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// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.import { assertEquals, assertThrows } from "../assert/mod.ts";import { LogLevels } from "./levels.ts";import { FileHandler } from "./file_handler.ts";import { LogRecord } from "./logger.ts";
const LOG_FILE = "./file_handler_test_log.file";
Deno.test({  name: "FileHandler doesn't have broken line",  fn() {    class TestFileHandler extends FileHandler {      override flush() {        super.flush();        const decoder = new TextDecoder("utf-8");        const data = Deno.readFileSync(LOG_FILE);        const text = decoder.decode(data);        assertEquals(text.slice(-1), "\n");      }
      override destroy() {        super.destroy();        Deno.removeSync(LOG_FILE);      }    }
    using testFileHandler = new TestFileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });    testFileHandler.setup();
    for (let i = 0; i < 300; i++) {      testFileHandler.handle(        new LogRecord({          msg: "The starry heavens above me and the moral law within me.",          args: [],          level: LogLevels.WARN,          loggerName: "default",        }),      );    }  },});
Deno.test({  name: "FileHandler wipes existing log file clean with mode 'w'",  async fn() {    const fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });
    fileHandler.setup();    fileHandler.handle(      new LogRecord({        msg: "Hello World",        args: [],        level: LogLevels.WARN,        loggerName: "default",      }),    );    fileHandler.destroy();    const firstFileSize = (await Deno.stat(LOG_FILE)).size;
    fileHandler.setup();    fileHandler.handle(      new LogRecord({        msg: "Hello World",        args: [],        level: LogLevels.WARN,        loggerName: "default",      }),    );    fileHandler.destroy();    const secondFileSize = (await Deno.stat(LOG_FILE)).size;
    assertEquals(secondFileSize, firstFileSize);    Deno.removeSync(LOG_FILE);  },});
Deno.test({  name: "FileHandler throws if log file already exists with mode 'x'",  fn() {    using fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "x",    });    Deno.writeFileSync(LOG_FILE, new TextEncoder().encode("hello world"));
    assertThrows(() => {      fileHandler.setup();    }, Deno.errors.AlreadyExists);
    Deno.removeSync(LOG_FILE);  },});
Deno.test({  name: "FileHandler flushes buffer on unload",  async fn() {    const fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });    fileHandler.setup();    fileHandler.handle(      new LogRecord({        msg: "AAA",        args: [],        level: LogLevels.ERROR,        loggerName: "default",      }),    ); // 'ERROR AAA\n' = 10 bytes
    assertEquals((await Deno.stat(LOG_FILE)).size, 0);    dispatchEvent(new Event("unload"));    dispatchEvent(new Event("unload"));    assertEquals((await Deno.stat(LOG_FILE)).size, 10);
    Deno.removeSync(LOG_FILE);  },});
Deno.test({  name: "FileHandler triggers immediate flush on critical logs",  async fn() {    using fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });    fileHandler.setup();
    fileHandler.handle(      new LogRecord({        msg: "AAA",        args: [],        level: LogLevels.ERROR,        loggerName: "default",      }),    );
    // ERROR won't trigger immediate flush    const fileSize = (await Deno.stat(LOG_FILE)).size;    assertEquals(fileSize, 0);
    fileHandler.handle(      new LogRecord({        msg: "AAA",        args: [],        level: LogLevels.CRITICAL,        loggerName: "default",      }),    );
    // CRITICAL will trigger immediate flush    const fileSize2 = (await Deno.stat(LOG_FILE)).size;    // ERROR record is 10 bytes, CRITICAL is 13 bytes    assertEquals(fileSize2, 23);
    Deno.removeSync(LOG_FILE);  },});
Deno.test({  name: "FileHandler handles strings larger than the buffer",  fn() {    const fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });    const logOverBufferLimit = "A".repeat(4096);    fileHandler.setup();
    fileHandler.log(logOverBufferLimit);    fileHandler.destroy();
    assertEquals(      Deno.readTextFileSync(LOG_FILE),      `${logOverBufferLimit}\n`,    );
    Deno.removeSync(LOG_FILE);  },});
Deno.test({  name: "FileHandler handles a mixture of string sizes",  fn() {    const fileHandler = new FileHandler("WARN", {      filename: LOG_FILE,      mode: "w",    });    const veryLargeLog = "A".repeat(10000);    const regularLog = "B".repeat(100);    fileHandler.setup();
    fileHandler.log(regularLog);    fileHandler.log(veryLargeLog);    fileHandler.log(regularLog);    fileHandler.destroy();
    assertEquals(      Deno.readTextFileSync(LOG_FILE),      `${regularLog}\n${veryLargeLog}\n${regularLog}\n`,    );
    Deno.removeSync(LOG_FILE);  },});