change dir of cellAttachmentRenderer (#157671)

* change dir of cellAttachmentRenderer

* add new directories to `.vscodeignore`

* add the .js directories back in...

* hopefully now understanding `.vscodeignore`

extensions/ipynb/notebook-src/cellAttachmentRenderer.ts

@@ -0,0 +1,47 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import type * as MarkdownIt from 'markdown-it';
+import type * as MarkdownItToken from 'markdown-it/lib/token';
+import type { RendererContext } from 'vscode-notebook-renderer';
+
+interface MarkdownItRenderer {
+	extendMarkdownIt(fn: (md: MarkdownIt) => void): void;
+}
+
+export async function activate(ctx: RendererContext<void>) {
+	const markdownItRenderer = (await ctx.getRenderer('vscode.markdown-it-renderer')) as MarkdownItRenderer | any;
+	if (!markdownItRenderer) {
+		throw new Error(`Could not load 'vscode.markdown-it-renderer'`);
+	}
+
+	markdownItRenderer.extendMarkdownIt((md: MarkdownIt) => {
+		const original = md.renderer.rules.image;
+		md.renderer.rules.image = (tokens: MarkdownItToken[], idx: number, options, env, self) => {
+			const token = tokens[idx];
+			const src = token.attrGet('src');
+			const attachments: Record<string, Record<string, string>> = env.outputItem.metadata.custom?.attachments;
+			if (attachments && src) {
+				const imageAttachment = attachments[src.replace('attachment:', '')];
+				if (imageAttachment) {
+					// objEntries will always be length 1, with objEntries[0] holding [0]=mime,[1]=b64
+					// if length = 0, something is wrong with the attachment, mime/b64 weren't copied over
+					const objEntries = Object.entries(imageAttachment);
+					if (objEntries.length) {
+						const [attachmentKey, attachmentVal] = objEntries[0];
+						const b64Markdown = 'data:' + attachmentKey + ';base64,' + attachmentVal;
+						token.attrSet('src', b64Markdown);
+					}
+				}
+			}
+
+			if (original) {
+				return original(tokens, idx, options, env, self);
+			} else {
+				return self.renderToken(tokens, idx, options);
+			}
+		};
+	});
+}