const input = '{"outer":{"inner":"value"}}';

const result = formatToolOutputForSidebar(input);

expect(result).toContain("```json");

expect(result).toContain('"outer"');

expect(result).toContain('"inner"');

expect(result).toBe(`\`\`\`json

{

"outer": {

"inner": "value"

}

}

\`\`\``);

});

it("returns plain text for non-JSON content", () => {

const input = ' {"trimmed": true} ';

const result = formatToolOutputForSidebar(input);

expect(result).toContain("```json");

expect(result).toContain('"trimmed"');

expect(result).toBe(`\`\`\`json

{

"trimmed": true

}

\`\`\``);

});

it("handles whitespace-only string", () => {

const input = "a".repeat(150);

const result = getTruncatedPreview(input);

expect(result.length).toBe(101); // 100 chars + ellipsis

expect(result.endsWith("…")).toBe(true);

expect(result).toBe(`${"a".repeat(100)}…`);

});

it("truncates to max lines", () => {

const input = "Line 1\nLine 2\nLine 3";

const result = getTruncatedPreview(input);

expect(result.endsWith("…")).toBe(true);

expect(result).toBe("Line 1\nLine 2…");

});

it("does not add ellipsis when all lines fit", () => {

const input = "Line 1\nLine 2";

const result = getTruncatedPreview(input);

expect(result).toBe("Line 1\nLine 2");

expect(result.endsWith("…")).toBe(false);

});

it("handles single line within limits", () => {

const input = `${longLine}\n${longLine}`;

const result = getTruncatedPreview(input);

expect(result.length).toBe(101); // 100 + ellipsis

expect(result.endsWith("…")).toBe(true);

expect(result).toBe(`${"x".repeat(80)}\n${"x".repeat(19)}…`);

});

});

});