no-doubled-conjunction.js

// LICENSE : MIT
"use strict";
import {RuleHelper} from "textlint-rule-helper";
import {getTokenizer} from "kuromojin";
import {split as splitSentences, Syntax as SentenceSyntax} from "sentence-splitter";
import StringSource from "textlint-util-to-string";

/*
    1. Paragraph Node -> text
    2. text -> sentences
    3. tokenize sentence
    4. report error if found word that match the rule.

    TODO: need abstraction
 */
export default function (context, options = {}) {
    const helper = new RuleHelper(context);
    const {Syntax, report, getSource, RuleError} = context;
    return {
        [Syntax.Paragraph](node){
            if (helper.isChildNode(node, [Syntax.Link, Syntax.Image, Syntax.BlockQuote, Syntax.Emphasis])) {
                return;
            }
            const source = new StringSource(node);
            const text = source.toString();
            const isSentenceNode = (node) => node.type === SentenceSyntax.Sentence;
            let sentences = splitSentences(text, {
                charRegExp: /[.．。\?\!？！]/
            }).filter(isSentenceNode);
            // if not have a sentence, early return
            // It is for avoiding error of emptyArray.reduce().
            if(sentences.length === 0) {
                return;
            }
            return getTokenizer().then(tokenizer => {
              const selectConjenction = (sentence) => {
                let tokens = tokenizer.tokenizeForSentence(sentence.raw);
                let conjunctionTokens = tokens.filter((token) => token.pos === "接続詞");
                return [sentence, conjunctionTokens];
              };
              let prev_token = null;
              sentences.map(selectConjenction).reduce((prev, current) => {
                let token = prev_token;
                let [sentence, current_tokens] = current;
                let [prev_sentence, prev_tokens] = prev;
                if (prev_tokens && prev_tokens.length > 0) {
                  token = prev_tokens[0];
                }
                if (current_tokens.length > 0) {
                  if (token && current_tokens[0].surface_form === token.surface_form) {
                    let originalIndex = source.originalIndexFromPosition({
                      line: sentence.loc.start.line,
                      column: sentence.loc.start.column + (current_tokens[0].word_position - 1)
                    });
                    // padding position
                    var padding = {
                        index: originalIndex
                    };
                    report(node, new RuleError(`同じ接続詞が連続して使われています。`, padding));
                  }
                }
                prev_token = token;
                return current;
              });
            });
        }
    }
};