fix smart quotes (#770)

fix smart quotes - closes #470

Author: Rich-Harris

packages/site-kit/src/lib/markdown/renderer.ts

@@ -281,34 +281,33 @@ export async function render_content_markdown(
 				snippets.save(token.text, html);
 			}
 
-			// ensure that `foo`/`bar` is transformed to `foo` / `bar`
-			// https://github.com/sveltejs/svelte.dev/pull/577
-			const slash_index =
-				// @ts-expect-error
-				token.tokens?.findIndex((token) => token.type === 'text' && token.text === '/') ?? -1;
-
-			if (slash_index !== -1) {
-				// @ts-expect-error
-				const before = token.tokens[slash_index - 1];
-				// @ts-expect-error
-				const after = token.tokens[slash_index + 1];
-
-				if (before?.type === 'codespan' && after?.type === 'codespan') {
-					// @ts-expect-error
-					token.tokens[slash_index].raw = token.tokens[slash_index].text = ' / ';
+			const tokens = 'tokens' in token ? token.tokens : undefined;
+
+			if (tokens) {
+				// ensure that `foo`/`bar` is transformed to `foo` / `bar`
+				// https://github.com/sveltejs/svelte.dev/pull/577
+				const slash_index =
+					tokens.findIndex((token) => token.type === 'text' && token.text === '/') ?? -1;
+
+				if (slash_index !== -1) {
+					const before = tokens[slash_index - 1];
+					const after = tokens[slash_index + 1];
+
+					if (before?.type === 'codespan' && after?.type === 'codespan') {
+						// @ts-expect-error
+						tokens[slash_index].raw = tokens[slash_index].text = ' / ';
+					}
 				}
-			}
-		},
-		text(token) {
-			// @ts-expect-error I think this is a bug in marked — some text tokens have children,
-			// but that's not reflected in the types. In these cases we can't just use `token.tokens`
-			// because that will result in e.g. `<code>` elements not being generated
-			if (token.tokens) {
-				// @ts-expect-error
-				return this.parser!.parseInline(token.tokens);
-			}
 
-			return smart_quotes(token.text, true);
+				// smart quotes
+				for (let i = 0; i < tokens.length; i += 1) {
+					const token = tokens[i];
+
+					if (token.type === 'text') {
+						token.text = smart_quotes(token.text, { first: i === 0, html: true });
+					}
+				}
+			}
 		},
 		heading({ tokens, depth }) {
 			const text = this.parser!.parseInline(tokens);

packages/site-kit/src/lib/markdown/utils.ts

@@ -42,16 +42,18 @@ export const slugify = (str: string) => {
 		.replace(/-$/, '');
 };
 
-export function smart_quotes(str: string, html: boolean = false) {
+export function smart_quotes(
+	str: string,
+	{ first = true, html = false }: { first?: boolean; html?: boolean } = {}
+) {
 	// replace dumb quotes with smart quotes. This isn't a perfect algorithm — it
 	// wouldn't correctly handle `That '70s show` or `My country 'tis of thee`
 	// but a) it's very unlikely they'll occur in our docs, and
 	// b) they can be dealt with manually
 	return str.replace(
 		html ? /(.|^)('|")(.|$)/g : /(.|^)('|")(.|$)/g,
 		(m, before, quote, after) => {
-			const trimmed = before.trim();
-			const left = trimmed === '' || trimmed === '(';
+			const left = (first && before === '') || [' ', '\n', '('].includes(before);
 			let replacement = '';
 
 			if (html) {