UNPKG

yoastseo

Version:

Yoast client-side content analysis

181 lines (170 loc) 9 kB
"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.default = void 0; var _i18n = require("@wordpress/i18n"); var _lodash = require("lodash"); var _assessment = _interopRequireDefault(require("../assessment")); var _inRange = require("../../helpers/assessments/inRange.js"); var _shortlinker = require("../../../helpers/shortlinker"); var _AssessmentResult = _interopRequireDefault(require("../../../values/AssessmentResult")); function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; } /** * Represents the assessment that checks if there are keyphrase or synonyms in the alt attributes of images. */ class KeyphraseInImagesAssessment extends _assessment.default { /** * Sets the identifier and the config. * * @param {object} config The configuration to use. * * @returns {void} */ constructor(config = {}) { super(); const defaultConfig = { parameters: { lowerBoundary: 0.3, upperBoundary: 0.75 }, scores: { withAltGoodNumberOfKeywordMatches: 9, withAltTooFewKeywordMatches: 6, withAltTooManyKeywordMatches: 6, withAltNonKeyword: 6, withAlt: 6, noAlt: 6 }, urlTitle: (0, _shortlinker.createAnchorOpeningTag)("https://yoa.st/4f7"), urlCallToAction: (0, _shortlinker.createAnchorOpeningTag)("https://yoa.st/4f6") }; this.identifier = "imageKeyphrase"; this._config = (0, _lodash.merge)(defaultConfig, config); } /** * Execute the Assessment and return a result. * * @param {Paper} paper The Paper object to assess. * @param {Researcher} researcher The Researcher object containing all available researches. * * @returns {AssessmentResult} The result of the assessment, containing both a score and a descriptive text. */ getResult(paper, researcher) { this.imageCount = researcher.getResearch("imageCount"); this.altProperties = researcher.getResearch("altTagCount"); this._minNumberOfKeywordMatches = Math.ceil(this.imageCount * this._config.parameters.lowerBoundary); this._maxNumberOfKeywordMatches = Math.floor(this.imageCount * this._config.parameters.upperBoundary); const calculatedScore = this.calculateResult(); const assessmentResult = new _AssessmentResult.default(); assessmentResult.setScore(calculatedScore.score); assessmentResult.setText(calculatedScore.resultText); return assessmentResult; } /** * Checks whether the paper has text with at least 1 image. * * @param {Paper} paper The paper to use for the assessment. * @param {Researcher} researcher The Researcher object containing all available researches. * * @returns {boolean} True when there is text. */ isApplicable(paper, researcher) { this.imageCount = researcher.getResearch("imageCount"); return paper.hasText() && this.imageCount > 0; } /** * Checks whether there are too few alt tags with keywords. This check is applicable when there are * 5 or more images. * * @returns {boolean} Returns true if there are at least 5 images and the number of alt tags * with keywords is under the specified recommended minimum. */ hasTooFewMatches() { return this.imageCount > 4 && this.altProperties.withAltKeyword > 0 && this.altProperties.withAltKeyword < this._minNumberOfKeywordMatches; } /** * Checks whether there is a sufficient number of alt tags with keywords. There are different recommended * ranges for less than 5 keywords, exactly 5 keywords, and more than 5 keywords. * * @returns {boolean} Returns true if the number of alt tags with keywords is within the recommended range. */ hasGoodNumberOfMatches() { return this.imageCount < 5 && this.altProperties.withAltKeyword > 0 || this.imageCount === 5 && (0, _inRange.inRangeStartEndInclusive)(this.altProperties.withAltKeyword, 2, 4) || this.imageCount > 4 && (0, _inRange.inRangeStartEndInclusive)(this.altProperties.withAltKeyword, this._minNumberOfKeywordMatches, this._maxNumberOfKeywordMatches); } /** * Checks whether there is a sufficient number of alt tags with keywords. This check is applicable when there are * 5 or more images. * * @returns {boolean} Returns true if there are at least 5 images and the number of alt tags with keywords * is above the recommended range. */ hasTooManyMatches() { return this.imageCount > 4 && this.altProperties.withAltKeyword > this._maxNumberOfKeywordMatches; } /** * Calculate the result based on the current image count and current image alt-tag count. * * @returns {Object} The calculated result. */ calculateResult() { // Has alt-tags, but no keyword is set. if (this.altProperties.withAlt > 0) { return { score: this._config.scores.withAlt, resultText: (0, _i18n.sprintf)(/* translators: %1$s and %2$s expand to links on yoast.com, %3$s expands to the anchor end tag */ (0, _i18n.__)("%1$sImage Keyphrase%3$s: Images on this page have alt attributes, but you have not set your keyphrase. %2$sFix that%3$s!", "wordpress-seo"), this._config.urlTitle, this._config.urlCallToAction, "</a>") }; } // Has alt-tags, but no keywords while a keyword is set. if (this.altProperties.withAltNonKeyword > 0 && this.altProperties.withAltKeyword === 0) { return { score: this._config.scores.withAltNonKeyword, resultText: (0, _i18n.sprintf)(/* translators: %1$s and %2$s expand to links on yoast.com, %3$s expands to the anchor end tag */ (0, _i18n.__)("%1$sImage Keyphrase%3$s: Images on this page do not have alt attributes with at least half of the words from your keyphrase. %2$sFix that%3$s!", "wordpress-seo"), this._config.urlTitle, this._config.urlCallToAction, "</a>") }; } // Image count ≥5, has alt-tags with too few keywords. if (this.hasTooFewMatches()) { return { score: this._config.scores.withAltTooFewKeywordMatches, resultText: (0, _i18n.sprintf)( /* translators: %1$d expands to the number of images containing an alt attribute with the keyword, * %2$d expands to the total number of images, %3$s and %4$s expand to links on yoast.com, * %5$s expands to the anchor end tag. */ (0, _i18n._n)("%3$sImage Keyphrase%5$s: Out of %2$d images on this page, only %1$d has an alt attribute that reflects the topic of your text. %4$sAdd your keyphrase or synonyms to the alt tags of more relevant images%5$s!", "%3$sImage Keyphrase%5$s: Out of %2$d images on this page, only %1$d have alt attributes that reflect the topic of your text. %4$sAdd your keyphrase or synonyms to the alt tags of more relevant images%5$s!", this.altProperties.withAltKeyword, "wordpress-seo"), this.altProperties.withAltKeyword, this.imageCount, this._config.urlTitle, this._config.urlCallToAction, "</a>") }; } /* * The hasGoodNumberOfMatches check needs to be made before the check for too many matches because of the special rule for * exactly 5 matches. */ if (this.hasGoodNumberOfMatches()) { return { score: this._config.scores.withAltGoodNumberOfKeywordMatches, resultText: (0, _i18n.sprintf)( /* translators: %1$s expands to a link on yoast.com, * %2$s expands to the anchor end tag. */ (0, _i18n.__)("%1$sImage Keyphrase%2$s: Good job!", "wordpress-seo"), this._config.urlTitle, "</a>") }; } if (this.hasTooManyMatches()) { return { score: this._config.scores.withAltTooManyKeywordMatches, resultText: (0, _i18n.sprintf)( /* translators: %1$d expands to the number of images containing an alt attribute with the keyword, * %2$d expands to the total number of images, %3$s and %4$s expand to a link on yoast.com, * %5$s expands to the anchor end tag. */ (0, _i18n.__)("%3$sImage Keyphrase%5$s: Out of %2$d images on this page, %1$d have alt attributes with words from your keyphrase or synonyms. That's a bit much. %4$sOnly include the keyphrase or its synonyms when it really fits the image%5$s.", "wordpress-seo"), this.altProperties.withAltKeyword, this.imageCount, this._config.urlTitle, this._config.urlCallToAction, "</a>") }; } // Images, but no alt tags. return { score: this._config.scores.noAlt, resultText: (0, _i18n.sprintf)(/* translators: %1$s and %2$s expand to links on yoast.com, %3$s expands to the anchor end tag */ (0, _i18n.__)("%1$sImage Keyphrase%3$s: Images on this page do not have alt attributes that reflect the topic of your text. %2$sAdd your keyphrase or synonyms to the alt tags of relevant images%3$s!", "wordpress-seo"), this._config.urlTitle, this._config.urlCallToAction, "</a>") }; } } exports.default = KeyphraseInImagesAssessment; //# sourceMappingURL=KeyphraseInImageTextAssessment.js.map