How to use

getTokenStart

method

in

com.intellij.lexer.Lexer

public int getTokenStart() {
  return lexer().getTokenStart();
}

private void restoreElixirPosition(@Nullable LexerPosition elixirPosition) {
  if (elixirPosition != null) {
    elixirLexer.start(getBufferSequence(), eexLexer.getTokenStart(), eexLexer.getTokenEnd());
    elixirLexer.restore(elixirPosition);
  }
}

public void advance() {
  if (eexLexer.getTokenType() == ELIXIR) {
    elixirLexer.advance();
    if (elixirLexer.getTokenType() == null) {
      eexLexer.advance();
    }
  } else {
    eexLexer.advance();
    if (eexLexer.getTokenType() == ELIXIR) {
      // start automatically does equivalent of `advance` since `elixirLexer` is also a look-ahead lexer
      elixirLexer.start(getBufferSequence(), eexLexer.getTokenStart(), eexLexer.getTokenEnd());
    }
  }
}

@Override
public int getTokenStart() {
  int tokenStart = myDelegate.getTokenStart();
  if (!afterPrefix && tokenStart == 0) {
    return 0;
  }
  if (afterEOF) {
    return prefix.length() + suffix.length() + tokenStart;
  }
  return prefix.length() + tokenStart;
}

 private void lexToken(Lexer lexer) {
  myTokenType = lexer.getTokenType();
  if (myTokenType == LEFT_BRACE_CODE_START) {
   myTokenType = LEFT_BRACE;
  }
  myTokenStart = lexer.getTokenStart();
  myState = lexer.getState();
  myTokenEnd = lexer.getTokenEnd();
  lexer.advance();
 }
}

final String tokenText = lexer.getTokenText();
int tokenStart = lexer.getTokenStart();
int tokenEnd = lexer.getTokenEnd();
int realLength = tokenEnd - tokenStart;

@Test
public void testEmptyDelegate() throws Exception {
  String prefix = "prefix ";
  String suffix = " suffix";
  PrefixSuffixAddingLexer lexer = new PrefixSuffixAddingLexer(new EmptyLexer(), prefix, BashTokenTypes.STRING2, suffix, BashTokenTypes.STRING2);
  assertPosition(lexer, 0, prefix.length(), 0, BashTokenTypes.STRING2, prefix);
  lexer.advance();
  assertPosition(lexer, prefix.length(), prefix.length() + suffix.length(), 0, BashTokenTypes.STRING2, suffix);
  //after the first advance the delegate must still be at initial position
  Assert.assertEquals(0, lexer.getDelegate().getTokenStart());
  lexer.advance();
  Assert.assertNull(lexer.getTokenType());
  assertPosition(lexer, prefix.length() + suffix.length(), prefix.length() + suffix.length(), 0, null, "");
}