
-          }
+    if (callArguments.getArguments() != null && myTargetMethod != null) {
+      CustomMethodHandlers.CustomMethodHandler handler = CustomMethodHandlers.find(myTargetMethod);
+      if (handler != null) {
+        DfaValue value = handler.getMethodResultValue(callArguments, state, factory, myTargetMethod);
+        if (value != null) {
+          return value;
         }
       }
     }
     DfaValue qualifierValue = callArguments.getQualifier();
-    DfaValue precalculated = getPrecalculatedReturnValue();
+    DfaValue precalculated = myPrecalculatedReturnValue;
     PsiType type = getResultType();
 
-    VariableDescriptor descriptor = JavaDfaValueFactory.getAccessedVariableOrGetter(myTargetMethod);
+    VariableDescriptor descriptor = JavaDfaValueFactory.getAccessedVariableOrGetter(realMethod);
     if (descriptor instanceof SpecialField || descriptor != null && qualifierValue instanceof DfaVariableValue) {
       return descriptor.createValue(factory, qualifierValue);
     }
diff --git a/java/java-tests/testData/inspection/dataFlow/fixture/RewiringSubclassMethod.java b/java/java-tests/testData/inspection/dataFlow/fixture/RewiringSubclassMethod.java
new file mode 100644
index 000000000000..bb90bf2a319f
--- /dev/null
+++ b/java/java-tests/testData/inspection/dataFlow/fixture/RewiringSubclassMethod.java
@@ -0,0 +1,29 @@
+// IDEA-302493
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class RewiringSubclassMethod {
+  void test(Parent parent) {
+    if (parent instanceof C1 || parent instanceof C2) {
+      String s = parent.readString();
+      System.out.println(s.trim());
+      String s2 = parent.getString();
+      System.out.println(s2.trim());
+    }
+  }
+
+  interface Parent {
+    @Nullable String readString();
+    @Nullable String getString();
+  }
+
+  interface C1 extends Parent {
+    @NotNull String readString();
+    @NotNull String getString();
+  }
+
+  interface C2 extends Parent {
+    @NotNull String readString();
+    @NotNull String getString();
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java b/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
index f876ba39645a..66974144191f 100644
--- a/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
+++ b/java/java-tests/testSrc/com/intellij/java/codeInspection/DataFlowInspectionTest.java
@@ -723,4 +723,5 @@ public class DataFlowInspectionTest extends DataFlowInspectionTestCase {
   public void testNestedVersusSuper() { doTest(); }
   public void testChangeFieldUsedInPureMethod() { doTest(); }
   public void testSuppression() { doTest(); }
+  public void testRewiringSubclassMethod() { doTest(); }
 }