StringConcatenationInLoopsInspection: automatically create append chains

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/stringConcatInLoop/afterConcatSimple.java

@@ -4,6 +4,7 @@ public class Main {
     String test(String[] strings) {
         StringBuilder res = new StringBuilder();
         for (String s : strings) {
+            res.append(s).append("\n");
             res.append(s);
         }
         return res.toString();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/stringConcatInLoop/afterConcatWithDelimiter.java

@@ -8,7 +8,12 @@ public class Main {
             if (/*before*/res.length() > 0) {
                 res.append(", ");
             }
-            res.append(s);
+            if (s.contains("'")) {
+                res.append('[' // bracket
+                ).append(s).append(']');
+            } else {
+                res.append(s);
+            }
         }
         return res.toString();
     }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/stringConcatInLoop/beforeConcatSimple.java

@@ -4,7 +4,8 @@ public class Main {
     String test(String[] strings) {
         String res = "";
         for (String s : strings) {
-            res <caret>+= s;
+            res <caret>+= s + "\n";
+            res += s;
         }
         return res;
     }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/stringConcatInLoop/beforeConcatWithDelimiter.java

@@ -7,7 +7,12 @@ public class Main {
             if (/*before*/!res/*within*/.isEmpty()) {
                 res += ", ";
             }
-            res = (res <caret>+ s);
+            if (s.contains("'")) {
+                res = (res <caret>+ '[' // bracket
+                                  + s + ']');
+            } else {
+                res = (res + s);
+            }
         }
         return res;
     }