chore(vendor): import pi 1.3.0

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: 71023aec1546d6d677a65669c5665c0927ce0dd0

third_party/pi/packages/durable/test/env-truncate.test.ts

@@ -0,0 +1,100 @@
+import { execFileSync } from "node:child_process";
+import { fileURLToPath } from "node:url";
+import { describe, expect, it } from "vitest";
+import { formatSize, truncateHead } from "../src/truncate.ts";
+
+const encoder = new TextEncoder();
+
+function byteLength(content: string): number {
+	return encoder.encode(content).length;
+}
+
+describe("truncate utilities", () => {
+	it("reports UTF-8 byte counts in truncation results", () => {
+		const content = "aé🙂\nb";
+		const result = truncateHead(content, { maxBytes: 100, maxLines: 10 });
+
+		expect(result.truncated).toBe(false);
+		expect(result.totalBytes).toBe(byteLength(content));
+		expect(result.outputBytes).toBe(byteLength(content));
+		expect(result.totalBytes).toBe(9);
+	});
+
+	it("counts UTF-8 bytes and truncates correctly in a runtime without Buffer", () => {
+		const inputs = ["", "ascii", "é", "中", "🙂", "\ud83d", "\ude42", "a\ud83d\ude42b", "\u07ff\u0800\uffff"];
+		const output = execFileSync(
+			process.execPath,
+			[
+				// Workspace packages from source, as the test runner resolves them, not from a possibly stale build.
+				"--conditions=source",
+				"--import",
+				new URL("./fixtures/delete-buffer.ts", import.meta.url).href,
+				fileURLToPath(new URL("./fixtures/utf8-byte-length-without-buffer.ts", import.meta.url)),
+				JSON.stringify(inputs),
+			],
+			{ encoding: "utf8" },
+		);
+		const result = JSON.parse(output) as {
+			bufferAvailable: boolean;
+			lengths: number[];
+			head: { content: string; outputBytes: number; truncatedBy: string | null };
+		};
+		expect(result.bufferAvailable).toBe(false);
+		expect(result.lengths).toEqual(inputs.map(byteLength));
+		expect(result.head).toMatchObject({ content: "aé🙂", outputBytes: 7, truncatedBy: "bytes" });
+	});
+
+	it("does not count a trailing newline as an extra line", () => {
+		const content = `${Array.from({ length: 3 }, () => "line").join("\n")}\n`;
+		const head = truncateHead(content, { maxBytes: 100, maxLines: 3 });
+
+		expect(head).toMatchObject({ truncated: false, totalLines: 3, outputLines: 3 });
+	});
+
+	it("truncates head by line limits", () => {
+		const content = "one\ntwo\nthree\nfour";
+		expect(truncateHead(content, { maxBytes: 100, maxLines: 2 })).toMatchObject({
+			content: "one\ntwo",
+			truncated: true,
+			truncatedBy: "lines",
+			totalLines: 4,
+			outputLines: 2,
+		});
+	});
+
+	it("reports bytes when only a trailing newline exceeds limits at the line cap", () => {
+		expect(truncateHead("hello\nworld\n", { maxBytes: 11, maxLines: 2 })).toMatchObject({
+			content: "hello\nworld",
+			truncated: true,
+			truncatedBy: "bytes",
+			totalLines: 2,
+			outputLines: 2,
+		});
+	});
+
+	it("truncates head on UTF-8 byte limits without partial lines", () => {
+		const content = "éé\nabc";
+		const result = truncateHead(content, { maxBytes: 4, maxLines: 10 });
+
+		expect(result.content).toBe("éé");
+		expect(result.truncated).toBe(true);
+		expect(result.truncatedBy).toBe("bytes");
+		expect(result.outputBytes).toBe(4);
+		expect(result.firstLineExceedsLimit).toBe(false);
+	});
+
+	it("reports head truncation when the first line exceeds the byte limit", () => {
+		const result = truncateHead("éé\nabc", { maxBytes: 3, maxLines: 10 });
+
+		expect(result.content).toBe("");
+		expect(result.truncated).toBe(true);
+		expect(result.truncatedBy).toBe("bytes");
+		expect(result.firstLineExceedsLimit).toBe(true);
+	});
+
+	it("formats sizes", () => {
+		expect(formatSize(1023)).toBe("1023B");
+		expect(formatSize(1536)).toBe("1.5KB");
+		expect(formatSize(3 * 1024 * 1024)).toBe("3.0MB");
+	});
+});