test: add tests for readFile flags

nodejs · O4epegb · Sep 22, 2020 · Sep 23, 2020 · Sep 24, 2020 · Oct 12, 2020
commit e5834a75e1078b51edd91765c2da1ca7c9c474a8
diff --git a/test/parallel/test-fs-readfile-flags.js b/test/parallel/test-fs-readfile-flags.js
@@ -0,0 +1,70 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+'use strict';
+
+// Test of fs.readFile with different flags.
+const common = require('../common');
+const fs = require('fs');
+const assert = require('assert');
+const fixtures = require('../common/fixtures');
+
+const fn = fixtures.path('empty.txt');
+const nonexistingFn = fixtures.path('nonexistingfile.txt');
+const nonexistingFn2 = fixtures.path('nonexistingfile2.txt');
+
+fs.readFile(
+  fn,
+  // With `a+` the file is created if it does not exist
+  { encoding: 'utf8', flag: 'a+' },
+  common.mustCall((err, data) => {
+    assert.strictEqual(data, '');
+  })
+);
+
+fs.readFile(
+  fn,
+  // Like `a+` but fails if the path exists.
+  { encoding: 'utf8', flag: 'ax+' },
+  common.mustCall((err, data) => {
+    assert.strictEqual(err.code, 'EEXIST');
+  })
+);
+
+fs.readFile(
+  nonexistingFn,
+  // With `a+` the file is created if it does not exist
+  { encoding: 'utf8', flag: 'a+' },
+  common.mustCall((err, data) => {
+    assert.strictEqual(data, '');
+
+    fs.unlinkSync(nonexistingFn);
+  })
+);
+
+fs.readFile(
+  nonexistingFn2,
+  // Default flag is `r`. An exception occurs if the file does not exist.
+  { encoding: 'utf8' },
+  common.mustCall((err, data) => {
+    assert.strictEqual(err.code, 'ENOENT');
+  })
+);