feat(std/node) add appendFile and appendFileSync (#4294)

1 files changed, 166 insertions, 0 deletions

diff --git a/std/node/_fs/_fs_appendFile_test.ts b/std/node/_fs/_fs_appendFile_test.ts
new file mode 100644
index 000000000..dcea69783
--- /dev/null
+++ b/std/node/_fs/_fs_appendFile_test.ts
@@ -0,0 +1,166 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+const { test } = Deno;
+import {
+  assertEquals,
+  assert,
+  assertThrows,
+  assertThrowsAsync
+} from "../../testing/asserts.ts";
+import { appendFile, appendFileSync } from "./_fs_appendFile.ts";
+
+const decoder = new TextDecoder("utf-8");
+
+test({
+  name: "No callback Fn results in Error",
+  async fn() {
+    await assertThrowsAsync(
+      async () => {
+        await appendFile("some/path", "some data", "utf8");
+      },
+      Error,
+      "No callback function supplied"
+    );
+  }
+});
+
+test({
+  name: "Unsupported encoding results in error()",
+  async fn() {
+    await assertThrowsAsync(
+      async () => {
+        await appendFile(
+          "some/path",
+          "some data",
+          "made-up-encoding",
+          () => {}
+        );
+      },
+      Error,
+      "Only 'utf8' encoding is currently supported"
+    );
+    await assertThrowsAsync(
+      async () => {
+        await appendFile(
+          "some/path",
+          "some data",
+          { encoding: "made-up-encoding" },
+          () => {}
+        );
+      },
+      Error,
+      "Only 'utf8' encoding is currently supported"
+    );
+    assertThrows(
+      () => appendFileSync("some/path", "some data", "made-up-encoding"),
+      Error,
+      "Only 'utf8' encoding is currently supported"
+    );
+    assertThrows(
+      () =>
+        appendFileSync("some/path", "some data", {
+          encoding: "made-up-encoding"
+        }),
+      Error,
+      "Only 'utf8' encoding is currently supported"
+    );
+  }
+});
+
+test({
+  name: "Async: Data is written to passed in rid",
+  async fn() {
+    const tempFile: string = await Deno.makeTempFile();
+    const file: Deno.File = await Deno.open(tempFile, {
+      create: true,
+      write: true,
+      read: true
+    });
+    let calledBack = false;
+    await appendFile(file.rid, "hello world", () => {
+      calledBack = true;
+    });
+    assert(calledBack);
+    Deno.close(file.rid);
+    const data = await Deno.readFile(tempFile);
+    assertEquals(decoder.decode(data), "hello world");
+    await Deno.remove(tempFile);
+  }
+});
+
+test({
+  name: "Async: Data is written to passed in file path",
+  async fn() {
+    let calledBack = false;
+    const openResourcesBeforeAppend: Deno.ResourceMap = Deno.resources();
+    await appendFile("_fs_appendFile_test_file.txt", "hello world", () => {
+      calledBack = true;
+    });
+    assert(calledBack);
+    assertEquals(Deno.resources(), openResourcesBeforeAppend);
+    const data = await Deno.readFile("_fs_appendFile_test_file.txt");
+    assertEquals(decoder.decode(data), "hello world");
+    await Deno.remove("_fs_appendFile_test_file.txt");
+  }
+});
+
+test({
+  name:
+    "Async: Callback is made with error if attempting to append data to an existing file with 'ax' flag",
+  async fn() {
+    let calledBack = false;
+    const openResourcesBeforeAppend: Deno.ResourceMap = Deno.resources();
+    const tempFile: string = await Deno.makeTempFile();
+    await appendFile(tempFile, "hello world", { flag: "ax" }, (err: Error) => {
+      calledBack = true;
+      assert(err);
+    });
+    assert(calledBack);
+    assertEquals(Deno.resources(), openResourcesBeforeAppend);
+    await Deno.remove(tempFile);
+  }
+});
+
+test({
+  name: "Sync: Data is written to passed in rid",
+  fn() {
+    const tempFile: string = Deno.makeTempFileSync();
+    const file: Deno.File = Deno.openSync(tempFile, {
+      create: true,
+      write: true,
+      read: true
+    });
+    appendFileSync(file.rid, "hello world");
+    Deno.close(file.rid);
+    const data = Deno.readFileSync(tempFile);
+    assertEquals(decoder.decode(data), "hello world");
+    Deno.removeSync(tempFile);
+  }
+});
+
+test({
+  name: "Sync: Data is written to passed in file path",
+  fn() {
+    const openResourcesBeforeAppend: Deno.ResourceMap = Deno.resources();
+    appendFileSync("_fs_appendFile_test_file_sync.txt", "hello world");
+    assertEquals(Deno.resources(), openResourcesBeforeAppend);
+    const data = Deno.readFileSync("_fs_appendFile_test_file_sync.txt");
+    assertEquals(decoder.decode(data), "hello world");
+    Deno.removeSync("_fs_appendFile_test_file_sync.txt");
+  }
+});
+
+test({
+  name:
+    "Sync: error thrown if attempting to append data to an existing file with 'ax' flag",
+  fn() {
+    const openResourcesBeforeAppend: Deno.ResourceMap = Deno.resources();
+    const tempFile: string = Deno.makeTempFileSync();
+    assertThrows(
+      () => appendFileSync(tempFile, "hello world", { flag: "ax" }),
+      Deno.errors.AlreadyExists,
+      ""
+    );
+    assertEquals(Deno.resources(), openResourcesBeforeAppend);
+    Deno.removeSync(tempFile);
+  }
+});