Emdash source with visual editor image upload fix

Fixes:
1. media.ts: wrap placeholder generation in try-catch
2. toolbar.ts: check r.ok, display error message in popover

packages/core/tests/unit/media/placeholder.test.ts

@@ -0,0 +1,143 @@
+import { describe, it, expect } from "vitest";
+
+import { generatePlaceholder } from "../../../src/media/placeholder.js";
+
+const CSS_RGB_PATTERN = /^rgb\(\d+,\s?\d+,\s?\d+\)$/;
+
+/** Minimal 4x4 solid red JPEG */
+const JPEG_4x4 = Buffer.from(
+	"/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAMCAgICAgMCAgIDAwMDBAYEBAQEBAgGBgUGCQgKCgkICQkKDA8MCgsOCwkJDRENDg8QEBEQCgwSExIQEw8QEBD/2wBDAQMDAwQDBAgEBAgQCwkLEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBAQEBD/wAARCAAEAAQDAREAAhEBAxEB/8QAFAABAAAAAAAAAAAAAAAAAAAACP/EABQQAQAAAAAAAAAAAAAAAAAAAAD/xAAVAQEBAAAAAAAAAAAAAAAAAAAHCf/EABQRAQAAAAAAAAAAAAAAAAAAAAD/2gAMAwEAAhEDEQA/ADoDFU3/2Q==",
+	"base64",
+);
+
+/** Minimal 4x4 solid red PNG */
+const PNG_4x4 = Buffer.from(
+	"iVBORw0KGgoAAAANSUhEUgAAAAQAAAAEAQMAAACTPww9AAAAIGNIUk0AAHomAACAhAAA+gAAAIDoAAB1MAAA6mAAADqYAAAXcJy6UTwAAAAGUExURf8AAP///0EdNBEAAAABYktHRAH/Ai3eAAAAB3RJTUUH6gIcETMVn1ZhnwAAACV0RVh0ZGF0ZTpjcmVhdGUAMjAyNi0wMi0yOFQxNzo1MToyMCswMDowMJE6EiQAAAAldEVYdGRhdGU6bW9kaWZ5ADIwMjYtMDItMjhUMTc6NTE6MjArMDA6MDDgZ6qYAAAAKHRFWHRkYXRlOnRpbWVzdGFtcAAyMDI2LTAyLTI4VDE3OjUxOjIwKzAwOjAwt3KLRwAAAAtJREFUCNdjYIAAAAAIAAEvIN0xAAAAAElFTkSuQmCC",
+	"base64",
+);
+
+/** 100x100 solid blue JPEG (for downsampling test) */
+const JPEG_100x100 = Buffer.from(
+	"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",
+	"base64",
+);
+
+describe("generatePlaceholder", () => {
+	it("generates blurhash and dominantColor from a JPEG", async () => {
+		const result = await generatePlaceholder(new Uint8Array(JPEG_4x4), "image/jpeg");
+
+		expect(result).not.toBeNull();
+		expect(result!.blurhash).toBeTruthy();
+		expect(typeof result!.blurhash).toBe("string");
+		expect(result!.dominantColor).toBeTruthy();
+		expect(typeof result!.dominantColor).toBe("string");
+	});
+
+	it("generates blurhash and dominantColor from a PNG", async () => {
+		const result = await generatePlaceholder(new Uint8Array(PNG_4x4), "image/png");
+
+		expect(result).not.toBeNull();
+		expect(result!.blurhash).toBeTruthy();
+		expect(result!.dominantColor).toBeTruthy();
+	});
+
+	it("returns a valid CSS color string for dominantColor", async () => {
+		const result = await generatePlaceholder(new Uint8Array(JPEG_4x4), "image/jpeg");
+
+		expect(result).not.toBeNull();
+		// Should be rgb() format from rgbColorToCssString
+		expect(result!.dominantColor).toMatch(CSS_RGB_PATTERN);
+	});
+
+	it("returns null for non-image MIME types", async () => {
+		const buffer = new Uint8Array([0, 1, 2, 3]);
+		const result = await generatePlaceholder(buffer, "application/pdf");
+
+		expect(result).toBeNull();
+	});
+
+	it("returns null for unsupported image types", async () => {
+		const buffer = new Uint8Array([0, 1, 2, 3]);
+		const result = await generatePlaceholder(buffer, "image/svg+xml");
+
+		expect(result).toBeNull();
+	});
+
+	it("returns null for corrupt image data", async () => {
+		const buffer = new Uint8Array([0xff, 0xd8, 0xff, 0xe0, 0, 0, 0]);
+		const result = await generatePlaceholder(buffer, "image/jpeg");
+
+		expect(result).toBeNull();
+	});
+
+	it("handles larger images by downsampling", async () => {
+		const result = await generatePlaceholder(new Uint8Array(JPEG_100x100), "image/jpeg");
+
+		expect(result).not.toBeNull();
+		expect(result!.blurhash).toBeTruthy();
+		// Blurhash string length should be reasonable (not huge from 100x100)
+		expect(result!.blurhash.length).toBeLessThan(50);
+	});
+
+	it("returns null when image dimensions from headers exceed memory budget", async () => {
+		// Minimal valid JPEG with SOF0 declaring 5000x4000 dimensions.
+		// SOF0 marker (FFC0) stores height (2 bytes) then width (2 bytes).
+		// 5000×4000×4 = 80 MB > 32 MB threshold.
+		const sof0 = new Uint8Array([
+			0xff,
+			0xd8, // SOI
+			0xff,
+			0xe0,
+			0x00,
+			0x10, // APP0 marker + length
+			0x4a,
+			0x46,
+			0x49,
+			0x46,
+			0x00, // "JFIF\0"
+			0x01,
+			0x01,
+			0x00,
+			0x00,
+			0x01,
+			0x00,
+			0x01,
+			0x00,
+			0x00, // JFIF fields
+			0xff,
+			0xc0,
+			0x00,
+			0x0b, // SOF0 marker + length
+			0x08, // precision
+			0x0f,
+			0xa0, // height = 4000
+			0x13,
+			0x88, // width = 5000
+			0x01, // number of components
+			0x01,
+			0x11,
+			0x00, // component
+		]);
+		const result = await generatePlaceholder(sof0, "image/jpeg");
+		expect(result).toBeNull();
+	});
+
+	it("returns null when fallback dimensions exceed memory budget", async () => {
+		// Unrecognizable buffer — image-size can't parse it, so fallback dims are used
+		const buffer = new Uint8Array([0x00, 0x01, 0x02, 0x03]);
+		const result = await generatePlaceholder(buffer, "image/jpeg", {
+			width: 5000,
+			height: 4000,
+		});
+		expect(result).toBeNull();
+	});
+
+	it("still generates placeholder for small images with dimensions param", async () => {
+		const result = await generatePlaceholder(new Uint8Array(JPEG_4x4), "image/jpeg", {
+			width: 4,
+			height: 4,
+		});
+		expect(result).not.toBeNull();
+		expect(result!.blurhash).toBeTruthy();
+	});
+});