Add steps component

package.json

@@ -43,6 +43,7 @@
     "query-string": "^7.1.1",
     "react-instantsearch-hooks-web": "^6.38.1",
     "react-mailchimp-subscribe": "^2.1.3",
+    "rehype-format": "^5.0.0",
     "rehype-katex": "^7.0.0",
     "rehype-mermaidjs": "^1.0.1",
     "remark-gfm": "^4.0.0",

src/components/Steps/Steps.astro

@@ -0,0 +1,91 @@
+---
+import { processSteps } from "./rehype-steps"
+
+const content = await Astro.slots.render("default")
+const { html } = processSteps(content)
+---
+
+<Fragment set:html={html} />
+
+<style is:global>
+  .sl-steps {
+    --bullet-size: calc(1.75 * 1rem);
+    --bullet-margin: 0.375rem;
+
+    list-style: none;
+    counter-reset: steps-counter var(--sl-steps-start, 0);
+    padding-inline-start: 0;
+  }
+
+  .sl-steps > li {
+    counter-increment: steps-counter;
+    position: relative;
+    padding-inline-start: calc(var(--bullet-size) + 1rem);
+    /* HACK: Keeps any `margin-bottom` inside the `<li>`’s padding box to avoid gaps in the hairline border. */
+    padding-bottom: 1px;
+    /* Prevent bullets from touching in short list items. */
+    min-height: calc(var(--bullet-size) + var(--bullet-margin));
+  }
+  .sl-steps > li + li {
+    /* Remove margin between steps. */
+    margin-top: 0;
+  }
+
+  /* Custom list marker element. */
+  .sl-steps > li::before {
+    content: counter(steps-counter);
+    position: absolute;
+    top: 0;
+    inset-inline-start: 0;
+    width: var(--bullet-size);
+    height: var(--bullet-size);
+    line-height: var(--bullet-size);
+
+    font-size: var(--sl-text-xs);
+    font-weight: 600;
+    text-align: center;
+    color: hsl(0, 0%, 100%);
+    background-color: hsl(224, 14%, 16%);
+    border-radius: 99rem;
+    box-shadow: inset 0 0 0 1px hsl(224, 10%, 23%);
+  }
+
+  /* Vertical guideline linking list numbers. */
+  .sl-steps > li:not(:last-of-type)::after {
+    --guide-width: 1px;
+    content: "";
+    position: absolute;
+    top: calc(var(--bullet-size) + var(--bullet-margin));
+    bottom: var(--bullet-margin);
+    inset-inline-start: calc((var(--bullet-size) - var(--guide-width)) / 2);
+    width: var(--guide-width);
+    background-color: #24262e;
+  }
+
+  /* Adjust first item inside a step so that it aligns vertically with the number
+			even if using a larger font size (e.g. a heading) */
+  .sl-steps > li > :first-child {
+    /*
+		The `lh` unit is not yet supported by all browsers in our support matrix
+		— see https://caniuse.com/mdn-css_types_length_lh
+		In unsupported browsers we approximate this using our known line-heights.
+		*/
+    --lh: calc(1em * var(--sl-line-height));
+    --shift-y: calc(0.5 * (var(--bullet-size) - var(--lh)));
+    transform: translateY(var(--shift-y));
+    margin-bottom: var(--shift-y);
+  }
+  .sl-steps > li > :first-child:where(h1, h2, h3, h4, h5, h6) {
+    --lh: calc(1em * var(--sl-line-height-headings));
+  }
+  @supports (--prop: 1lh) {
+    .sl-steps > li > :first-child {
+      --lh: 1lh;
+    }
+  }
+
+  .sl-steps .expressive-code {
+    margin-top: 1rem;
+    margin-bottom: 1.25rem;
+  }
+</style>

src/components/Steps/rehype-steps.ts

@@ -0,0 +1,44 @@
+import type { Element, Root } from "hast"
+import { rehype } from "rehype"
+import rehypeFormat from "rehype-format"
+import type { VFile } from "vfile"
+
+const prettyPrintProcessor = rehype().data("settings", { fragment: true }).use(rehypeFormat)
+const prettyPrintHtml = (html: string) => prettyPrintProcessor.processSync({ value: html }).toString()
+
+const stepsProcessor = rehype()
+  .data("settings", { fragment: true })
+  .use(function steps() {
+    return (tree: Root, vfile: VFile) => {
+      const rootElements = tree.children.filter((item): item is Element => item.type === "element")
+      const [rootElement] = rootElements
+
+      // Ensure `role="list"` is set on the ordered list.
+      // We use `list-style: none` in the styles for this component and need to ensure the list
+      // retains its semantics in Safari, which will remove them otherwise.
+      rootElement.properties.role = "list"
+      // Add the required CSS class name, preserving existing classes if present.
+      if (!Array.isArray(rootElement.properties.className)) {
+        rootElement.properties.className = ["sl-steps"]
+      } else {
+        rootElement.properties.className.push("sl-steps")
+      }
+
+      // Add the `start` attribute as a CSS custom property so we can use it as the starting index
+      // of the steps custom counter.
+      if (typeof rootElement.properties.start === "number") {
+        const styles = [`--sl-steps-start: ${rootElement.properties.start - 1}`]
+        if (rootElement.properties.style) styles.push(String(rootElement.properties.style))
+        rootElement.properties.style = styles.join(";")
+      }
+    }
+  })
+
+/**
+ * Process steps children: validates the HTML and adds `role="list"` to the ordered list.
+ * @param html Inner HTML passed to the `<Steps>` component.
+ */
+export const processSteps = (html: string | undefined) => {
+  const file = stepsProcessor.processSync({ value: html })
+  return { html: file.toString() }
+}

src/content/docs/en/article-components.mdx

@@ -15,6 +15,7 @@ import Aside from "../../../components/Aside.astro"
 import MarkmapView from "../../../components/MarkmapView/index.astro"
 import RPCTable from "../../../components/RPCTable/RPCTable.astro"
 import { Tabs, TabsContent } from "../../../components/Tabs"
+import Steps from '../../../components/Steps/Steps.astro';
 
 This is body text right under the article title. It typically is just paragraph text that's pretty straightforward. Then there's **bold text**, and _italic text_, and **_bold-italic text_**, and `inline-code` and **`bold inline code`** and even _`italic inline code`_ and **_`bold italic inline code`_**. And of course don't forget [links](#), and [**bold links**](#), and [_italic links_](#), and [**_bold-italic links_**](#).
 
@@ -38,6 +39,21 @@ What else do we have?
 
 ##### H5 Heading
 
+### Steps
+
+
+<Steps>
+
+1. Import the component into your MDX file:
+
+   ```js
+   import { Steps } from '@astrojs/starlight/components';
+   ```
+
+2. Wrap `<Steps>` around your ordered list items.
+
+</Steps>
+
 Let's see a horizontal rule.
 
 ---