PSI: Make JetPostfixExpression.getBaseExpression() nullable

#KT-7761 Fixed

compiler/frontend.java/src/org/jetbrains/kotlin/load/kotlin/KotlinJvmCheckerProvider.kt

@@ -223,7 +223,7 @@ public class JavaNullabilityWarningsChecker : AdditionalTypeChecker {
         when (expression) {
             is JetPostfixExpression ->
                     if (expression.getOperationToken() == JetTokens.EXCLEXCL) {
-                        val baseExpression = expression.getBaseExpression()
+                        val baseExpression = expression.getBaseExpression() ?: return
                         val baseExpressionType = c.trace.getType(baseExpression) ?: return
                         doIfNotNull(
                                 DataFlowValueFactory.createDataFlowValue(baseExpression, baseExpressionType, c),

compiler/frontend/src/org/jetbrains/kotlin/psi/JetPostfixExpression.java

@@ -17,7 +17,9 @@
 package org.jetbrains.kotlin.psi;
 
 import com.intellij.lang.ASTNode;
+import com.intellij.psi.util.PsiTreeUtil;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 public class JetPostfixExpression extends JetUnaryExpression {
     public JetPostfixExpression(@NotNull ASTNode node) {
@@ -25,11 +27,9 @@ public class JetPostfixExpression extends JetUnaryExpression {
     }
 
     @Override
-    @NotNull
+    @Nullable @IfNotParsed
     public JetExpression getBaseExpression() {
-        JetExpression answer = findChildByClass(JetExpression.class);
+        return PsiTreeUtil.getPrevSiblingOfType(getOperationReference(), JetExpression.class);
-        assert answer != null;
-        return answer;
     }
 
     @Override

compiler/testData/cfg/bugs/kt7761.instructions

@@ -0,0 +1,81 @@
+== UnitIncDec ==
+class UnitIncDec() {
+    fun inc() : Unit {}
+    fun dec() : Unit {}
+}
+---------------------
+L0:
+  1 <START>
+L1:
+    <END>      NEXT:[<SINK>]
+error:
+    <ERROR>    PREV:[]
+sink:
+    <SINK>     PREV:[<ERROR>, <END>]
+=====================
+== inc ==
+fun inc() : Unit {}
+---------------------
+L0:
+  1 <START>
+  2 mark({})
+    read (Unit)
+L1:
+  1 <END>          NEXT:[<SINK>]
+error:
+    <ERROR>        PREV:[]
+sink:
+    <SINK>         PREV:[<ERROR>, <END>]
+=====================
+== dec ==
+fun dec() : Unit {}
+---------------------
+L0:
+  1 <START>
+  2 mark({})
+    read (Unit)
+L1:
+  1 <END>          NEXT:[<SINK>]
+error:
+    <ERROR>        PREV:[]
+sink:
+    <SINK>         PREV:[<ERROR>, <END>]
+=====================
+== testUnitIncDec ==
+fun testUnitIncDec() {
+    var x = UnitIncDec()
+    x = <warning>x<error>++</error></warning>
+}
+---------------------
+L0:
+  1 <START>
+  2 mark({ var x = UnitIncDec() x = <warning>x<error>++</error></warning> })
+    v(var x = UnitIncDec())
+    mark(UnitIncDec())
+    call(UnitIncDec(), <init>) -> <v0>
+    w(x|<v0>)
+    mark(<warning>)
+    magic[UNRESOLVED_CALL](<warning>) -> <v1>
+    mark(<warning>x<)
+    call(<warning>x<, <ERROR FUNCTION>|<v1>) -> <v2>
+    magic[VALUE_CONSUMER](>++|!<v3>) -> <v4>
+    mark(<warning>x<error>++)
+    call(<warning>x<error>++, <ERROR FUNCTION>|<v2>) -> <v5>
+    mark(/error>)
+    magic[UNRESOLVED_CALL](/error>) -> <v6>
+    magic[VALUE_CONSUMER](/error>|<v6>) -> <v7>
+    mark(<warning>x<error>++</error>)
+    call(<warning>x<error>++</error>, <ERROR FUNCTION>|<v5>) -> <v8>
+    mark(/warning>)
+    magic[UNRESOLVED_CALL](/warning>) -> <v9>
+    magic[VALUE_CONSUMER](/warning>|<v9>) -> <v10>
+    mark(<warning>x<error>++</error></warning>)
+    call(<warning>x<error>++</error></warning>, <ERROR FUNCTION>|<v8>) -> <v11>
+    w(x|<v11>)
+L1:
+  1 <END>                                                                          NEXT:[<SINK>]
+error:
+    <ERROR>                                                                        PREV:[]
+sink:
+    <SINK>                                                                         PREV:[<ERROR>, <END>]
+=====================

compiler/testData/cfg/bugs/kt7761.kt

@@ -0,0 +1,9 @@
+class UnitIncDec() {
+    fun inc() : Unit {}
+    fun dec() : Unit {}
+}
+
+fun testUnitIncDec() {
+    var x = UnitIncDec()
+    x = <warning>x<error>++</error></warning>
+}

compiler/testData/cfg/bugs/kt7761.values

@@ -0,0 +1,36 @@
+== UnitIncDec ==
+class UnitIncDec() {
+    fun inc() : Unit {}
+    fun dec() : Unit {}
+}
+---------------------
+=====================
+== inc ==
+fun inc() : Unit {}
+---------------------
+=====================
+== dec ==
+fun dec() : Unit {}
+---------------------
+=====================
+== testUnitIncDec ==
+fun testUnitIncDec() {
+    var x = UnitIncDec()
+    x = <warning>x<error>++</error></warning>
+}
+---------------------
+                                                                     <v10>: *            NEW: magic[VALUE_CONSUMER](/warning>|<v9>) -> <v10>
+                                                                     <v4>: *             NEW: magic[VALUE_CONSUMER](>++|!<v3>) -> <v4>
+                                                                     <v7>: *             NEW: magic[VALUE_CONSUMER](/error>|<v6>) -> <v7>
+UnitIncDec()                                                         <v0>: UnitIncDec    NEW: call(UnitIncDec(), <init>) -> <v0>
+<warning>                                                            <v1>: *             NEW: magic[UNRESOLVED_CALL](<warning>) -> <v1>
+<warning>x<                                                          <v2>: *             NEW: call(<warning>x<, <ERROR FUNCTION>|<v1>) -> <v2>
+>++                                                                  !<v3>: *
+<warning>x<error>++                                                  <v5>: *             NEW: call(<warning>x<error>++, <ERROR FUNCTION>|<v2>) -> <v5>
+/error>                                                              <v6>: *             NEW: magic[UNRESOLVED_CALL](/error>) -> <v6>
+<warning>x<error>++</error>                                          <v8>: *             NEW: call(<warning>x<error>++</error>, <ERROR FUNCTION>|<v5>) -> <v8>
+/warning>                                                            <v9>: *             NEW: magic[UNRESOLVED_CALL](/warning>) -> <v9>
+<warning>x<error>++</error></warning>                                <v11>: UnitIncDec   NEW: call(<warning>x<error>++</error></warning>, <ERROR FUNCTION>|<v8>) -> <v11>
+x = <warning>x<error>++</error></warning>                            !<v12>: *
+{ var x = UnitIncDec() x = <warning>x<error>++</error></warning> }   !<v12>: *           COPY
+=====================

compiler/tests/org/jetbrains/kotlin/cfg/ControlFlowTestGenerated.java

@@ -144,6 +144,12 @@ public class ControlFlowTestGenerated extends AbstractControlFlowTest {
             String fileName = JetTestUtils.navigationMetadata("compiler/testData/cfg/bugs/jumpToOuterScope.kt");
             doTest(fileName);
         }
+
+        @TestMetadata("kt7761.kt")
+        public void testKt7761() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/cfg/bugs/kt7761.kt");
+            doTest(fileName);
+        }
     }
 
     @TestMetadata("compiler/testData/cfg/controlStructures")

compiler/tests/org/jetbrains/kotlin/cfg/PseudoValueTestGenerated.java

@@ -146,6 +146,12 @@ public class PseudoValueTestGenerated extends AbstractPseudoValueTest {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/cfg/bugs/jumpToOuterScope.kt");
                 doTest(fileName);
             }
+
+            @TestMetadata("kt7761.kt")
+            public void testKt7761() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/cfg/bugs/kt7761.kt");
+                doTest(fileName);
+            }
         }
 
         @TestMetadata("compiler/testData/cfg/controlStructures")

idea/ide-common/src/org/jetbrains/kotlin/resolve/lazy/PartialBodyResolveFilter.kt

@@ -174,7 +174,7 @@ class PartialBodyResolveFilter(
                 expression.acceptChildren(this)
 
                 if (expression.getOperationToken() == JetTokens.EXCLEXCL) {
-                    addIfCanBeSmartCast(expression.getBaseExpression())
+                    addIfCanBeSmartCast(expression.getBaseExpression() ?: return)
                 }
             }
 

idea/idea-analysis/src/org/jetbrains/kotlin/idea/intentions/OperatorToFunctionIntention.kt

@@ -40,6 +40,7 @@ public class OperatorToFunctionIntention : JetSelfTargetingIntention<JetExpressi
         private fun isApplicablePostfix(element: JetPostfixExpression, caretOffset: Int): Boolean {
             val opRef = element.getOperationReference()
             if (!opRef.getTextRange().containsOffset(caretOffset)) return false
+            if (element.getBaseExpression() == null) return false
             return when (opRef.getReferencedNameElementType()) {
                 JetTokens.PLUSPLUS, JetTokens.MINUSMINUS -> true
                 else -> false
@@ -98,7 +99,7 @@ public class OperatorToFunctionIntention : JetSelfTargetingIntention<JetExpressi
 
         private fun convertPostFix(element: JetPostfixExpression): JetExpression {
             val op = element.getOperationReference().getReferencedNameElementType()
-            val base = element.getBaseExpression().getText()
+            val base = element.getBaseExpression()!!.getText()
 
             val call = when (op) {
                 JetTokens.PLUSPLUS -> "inc()"

idea/idea-core/src/org/jetbrains/kotlin/idea/core/refactoring/JetNameSuggester.java

@@ -224,7 +224,12 @@ public class JetNameSuggester {
         return matcher.replaceAll("");
     }
     
-    private static void addNamesForExpression(final ArrayList<String> result, JetExpression expression, final JetNameValidator validator) {
+    private static void addNamesForExpression(
+            final ArrayList<String> result,
+            @Nullable JetExpression expression,
+            final JetNameValidator validator) {
+        if (expression == null) return;
+
         expression.accept(new JetVisitorVoid() {
             @Override
             public void visitQualifiedExpression(@NotNull JetQualifiedExpression expression) {

idea/src/org/jetbrains/kotlin/idea/intentions/branchedTransformations/intentions/DoubleBangToIfThenIntention.kt

@@ -37,11 +37,14 @@ import org.jetbrains.kotlin.resolve.bindingContextUtil.isUsedAsStatement
 
 public class DoubleBangToIfThenIntention : JetSelfTargetingRangeIntention<JetPostfixExpression>(javaClass(), "Replace '!!' expression with 'if' expression") {
     override fun applicabilityRange(element: JetPostfixExpression): TextRange? {
-        return if (element.getOperationToken() == JetTokens.EXCLEXCL)  element.getOperationReference().getTextRange() else null
+        return if (element.getOperationToken() == JetTokens.EXCLEXCL && element.getBaseExpression() != null)
+            element.getOperationReference().getTextRange()
+        else
+            null
     }
 
     override fun applyTo(element: JetPostfixExpression, editor: Editor) {
-        val base = JetPsiUtil.safeDeparenthesize(element.getBaseExpression())
+        val base = JetPsiUtil.safeDeparenthesize(element.getBaseExpression()!!)
         val expressionText = formatForUseInExceptionArgument(base.getText()!!)
 
         val defaultException = JetPsiFactory(element).createExpression("throw NullPointerException()")

idea/src/org/jetbrains/kotlin/idea/quickfix/ExclExclCallFix.java

@@ -168,7 +168,7 @@ public class ExclExclCallFix implements IntentionAction {
             PsiElement parent = exclExclElement.getParent();
             if (parent != null) {
                 PsiElement operationParent = parent.getParent();
-                if (operationParent instanceof JetPostfixExpression) {
+                if (operationParent instanceof JetPostfixExpression && ((JetPostfixExpression) operationParent).getBaseExpression() != null) {
                     return (JetPostfixExpression) operationParent;
                 }
             }