Java: fix triple quote escape handling

in "Unnecessarily escaped character" inspection

GitOrigin-RevId: 662d5aacf82fadc8a6e980a350200e797d7f7828

java/java-impl/src/com/siyeh/ig/redundancy/UnnecessaryStringEscapeInspection.java

@@ -181,10 +181,11 @@ public final class UnnecessaryStringEscapeInspection extends BaseInspection impl
           else if (ch == '"' && doubleQuotes < 2) {
             if (i == end - 1) return -1;
             if (i == end - 2) return i - 1;
-            if (i < end - 2 && text.charAt(i + 1) == '"') {
-              if (doubleQuotes != 1 && text.charAt(i + 2) != '"') return i - 1;
+            if (doubleQuotes == 1) {
+              if (!text.startsWith("\"", i + 1) && !text.startsWith("\\\"", i + 1)) return i - 1;
             }
-            else {
+            else if (!text.startsWith("\"\"", i + 1) && !text.startsWith("\\\"\"", i + 1) &&
+                     !text.startsWith("\"\\\"", i + 1) && !text.startsWith("\\\"\\\"", i + 1)) {
               return i - 1;
             }
           }

java/java-tests/testData/ig/com/siyeh/igtest/redundancy/unnecessary_string_escape/NestedTextBlock.after.java

@@ -0,0 +1,7 @@
+class NestedTextBlock {
+  String s = """
+    String s = \"<caret>""
+        test
+    \""";
+""";
+}

java/java-tests/testData/ig/com/siyeh/igtest/redundancy/unnecessary_string_escape/NestedTextBlock.java

@@ -0,0 +1,7 @@
+class NestedTextBlock {
+  String s = """
+    String s = \"<warning descr="'\\\\"' is unnecessarily escaped"><caret>\"</warning><warning descr="'\\\\"' is unnecessarily escaped">\"</warning>
+        test
+    \"<warning descr="'\\\\"' is unnecessarily escaped">\"</warning><warning descr="'\\\\"' is unnecessarily escaped">\"</warning>;
+""";
+}

java/java-tests/testSrc/com/siyeh/ig/redundancy/UnnecessaryStringEscapeInspectionTest.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.siyeh.ig.redundancy;
 
 import com.intellij.codeInspection.InspectionProfileEntry;
@@ -20,6 +20,7 @@ public class UnnecessaryStringEscapeInspectionTest extends LightJavaInspectionTe
   public void testEscapedNewLine() { doQuickFixTest(); }
   public void testStringTemplate1() { doQuickFixTest(); }
   public void testStringTemplate2() { doQuickFixTest(); }
+  public void testNestedTextBlock() { doQuickFixTest(); }
 
   public void testEscapedNewLineNotUnnecessary() { doTest(); }
   public void testBrokenCode() { doTest(); }