SSR: match repeated variables correctly (IDEA-254329)

GitOrigin-RevId: 12514c6e4f3fa8c971e3f84d2439a68bd8a8eb31

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/MatchResultImpl.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.structuralsearch.impl.matcher;
 
 import com.intellij.psi.PsiElement;
@@ -114,7 +114,7 @@ public final class MatchResultImpl extends MatchResult {
     myMultipleMatch = multipleMatch;
   }
 
-  public MatchResultImpl findChild(@NotNull String name) {
+  public MatchResultImpl getChild(@NotNull String name) {
     // @todo this could be performance bottleneck, replace with hash lookup!
     for (final MatchResult match : myChildren) {
       final MatchResultImpl res = (MatchResultImpl)match;
@@ -126,12 +126,12 @@ public final class MatchResultImpl extends MatchResult {
     return null;
   }
 
-  public static MatchResultImpl findChildDeep(@NotNull MatchResult match, @NotNull String name) {
-    for (MatchResult child : match.getChildren()) {
+  public MatchResult findChild(@NotNull String name) {
+    for (MatchResult child : myChildren) {
       if (name.equals(child.getName())) {
-        return (MatchResultImpl)child;
+        return child;
       }
-      final MatchResultImpl deep = findChildDeep(child, name);
+      final MatchResult deep = ((MatchResultImpl)child).findChild(name);
       if (deep != null) {
         return deep;
       }

platform/structuralsearch/source/com/intellij/structuralsearch/impl/matcher/handlers/SubstitutionHandler.java

@@ -143,7 +143,7 @@ public class SubstitutionHandler extends MatchingHandler {
     if (result == null) {
       final MatchResultImpl previous = context.getPreviousResult();
       if (previous != null) {
-        result = MatchResultImpl.findChildDeep(previous, name);
+        result = previous.findChild(name);
       }
     }
 
@@ -187,7 +187,7 @@ public class SubstitutionHandler extends MatchingHandler {
   public void addResult(@NotNull PsiElement match, int start, int end, @NotNull MatchContext context) {
     if (totalMatchedOccurs == -1) {
       final MatchResultImpl matchResult = context.getResult();
-      final MatchResultImpl substitution = matchResult.findChild(name);
+      final MatchResultImpl substitution = matchResult.getChild(name);
 
       if (substitution == null) {
         matchResult.addChild(createMatch(match, start, end) );
@@ -294,7 +294,7 @@ public class SubstitutionHandler extends MatchingHandler {
 
   private void removeLastResults(int numberOfResults, @NotNull MatchContext context) {
     if (numberOfResults == 0) return;
-    final MatchResultImpl substitution = context.getResult().findChild(name);
+    final MatchResultImpl substitution = context.getResult().getChild(name);
 
     if (substitution != null) {
       if (substitution.hasChildren()) {
@@ -469,9 +469,9 @@ public class SubstitutionHandler extends MatchingHandler {
       totalMatchedOccurs = matchedOccurs;
       return true;
     }
-    MatchResult result = context.hasResult() ? context.getResult().findChild(name) : null;
+    MatchResult result = context.hasResult() ? context.getResult().getChild(name) : null;
     if (result == null && context.getPreviousResult() != null) {
-      result = context.getPreviousResult().findChild(name);
+      result = context.getPreviousResult().getChild(name);
     }
     return result == null || result.size() == matchedOccurs;
   }

platform/structuralsearch/testSource/com/intellij/structuralsearch/StructuralSearchTest.java

@@ -3380,6 +3380,16 @@ public class StructuralSearchTest extends StructuralSearchTestCase {
                                                                            "  @FindBy(name='_value)\n" +
                                                                            "  '_FieldType2 'field2 = '_init2?;\n" +
                                                                            "}"));
+
+    in = "class X {{" +
+         "  int[] newQueue = new int[queue.length * 2 - fwd];\n" +
+         "  System.arraycopy(queue, fwd, newQueue, 0, queue.length - fwd);" +
+         "}}";
+    assertEquals("should not match because the p var differs", 0,
+                 findMatchesCount(in, "int[] '_params = new int['_p - '_i];\n" +
+                                      "System.arraycopy('_a, '_i, '_params, 0, '_p - '_i);"));
+    assertEquals(1, findMatchesCount(in, "int[] '_params = new int['_p * 2 - '_i];\n" +
+                                         "System.arraycopy('_a, '_i, '_params, 0, '_p - '_i);"));
   }
 
   public void testForStatement() {