CPP-12350 Implement calculation of indentation in line from the information of the lexer

* SO inside indent calculation
* line-wide comment as indent anchor
* indent in pure blocks
* improvements in shared indent calculator for enclosed statements

java/java-impl/src/com/intellij/codeInsight/editorActions/JavaLineIndentProvider.java

@@ -26,10 +26,11 @@ import com.intellij.psi.TokenType;
 import com.intellij.psi.impl.source.codeStyle.SemanticEditorPosition;
 import com.intellij.psi.impl.source.codeStyle.lineIndent.JavaLikeLangLineIndentProvider;
 import com.intellij.psi.tree.IElementType;
-import java.util.HashMap;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashMap;
+
 import static com.intellij.formatting.Indent.Type.CONTINUATION;
 import static com.intellij.psi.impl.source.codeStyle.lineIndent.JavaLikeLangLineIndentProvider.JavaLikeElement.*;
 
@@ -51,6 +52,7 @@ public class JavaLineIndentProvider extends JavaLikeLangLineIndentProvider {
     SYNTAX_MAP.put(JavaTokenType.CASE_KEYWORD, SwitchCase);
     SYNTAX_MAP.put(JavaTokenType.DEFAULT_KEYWORD, SwitchDefault);
     SYNTAX_MAP.put(JavaTokenType.IF_KEYWORD, IfKeyword);
+    SYNTAX_MAP.put(JavaTokenType.WHILE_KEYWORD, IfKeyword);    
     SYNTAX_MAP.put(JavaTokenType.ELSE_KEYWORD, ElseKeyword);
     SYNTAX_MAP.put(JavaTokenType.FOR_KEYWORD, ForKeyword);
     SYNTAX_MAP.put(JavaTokenType.DO_KEYWORD, DoKeyword);

java/java-tests/testSrc/com/intellij/java/psi/formatter/java/JavaEnterActionTest.java

@@ -215,6 +215,55 @@ public class JavaEnterActionTest extends AbstractEnterActionTestCase {
                ") {}");
   }
 
+  public void testEnter_AfterStatementWithoutBlock() throws IOException {
+    doTextTest("java",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            while (true) <caret>\n" +
+               "    }\n" +
+               "}\n",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            while (true) \n" +
+               "                <caret>\n" +
+               "    }\n" +
+               "}\n");
+
+    doTextTest("java",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            while (true) {<caret>\n" +
+               "    }\n" +
+               "}\n",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            while (true) {\n" +
+               "                <caret>\n" +
+               "            }\n" +
+               "    }\n" +
+               "}\n");
+
+    doTextTest("java",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            try {<caret>\n" +
+               "    }\n" +
+               "}\n",
+               "class T {\n" +
+               "    void test() {\n" +
+               "        if (true)\n" +
+               "            try {\n" +
+               "                <caret>\n" +
+               "            }\n" +
+               "    }\n" +
+               "}\n");
+  }
+
   public void testEnter_AfterStatementWithLabel() throws IOException {
     // as prev
     doTextTest("java",

platform/lang-impl/src/com/intellij/psi/impl/source/codeStyle/SemanticEditorPosition.java

@@ -30,6 +30,8 @@ import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
 
+import static java.lang.Integer.min;
+
 /**
  * @author Rustam Vishnyakov
  */
@@ -305,7 +307,11 @@ public class SemanticEditorPosition {
 
   @Override
   public String toString() {
-    return myIterator.getTokenType().toString();
+    return myIterator.atEnd() 
+       ? "atEnd"
+       : myIterator.getTokenType().toString() 
+         + "=>" 
+         + getChars().subSequence(getStartOffset(), min(getStartOffset() + 255, getChars().length()));
   }
 
   public SemanticEditorPosition copy() {

platform/lang-impl/src/com/intellij/psi/impl/source/codeStyle/lineIndent/JavaLikeLangLineIndentProvider.java

@@ -287,6 +287,9 @@ public abstract class JavaLikeLangLineIndentProvider implements LineIndentProvid
         position.moveBeforeParentheses(ArrayOpeningBracket, ArrayClosingBracket);
         continue;
       }
+      else if (isStartOfStatementWithOptionalBlock(position)) {
+        return position.getStartOffset();
+      }
       else if (position.isAtAnyOf(Semicolon,
                                   BlockOpeningBrace, 
                                   BlockComment, 
@@ -294,7 +297,7 @@ public abstract class JavaLikeLangLineIndentProvider implements LineIndentProvid
                                   LeftParenthesis,
                                   LanguageStartDelimiter) ||
                (position.getLanguage() != Language.ANY) && !position.isAtLanguage(currLanguage)) {
-        SemanticEditorPosition statementStart = getPosition(position.getEditor(), position.getStartOffset());
+        SemanticEditorPosition statementStart = position.copy();
         statementStart = statementStart.after().afterOptionalMix(Whitespace, LineComment);
         if (!isIndentProvider(statementStart, ignoreLabels)) {
           final SemanticEditorPosition maybeColon = statementStart.afterOptionalMix(Whitespace, BlockComment).after();
@@ -315,6 +318,21 @@ public abstract class JavaLikeLangLineIndentProvider implements LineIndentProvid
     return 0;
   }
 
+  /**
+   * Returns {@code true} if the {@code position} starts the statement that <i>can</i> have a code block.
+   * In C-kile languages it is one of {@code if, else, for, while, do, try}. 
+   * 
+   * @param position
+   */
+  protected boolean isStartOfStatementWithOptionalBlock(@NotNull SemanticEditorPosition position) {
+    return position.isAtAnyOf(
+      ElseKeyword,
+      IfKeyword,
+      ForKeyword,
+      TryKeyword,
+      DoKeyword);
+  }
+
   private static boolean atBlockStartAndNeedBlockIndent(@NotNull SemanticEditorPosition position) {
     return position.isAt(BlockOpeningBrace);
   }