fix(coding-agent): enforce safe auto-resized image limits closes #2055

packages/coding-agent/test/image-resize-callers.test.ts

@@ -0,0 +1,53 @@
+import { mkdirSync, rmSync, writeFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+
+vi.mock("../src/utils/image-resize.js", () => ({
+	resizeImage: vi.fn(),
+	formatDimensionNote: vi.fn(() => undefined),
+}));
+
+import { processFileArguments } from "../src/cli/file-processor.js";
+import { createReadTool } from "../src/core/tools/read.js";
+import { resizeImage } from "../src/utils/image-resize.js";
+
+const TINY_PNG_BASE64 =
+	"iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8DwHwAFBQIAX8jx0gAAAABJRU5ErkJggg==";
+
+describe("image resize callers", () => {
+	let testDir: string;
+
+	beforeEach(() => {
+		testDir = join(tmpdir(), `image-resize-callers-${Date.now()}`);
+		mkdirSync(testDir, { recursive: true });
+		vi.mocked(resizeImage).mockReset();
+		vi.mocked(resizeImage).mockResolvedValue(null);
+	});
+
+	afterEach(() => {
+		rmSync(testDir, { recursive: true, force: true });
+	});
+
+	it("read tool returns text-only output when auto-resize cannot produce a safe image", async () => {
+		const imagePath = join(testDir, "test.png");
+		writeFileSync(imagePath, Buffer.from(TINY_PNG_BASE64, "base64"));
+
+		const tool = createReadTool(testDir);
+		const result = await tool.execute("test-read-image", { path: imagePath });
+
+		expect(result.content).toHaveLength(1);
+		expect(result.content[0].type).toBe("text");
+		expect((result.content[0] as { type: "text"; text: string }).text).toContain("Image omitted");
+	});
+
+	it("file processor omits image attachments when auto-resize cannot produce a safe image", async () => {
+		const imagePath = join(testDir, "test.png");
+		writeFileSync(imagePath, Buffer.from(TINY_PNG_BASE64, "base64"));
+
+		const result = await processFileArguments([imagePath]);
+
+		expect(result.images).toHaveLength(0);
+		expect(result.text).toContain("Image omitted");
+	});
+});