chore: fix tests, add new SEO tests

__mocks__/data/mock-post.ts

@@ -15,6 +15,9 @@ export const MockPost: PostInfo & RenderedPostInfo = {
   headingsWithId: [],
   wordCount: 10000,
   content: "",
+  translations: {
+    en: "English",
+  },
 };
 
 export const MockMultiAuthorPost: PostInfo & RenderedPostInfo = {
@@ -31,4 +34,46 @@ export const MockMultiAuthorPost: PostInfo & RenderedPostInfo = {
   headingsWithId: [],
   wordCount: 100000,
   content: "",
+  translations: {
+    en: "English",
+  },
+};
+
+export const MockMuliLanguagePost: PostInfo & RenderedPostInfo = {
+  excerpt:
+    "This would be a second auto generated excerpt of the post in particular",
+  title: "Another post title",
+  published: "10-20-2010",
+  tags: ["item1"],
+  description:
+    "This is another short description dunno why this would be this short",
+  authors: [MockUnicornTwo, MockUnicorn],
+  license: MockLicense,
+  slug: "this-other-post-name-here",
+  headingsWithId: [],
+  wordCount: 100000,
+  content: "",
+  translations: {
+    es: "Español",
+  },
+};
+
+export const MockCanonicalPost: PostInfo & RenderedPostInfo = {
+  excerpt:
+    "This would be a second auto generated excerpt of the post in particular",
+  title: "Another post title",
+  published: "10-20-2010",
+  originalLink: "https://google.com/",
+  tags: ["item1"],
+  description:
+    "This is another short description dunno why this would be this short",
+  authors: [MockUnicornTwo, MockUnicorn],
+  license: MockLicense,
+  slug: "this-other-post-name-here",
+  headingsWithId: [],
+  wordCount: 100000,
+  content: "",
+  translations: {
+    en: "English",
+  },
 };

src/components/seo.tsx

@@ -206,7 +206,7 @@ export const SEO: React.FC<PropsWithChildren<SEOProps>> = (props) => {
             rel="alternate"
             href={
               siteMetadata.siteUrl +
-              `${lang === "en" ? "" : "/"}${lang}` +
+              `${lang === "en" ? "" : "/"}${lang === "en" ? "" : lang}` +
               removePrefixLanguageFromPath(pathName || "")
             }
             hrefLang={lang}

src/page-components/blog-post/blog-post.test.tsx

@@ -1,10 +1,15 @@
-import React from "react";
+import React, { PropsWithChildren } from "react";
 import { fireEvent, render } from "@testing-library/react";
-import { siteMetadata } from "__mocks__/data/mock-site-metadata";
+import {
-import { MockMultiAuthorPost, MockPost } from "__mocks__/data/mock-post";
+  MockCanonicalPost,
+  MockMuliLanguagePost,
+  MockMultiAuthorPost,
+  MockPost,
+} from "__mocks__/data/mock-post";
 import BlogPostTemplate from "../../pages/[...postInfo]";
-import ReactDOMServer from "react-dom/server";
 import { RouterContext } from "next/dist/shared/lib/router-context";
+import { Languages } from "types/index";
+import { getAllByRel, getByProperty, getByRel } from "utils/tests";
 // import { axe } from "jest-axe";
 
 const getElement = ({
@@ -14,6 +19,7 @@ const getElement = ({
   slug = "/slug",
   postsDirectory = "/posts",
   seriesPosts = [],
+  lang = "en",
 }: {
   post: any;
   fn?: () => void;
@@ -21,6 +27,7 @@ const getElement = ({
   slug?: string;
   postsDirectory?: string;
   seriesPosts?: any[];
+  lang?: Languages;
 }) => (
   <RouterContext.Provider
     value={
@@ -39,6 +46,7 @@ const getElement = ({
       post={post}
       markdownHTML={markdownHTML}
       slug={slug}
+      lang={lang}
       postsDirectory={postsDirectory}
       seriesPosts={seriesPosts}
       suggestedPosts={[]}
@@ -74,7 +82,7 @@ test("Blog post page renders", async () => {
   expect(navigatePushFn).toHaveBeenCalledTimes(2);
 
   // Renders the post body properly
-  expect((await findByTestId("post-body-div")).innerHTML).toBe(
+  expect((await findByTestId("post-body-div")).innerHTML).toContain(
     "<div>Hey there</div>"
   );
 });
@@ -112,12 +120,71 @@ test("Blog post page handles two authors", async () => {
   expect(navigatePushFn).toHaveBeenCalledTimes(4);
 
   // Renders the post body properly
-  expect((await findByTestId("post-body-div")).innerHTML).toBe(
+  expect((await findByTestId("post-body-div")).innerHTML).toContain(
     "<div>Hello, friends</div>"
   );
 });
 
-test.todo("SEO should apply");
+/**
+ * Next head mocking to `head` element
+ *
+ * TODO: Turn this + queries into a library
+ */
+const mockDocument = document;
+
+jest.mock("next/head", () => {
+  const ReactDOM = require("react-dom");
+  return ({ children }: PropsWithChildren<unknown>) => {
+    return ReactDOM.createPortal(children, mockDocument.head);
+  };
+});
+
+test("SEO should show translation data", () => {
+  const navigatePushFn = jest.fn();
+
+  render(
+    getElement({
+      post: MockMuliLanguagePost,
+      fn: navigatePushFn,
+      markdownHTML: "Hello, friends",
+      lang: "en",
+    })
+  );
+
+  const alts = getAllByRel(document.head, "alternate");
+  expect(alts.length).toBe(2);
+  expect(alts[0]).toHaveProperty("hreflang", "x-default");
+  expect(alts[1]).toHaveProperty("hreflang", "es");
+
+  expect(getByProperty(document.head, "og:locale")).toHaveProperty(
+    "content",
+    "en"
+  );
+  expect(getByProperty(document.head, "og:locale:alternate")).toHaveProperty(
+    "content",
+    "es"
+  );
+});
+
+test("Canonical tags should show in SEO", () => {
+  const navigatePushFn = jest.fn();
+
+  render(
+    getElement({
+      post: MockCanonicalPost,
+      fn: navigatePushFn,
+      markdownHTML: "Hello, friends",
+      lang: "en",
+    })
+  );
+
+  expect(getByRel(document.head, "canonical")).toHaveProperty(
+    "href",
+    "https://google.com/"
+  );
+});
+
+test.todo("SEO Twitter");
 test.todo("Shows post footer image");
 
 // test.skip("Blog post page should not have axe errors", async () => {

src/page-components/blog-post/translations-header/translations-header.tsx

@@ -3,6 +3,7 @@ import { RenderedPostInfo } from "types/PostInfo";
 import { SlugPostInfo } from "constants/queries";
 import Link from "next/link";
 import { Languages } from "types/index";
+import { Fragment } from "react";
 
 interface TranslationsHeaderProps {
   post: SlugPostInfo & RenderedPostInfo;
@@ -14,12 +15,12 @@ export const TranslationsHeader = ({ post }: TranslationsHeaderProps) => {
       {(Object.keys(post.translations) as Languages[]).map((lang, i, arr) => {
         const langHref = lang === "en" ? "" : `${lang}/`;
         return (
-          <>
+          <Fragment key={lang}>
-            <Link key={lang} passHref href={`/${langHref}posts/${post.slug}`}>
+            <Link passHref href={`/${langHref}posts/${post.slug}`}>
               <a>{post.translations[lang]}</a>
             </Link>
             {i !== arr.length - 1 && <span>, </span>}
-          </>
+          </Fragment>
         );
       })}
     </div>

src/pages/[...postInfo].tsx

@@ -24,7 +24,7 @@ import { MailingList } from "components/mailing-list";
 
 import GitHubIcon from "assets/icons/github.svg";
 import CommentsIcon from "assets/icons/message.svg";
-import { useContext, useEffect, useState } from "react";
+import { useContext, useEffect, useMemo, useState } from "react";
 import { ThemeContext } from "constants/theme-context";
 import { siteMetadata } from "constants/site-config";
 import "react-medium-image-zoom/dist/styles.css";
@@ -101,6 +101,19 @@ const Post = ({
 
   const GHLink = `https://github.com/${siteMetadata.repoPath}/tree/master${siteMetadata.relativeToPosts}/${slug}/index.md`;
 
+  const langData = useMemo(() => {
+    const otherLangs = post.translations
+      ? (Object.keys(post.translations).filter(
+          (t) => t !== lang
+        ) as Languages[])
+      : [];
+
+    return {
+      otherLangs,
+      currentLang: lang,
+    };
+  }, [lang, post.translations]);
+
   return (
     <>
       <SEO
@@ -113,12 +126,7 @@ const Post = ({
         type="article"
         pathName={router.asPath}
         canonical={post.originalLink}
-        langData={{
+        langData={langData}
-          currentLang: lang,
-          otherLangs: post.translations
-            ? (Object.keys(post.translations) as Languages[])
-            : [],
-        }}
       />
       <article>
         <BlogPostLayout

src/types/PostInfo.ts

@@ -18,7 +18,7 @@ export interface PostInfo {
   originalLink?: string;
   content: string;
   tags: string[];
-  translations: Record<Languages, string>;
+  translations: Partial<Record<Languages, string>>;
 }
 
 export interface RenderedPostInfo {

src/utils/queries/index.ts

@@ -0,0 +1,3 @@
+export * from "./name";
+export * from "./property";
+export * from "./rel";

src/utils/queries/name.ts

@@ -0,0 +1,34 @@
+import { wrapAllByQueryWithSuggestion } from "@testing-library/dom/dist/query-helpers";
+import { checkContainerType } from "@testing-library/dom/dist/helpers";
+import {
+  AllByBoundAttribute,
+  GetErrorFunction,
+  queryAllByAttribute,
+  buildQueries,
+} from "@testing-library/dom";
+
+const queryAllByName: AllByBoundAttribute = (...args) => {
+  checkContainerType(args[0]);
+  return queryAllByAttribute("name", ...args);
+};
+const getMultipleError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Found multiple elements with the name text of: ${text}`;
+const getMissingError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Unable to find an element with the name text of: ${text}`;
+
+const queryAllByNameWithSuggestions = wrapAllByQueryWithSuggestion<
+  // @ts-expect-error -- See `wrapAllByQueryWithSuggestion` Argument constraint comment
+  [name: Matcher, options?: MatcherOptions]
+>(queryAllByName, queryAllByName.name, "queryAll");
+
+const [queryByName, getAllByName, getByName, findAllByName, findByName] =
+  buildQueries(queryAllByName, getMultipleError, getMissingError);
+
+export {
+  queryByName,
+  queryAllByNameWithSuggestions as queryAllByName,
+  getByName,
+  getAllByName,
+  findAllByName,
+  findByName,
+};

src/utils/queries/property.ts

@@ -0,0 +1,39 @@
+import { wrapAllByQueryWithSuggestion } from "@testing-library/dom/dist/query-helpers";
+import { checkContainerType } from "@testing-library/dom/dist/helpers";
+import {
+  AllByBoundAttribute,
+  GetErrorFunction,
+  queryAllByAttribute,
+  buildQueries,
+} from "@testing-library/dom";
+
+const queryAllByProperty: AllByBoundAttribute = (...args) => {
+  checkContainerType(args[0]);
+  return queryAllByAttribute("property", ...args);
+};
+const getMultipleError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Found multiple elements with the property text of: ${text}`;
+const getMissingError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Unable to find an element with the property text of: ${text}`;
+
+const queryAllByPropertyWithSuggestions = wrapAllByQueryWithSuggestion<
+  // @ts-expect-error -- See `wrapAllByQueryWithSuggestion` Argument constraint comment
+  [property: Matcher, options?: MatcherOptions]
+>(queryAllByProperty, queryAllByProperty.name, "queryAll");
+
+const [
+  queryByProperty,
+  getAllByProperty,
+  getByProperty,
+  findAllByProperty,
+  findByProperty,
+] = buildQueries(queryAllByProperty, getMultipleError, getMissingError);
+
+export {
+  queryByProperty,
+  queryAllByPropertyWithSuggestions as queryAllByProperty,
+  getByProperty,
+  getAllByProperty,
+  findAllByProperty,
+  findByProperty,
+};

src/utils/queries/rel.ts

@@ -0,0 +1,36 @@
+import { wrapAllByQueryWithSuggestion } from "@testing-library/dom/dist/query-helpers";
+import { checkContainerType } from "@testing-library/dom/dist/helpers";
+import {
+  AllByBoundAttribute,
+  GetErrorFunction,
+  queryAllByAttribute,
+  buildQueries,
+  Matcher,
+  MatcherOptions,
+} from "@testing-library/dom";
+
+const queryAllByRel: AllByBoundAttribute = (...args) => {
+  checkContainerType(args[0]);
+  return queryAllByAttribute("rel", ...args);
+};
+const getMultipleError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Found multiple elements with the rel text of: ${text}`;
+const getMissingError: GetErrorFunction<[unknown]> = (c, text) =>
+  `Unable to find an element with the rel text of: ${text}`;
+
+const queryAllByRelWithSuggestions = wrapAllByQueryWithSuggestion<
+  // @ts-expect-error -- See `wrapAllByQueryWithSuggestion` Argument constraint comment
+  [rel: Matcher, options?: MatcherOptions]
+>(queryAllByRel, queryAllByRel.name, "queryAll");
+
+const [queryByRel, getAllByRel, getByRel, findAllByRel, findByRel] =
+  buildQueries(queryAllByRel, getMultipleError, getMissingError);
+
+export {
+  queryByRel,
+  queryAllByRelWithSuggestions as queryAllByRel,
+  getByRel,
+  getAllByRel,
+  findAllByRel,
+  findByRel,
+};

src/utils/queries/types.d.ts

@@ -0,0 +1,17 @@
+declare module "@testing-library/dom/dist/query-helpers" {
+  import { Variant, WithSuggest } from "@testing-library/dom";
+  declare const wrapAllByQueryWithSuggestion: <
+    Arguments extends [...unknown[], WithSuggest]
+  >(
+    query: (container: HTMLElement, ...args: Arguments) => HTMLElement[],
+    queryAllByName: string,
+    variant: Variant
+  ) => (container: HTMLElement, ...args: Arguments) => HTMLElement[];
+
+  export { wrapAllByQueryWithSuggestion };
+}
+
+declare module "@testing-library/dom/dist/helpers" {
+  declare const checkContainerType: (...props: any[]) => any;
+  export { checkContainerType };
+}

src/utils/tests.ts

@@ -0,0 +1,2 @@
+// TODO: Turn this into a library
+export * from "./queries";