[CMI] Replace StringBuffer with StringBuilder in CodeMetaInfoRenderer

compiler/tests-common/tests/org/jetbrains/kotlin/codeMetaInfo/CodeMetaInfoRenderer.kt

@@ -9,59 +9,68 @@ import com.intellij.util.containers.Stack
 import org.jetbrains.kotlin.checkers.utils.CheckerTestUtil
 import org.jetbrains.kotlin.codeMetaInfo.model.CodeMetaInfo
 import java.io.File
+import java.lang.StringBuilder
 
 object CodeMetaInfoRenderer {
     fun renderTagsToText(
         codeMetaInfos: List<CodeMetaInfo>,
         originalText: String
-    ): StringBuffer {
+    ): StringBuilder {
-        val result = StringBuffer()
+        return StringBuilder().apply {
+            renderTagsToText(this, codeMetaInfos, originalText)
+        }
+    }
+
+    fun renderTagsToText(
+        builder: StringBuilder,
+        codeMetaInfos: List<CodeMetaInfo>,
+        originalText: String
+    ) {
         if (codeMetaInfos.isEmpty()) {
-            result.append(originalText)
+            builder.append(originalText)
-            return result
+            return
         }
         val sortedMetaInfos = getSortedCodeMetaInfos(codeMetaInfos)
         val opened = Stack<CodeMetaInfo>()
 
         for ((i, c) in originalText.withIndex()) {
-            checkOpenedAndCloseStringIfNeeded(opened, i, result)
+            checkOpenedAndCloseStringIfNeeded(opened, i, builder)
             val matchedCodeMetaInfos = sortedMetaInfos.filter { it.start == i }
             if (matchedCodeMetaInfos.isNotEmpty()) {
-                openStartTag(result)
+                openStartTag(builder)
                 val iterator = matchedCodeMetaInfos.listIterator()
                 var current: CodeMetaInfo? = iterator.next()
 
                 while (current != null) {
                     val next: CodeMetaInfo? = if (iterator.hasNext()) iterator.next() else null
                     opened.push(current)
-                    result.append(current.asString())
+                    builder.append(current.asString())
                     when {
                         next == null ->
-                            closeStartTag(result)
+                            closeStartTag(builder)
                         next.end == current.end ->
-                            result.append(", ")
+                            builder.append(", ")
                         else ->
-                            closeStartAndOpenNewTag(result)
+                            closeStartAndOpenNewTag(builder)
                     }
                     current = next
                 }
             }
-            result.append(c)
+            builder.append(c)
         }
-        checkOpenedAndCloseStringIfNeeded(opened, originalText.length, result)
+        checkOpenedAndCloseStringIfNeeded(opened, originalText.length, builder)
-        return result
     }
 
     private fun getSortedCodeMetaInfos(metaInfos: Collection<CodeMetaInfo>): List<CodeMetaInfo> {
         return metaInfos.sortedWith(compareBy<CodeMetaInfo> { it.start }.then(compareByDescending { it.end }))
     }
 
-    private fun closeString(result: StringBuffer) = result.append("<!>")
+    private fun closeString(result: StringBuilder) = result.append("<!>")
-    private fun openStartTag(result: StringBuffer) = result.append("<!")
+    private fun openStartTag(result: StringBuilder) = result.append("<!")
-    private fun closeStartTag(result: StringBuffer) = result.append("!>")
+    private fun closeStartTag(result: StringBuilder) = result.append("!>")
-    private fun closeStartAndOpenNewTag(result: StringBuffer) = result.append("!><!")
+    private fun closeStartAndOpenNewTag(result: StringBuilder) = result.append("!><!")
 
-    private fun checkOpenedAndCloseStringIfNeeded(opened: Stack<CodeMetaInfo>, end: Int, result: StringBuffer) {
+    private fun checkOpenedAndCloseStringIfNeeded(opened: Stack<CodeMetaInfo>, end: Int, result: StringBuilder) {
         var prev: CodeMetaInfo? = null
         while (!opened.isEmpty() && end == opened.peek().end) {
             if (prev == null || prev.start != opened.peek().start)