question: private static List < TextRange > addPreviousComma ( PsiElement e , int cursorOffset ) { PsiElement prevSibling = e . getPrevSibling ( ) ; TextRange textRange = e . getTextRange ( ) ; TextRange offsetRange = null ; if ( prevSibling != null ) { if ( prevSibling instanceof PsiWhiteSpace ) { PsiElement prevCommaSibling = prevSibling . getPrevSibling ( ) ; if ( prevCommaSibling != null ) { ASTNode node = prevCommaSibling . getNode ( ) ; if ( node != null ) { IElementType commaType = node . getElementType ( ) ; if ( commaType == PyTokenTypes . COMMA ) { offsetRange = new TextRange ( textRange . getStartOffset ( ) - 2 , textRange . getEndOffset ( ) ) ; if ( offsetRange . contains ( cursorOffset ) && offsetRange . getLength ( ) > 1 ) { return Collections . singletonList ( offsetRange ) ; } } } } } else { ASTNode node = prevSibling . getNode ( ) ; if ( node != null ) { IElementType commaType = node . getElementType ( ) ; if ( commaType == PyTokenTypes . COMMA ) { offsetRange = new TextRange ( textRange . getStartOffset ( ) - 1 , textRange . getEndOffset ( ) ) ; } } } if ( offsetRange != null ) { if ( offsetRange . contains ( cursorOffset ) && offsetRange . getLength ( ) > 1 ) { return Collections . singletonList ( offsetRange ) ; } } } return Collections . emptyList ( ) ; }
target:  adds previous comma and whitespace to result text range