summaryrefslogtreecommitdiffstats
path: root/browser/components/sessionstore/test/browser_upgrade_backup.js
blob: fa0e34d42108ed524c996d976489e29709502047 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
/* Any copyright is dedicated to the Public Domain.
   http://creativecommons.org/publicdomain/zero/1.0/ */

const { Preferences } = ChromeUtils.importESModule(
  "resource://gre/modules/Preferences.sys.mjs"
);

const Paths = SessionFile.Paths;
const PREF_UPGRADE = "browser.sessionstore.upgradeBackup.latestBuildID";
const PREF_MAX_UPGRADE_BACKUPS =
  "browser.sessionstore.upgradeBackup.maxUpgradeBackups";

/**
 * Prepares tests by retrieving the current platform's build ID, clearing the
 * build where the last backup was created and creating arbitrary JSON data
 * for a new backup.
 */
function prepareTest() {
  let result = {};

  result.buildID = Services.appinfo.platformBuildID;
  Services.prefs.setCharPref(PREF_UPGRADE, "");
  result.contents = {
    "browser_upgrade_backup.js": Math.random(),
  };

  return result;
}

/**
 * Retrieves all upgrade backups and returns them in an array.
 */
async function getUpgradeBackups() {
  let children = await IOUtils.getChildren(Paths.backups);

  return children.filter(path => path.startsWith(Paths.upgradeBackupPrefix));
}

add_setup(async function () {
  // Wait until initialization is complete
  await SessionStore.promiseInitialized;
});

add_task(async function test_upgrade_backup() {
  let test = prepareTest();
  info("Let's check if we create an upgrade backup");
  await SessionFile.wipe();
  await IOUtils.writeJSON(Paths.clean, test.contents, {
    compress: true,
  });
  info("Call `SessionFile.read()` to set state to 'clean'");
  await SessionFile.read();
  await SessionFile.write(""); // First call to write() triggers the backup

  Assert.equal(
    Services.prefs.getCharPref(PREF_UPGRADE),
    test.buildID,
    "upgrade backup should be set"
  );

  Assert.ok(
    await IOUtils.exists(Paths.upgradeBackup),
    "upgrade backup file has been created"
  );

  let data = await IOUtils.readJSON(Paths.upgradeBackup, { decompress: true });
  Assert.deepEqual(
    test.contents,
    data,
    "upgrade backup contains the expected contents"
  );

  info("Let's check that we don't overwrite this upgrade backup");
  let newContents = {
    "something else entirely": Math.random(),
  };
  await IOUtils.writeJSON(Paths.clean, newContents, {
    compress: true,
  });
  await SessionFile.write(""); // Next call to write() shouldn't trigger the backup
  data = await IOUtils.readJSON(Paths.upgradeBackup, { decompress: true });
  Assert.deepEqual(test.contents, data, "upgrade backup hasn't changed");
});

add_task(async function test_upgrade_backup_removal() {
  let test = prepareTest();
  let maxUpgradeBackups = Preferences.get(PREF_MAX_UPGRADE_BACKUPS, 3);
  info("Let's see if we remove backups if there are too many");
  await SessionFile.wipe();
  await IOUtils.writeJSON(Paths.clean, test.contents, {
    compress: true,
  });
  info("Call `SessionFile.read()` to set state to 'clean'");
  await SessionFile.read();

  // create dummy backups
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20080101010101", "", {
    compress: true,
  });
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20090101010101", "", {
    compress: true,
  });
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20100101010101", "", {
    compress: true,
  });
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20110101010101", "", {
    compress: true,
  });
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20120101010101", "", {
    compress: true,
  });
  await IOUtils.writeUTF8(Paths.upgradeBackupPrefix + "20130101010101", "", {
    compress: true,
  });

  // get currently existing backups
  let backups = await getUpgradeBackups();

  info("Write the session to disk and perform a backup");
  await SessionFile.write(""); // First call to write() triggers the backup and the cleanup

  // a new backup should have been created (and still exist)
  is(
    Services.prefs.getCharPref(PREF_UPGRADE),
    test.buildID,
    "upgrade backup should be set"
  );
  Assert.ok(
    await IOUtils.exists(Paths.upgradeBackup),
    "upgrade backup file has been created"
  );

  // get currently existing backups and check their count
  let newBackups = await getUpgradeBackups();
  is(
    newBackups.length,
    maxUpgradeBackups,
    "expected number of backups are present after removing old backups"
  );

  // find all backups that were created during the last call to `SessionFile.write("");`
  // ie, filter out all the backups that have already been present before the call
  newBackups = newBackups.filter(function (backup) {
    return !backups.includes(backup);
  });

  // check that exactly one new backup was created
  is(newBackups.length, 1, "one new backup was created that was not removed");

  await SessionFile.write(""); // Second call to write() should not trigger anything

  backups = await getUpgradeBackups();
  is(
    backups.length,
    maxUpgradeBackups,
    "second call to SessionFile.write() didn't create or remove more backups"
  );
});