private void generateRootParserContent()

in src/org/intellij/grammar/generator/ParserGenerator.java [530:606]
76 lines of code
22 McCabe index (conditional complexity)

  private void generateRootParserContent() {
    BnfRule rootRule = myFile.getRule(myGrammarRoot);
    List<BnfRule> extraRoots = new ArrayList<>();
    for (String ruleName : myRuleInfos.keySet()) {
      BnfRule rule = Objects.requireNonNull(myFile.getRule(ruleName));
      if (getAttribute(rule, KnownAttribute.ELEMENT_TYPE) != null) continue;
      if (!hasElementType(rule)) continue;
      if (Rule.isFake(rule) || Rule.isMeta(rule)) continue;
      ExpressionHelper.ExpressionInfo info = myExpressionHelper.getExpressionInfo(rule);
      if (info != null && info.rootRule != rule) continue;
      if (!Boolean.TRUE.equals(getAttribute(rule, KnownAttribute.EXTRA_ROOT))) continue;
      extraRoots.add(rule);
    }

    List<Set<String>> extendsSet = buildExtendsSet(myGraphHelper.getRuleExtendsMap());
    boolean generateExtendsSets = !extendsSet.isEmpty();
    String shortET = shorten(C.IElementTypeClass);
    String shortAN = shorten(C.AstNodeClass);
    String shortPB = shorten(C.PsiBuilderClass);
    String shortTS = shorten(C.TokenSetClass);
    String shortMarker = !G.generateFQN ? "Marker" : C.PsiBuilderClass + ".Marker";
    out("public %s parse(%s %s, %s %s) {", shortAN, shortET, N.root, shortPB, N.builder);
    out("parseLight(%s, %s);", N.root, N.builder);
    out("return %s.getTreeBuilt();", N.builder);
    out("}");
    newLine();
    out("public void parseLight(%s %s, %s %s) {", shortET, N.root, shortPB, N.builder);
    out("boolean %s;", N.result);
    out("%s = adapt_builder_(%s, %s, this, %s);", N.builder, N.root, N.builder, generateExtendsSets ? "EXTENDS_SETS_" : null);
    out("%s %s = enter_section_(%s, 0, _COLLAPSE_, null);", shortMarker, N.marker, N.builder);
    out("%s = parse_root_(%s, %s);", N.result, N.root, N.builder);
    out("exit_section_(%s, 0, %s, %s, %s, true, TRUE_CONDITION);", N.builder, N.marker, N.root, N.result);
    out("}");
    newLine();
    out("protected boolean parse_root_(%s %s, %s %s) {", shortET, N.root, shortPB, N.builder);
    out("return parse_root_(%s, %s, 0);", N.root, N.builder);
    out("}");
    newLine();
    out("static boolean parse_root_(%s %s, %s %s, int %s) {", shortET, N.root, shortPB, N.builder, N.level);
    if (extraRoots.isEmpty()) {
      out("return %s;", rootRule == null ? "false" : generateNodeCall(rootRule, null, myGrammarRoot).render(N));
    }
    else {
      boolean first = true;
      out("boolean %s;", N.result);
      for (BnfRule rule : extraRoots) {
        String elementType = getElementType(rule);
        out("%sif (%s == %s) {", first ? "" : "else ", N.root, elementType);
        String nodeCall = generateNodeCall(ObjectUtils.notNull(rootRule, rule), null, rule.getName()).render(N);
        out("%s = %s;", N.result, nodeCall);
        out("}");
        if (first) first = false;
      }
      out("else {");
      out("%s = %s;", N.result, rootRule == null ? "false" : generateNodeCall(rootRule, null, myGrammarRoot).render(N));
      out("}");
      out("return %s;", N.result);
    }
    out("}");
    newLine();
    if (generateExtendsSets) {
      out("public static final %s[] EXTENDS_SETS_ = new %s[] {", shortTS, shortTS);
      StringBuilder sb = new StringBuilder();
      for (Set<String> elementTypes : extendsSet) {
        int i = 0;
        for (String elementType : elementTypes) {
          if (i > 0) sb.append(i % 4 == 0 ? ",\n" : ", ");
          sb.append(elementType);
          i++;
        }
        out("create_token_set_(%s),", sb);
        sb.setLength(0);
      }
      out("};");
      newLine();
    }
  }