Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 1327 insertions, 0 deletions

diff --git a/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/LICENSE b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/LICENSE
new file mode 100644
index 0000000000..e87a115e46
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/LICENSE
@@ -0,0 +1,363 @@
+Mozilla Public License, version 2.0
+
+1. Definitions
+
+1.1. "Contributor"
+
+     means each individual or legal entity that creates, contributes to the
+     creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+
+     means the combination of the Contributions of others (if any) used by a
+     Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+
+     means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+
+     means Source Code Form to which the initial Contributor has attached the
+     notice in Exhibit A, the Executable Form of such Source Code Form, and
+     Modifications of such Source Code Form, in each case including portions
+     thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+     means
+
+     a. that the initial Contributor has attached the notice described in
+        Exhibit B to the Covered Software; or
+
+     b. that the Covered Software was made available under the terms of
+        version 1.1 or earlier of the License, but not also under the terms of
+        a Secondary License.
+
+1.6. "Executable Form"
+
+     means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+
+     means a work that combines Covered Software with other material, in a
+     separate file or files, that is not Covered Software.
+
+1.8. "License"
+
+     means this document.
+
+1.9. "Licensable"
+
+     means having the right to grant, to the maximum extent possible, whether
+     at the time of the initial grant or subsequently, any and all of the
+     rights conveyed by this License.
+
+1.10. "Modifications"
+
+     means any of the following:
+
+     a. any file in Source Code Form that results from an addition to,
+        deletion from, or modification of the contents of Covered Software; or
+
+     b. any new file in Source Code Form that contains any Covered Software.
+
+1.11. "Patent Claims" of a Contributor
+
+      means any patent claim(s), including without limitation, method,
+      process, and apparatus claims, in any patent Licensable by such
+      Contributor that would be infringed, but for the grant of the License,
+      by the making, using, selling, offering for sale, having made, import,
+      or transfer of either its Contributions or its Contributor Version.
+
+1.12. "Secondary License"
+
+      means either the GNU General Public License, Version 2.0, the GNU Lesser
+      General Public License, Version 2.1, the GNU Affero General Public
+      License, Version 3.0, or any later versions of those licenses.
+
+1.13. "Source Code Form"
+
+      means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+
+      means an individual or a legal entity exercising rights under this
+      License. For legal entities, "You" includes any entity that controls, is
+      controlled by, or is under common control with You. For purposes of this
+      definition, "control" means (a) the power, direct or indirect, to cause
+      the direction or management of such entity, whether by contract or
+      otherwise, or (b) ownership of more than fifty percent (50%) of the
+      outstanding shares or beneficial ownership of such entity.
+
+
+2. License Grants and Conditions
+
+2.1. Grants
+
+     Each Contributor hereby grants You a world-wide, royalty-free,
+     non-exclusive license:
+
+     a. under intellectual property rights (other than patent or trademark)
+        Licensable by such Contributor to use, reproduce, make available,
+        modify, display, perform, distribute, and otherwise exploit its
+        Contributions, either on an unmodified basis, with Modifications, or
+        as part of a Larger Work; and
+
+     b. under Patent Claims of such Contributor to make, use, sell, offer for
+        sale, have made, import, and otherwise transfer either its
+        Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+     The licenses granted in Section 2.1 with respect to any Contribution
+     become effective for each Contribution on the date the Contributor first
+     distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+     The licenses granted in this Section 2 are the only rights granted under
+     this License. No additional rights or licenses will be implied from the
+     distribution or licensing of Covered Software under this License.
+     Notwithstanding Section 2.1(b) above, no patent license is granted by a
+     Contributor:
+
+     a. for any code that a Contributor has removed from Covered Software; or
+
+     b. for infringements caused by: (i) Your and any other third party's
+        modifications of Covered Software, or (ii) the combination of its
+        Contributions with other software (except as part of its Contributor
+        Version); or
+
+     c. under Patent Claims infringed by Covered Software in the absence of
+        its Contributions.
+
+     This License does not grant any rights in the trademarks, service marks,
+     or logos of any Contributor (except as may be necessary to comply with
+     the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+     No Contributor makes additional grants as a result of Your choice to
+     distribute the Covered Software under a subsequent version of this
+     License (see Section 10.2) or under the terms of a Secondary License (if
+     permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+     Each Contributor represents that the Contributor believes its
+     Contributions are its original creation(s) or it has sufficient rights to
+     grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+     This License is not intended to limit any rights You have under
+     applicable copyright doctrines of fair use, fair dealing, or other
+     equivalents.
+
+2.7. Conditions
+
+     Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted in
+     Section 2.1.
+
+
+3. Responsibilities
+
+3.1. Distribution of Source Form
+
+     All distribution of Covered Software in Source Code Form, including any
+     Modifications that You create or to which You contribute, must be under
+     the terms of this License. You must inform recipients that the Source
+     Code Form of the Covered Software is governed by the terms of this
+     License, and how they can obtain a copy of this License. You may not
+     attempt to alter or restrict the recipients' rights in the Source Code
+     Form.
+
+3.2. Distribution of Executable Form
+
+     If You distribute Covered Software in Executable Form then:
+
+     a. such Covered Software must also be made available in Source Code Form,
+        as described in Section 3.1, and You must inform recipients of the
+        Executable Form how they can obtain a copy of such Source Code Form by
+        reasonable means in a timely manner, at a charge no more than the cost
+        of distribution to the recipient; and
+
+     b. You may distribute such Executable Form under the terms of this
+        License, or sublicense it under different terms, provided that the
+        license for the Executable Form does not attempt to limit or alter the
+        recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+     You may create and distribute a Larger Work under terms of Your choice,
+     provided that You also comply with the requirements of this License for
+     the Covered Software. If the Larger Work is a combination of Covered
+     Software with a work governed by one or more Secondary Licenses, and the
+     Covered Software is not Incompatible With Secondary Licenses, this
+     License permits You to additionally distribute such Covered Software
+     under the terms of such Secondary License(s), so that the recipient of
+     the Larger Work may, at their option, further distribute the Covered
+     Software under the terms of either this License or such Secondary
+     License(s).
+
+3.4. Notices
+
+     You may not remove or alter the substance of any license notices
+     (including copyright notices, patent notices, disclaimers of warranty, or
+     limitations of liability) contained within the Source Code Form of the
+     Covered Software, except that You may alter any license notices to the
+     extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+     You may choose to offer, and to charge a fee for, warranty, support,
+     indemnity or liability obligations to one or more recipients of Covered
+     Software. However, You may do so only on Your own behalf, and not on
+     behalf of any Contributor. You must make it absolutely clear that any
+     such warranty, support, indemnity, or liability obligation is offered by
+     You alone, and You hereby agree to indemnify every Contributor for any
+     liability incurred by such Contributor as a result of warranty, support,
+     indemnity or liability terms You offer. You may include additional
+     disclaimers of warranty and limitations of liability specific to any
+     jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+
+   If it is impossible for You to comply with any of the terms of this License
+   with respect to some or all of the Covered Software due to statute,
+   judicial order, or regulation then You must: (a) comply with the terms of
+   this License to the maximum extent possible; and (b) describe the
+   limitations and the code they affect. Such description must be placed in a
+   text file included with all distributions of the Covered Software under
+   this License. Except to the extent prohibited by statute or regulation,
+   such description must be sufficiently detailed for a recipient of ordinary
+   skill to be able to understand it.
+
+5. Termination
+
+5.1. The rights granted under this License will terminate automatically if You
+     fail to comply with any of its terms. However, if You become compliant,
+     then the rights granted under this License from a particular Contributor
+     are reinstated (a) provisionally, unless and until such Contributor
+     explicitly and finally terminates Your grants, and (b) on an ongoing
+     basis, if such Contributor fails to notify You of the non-compliance by
+     some reasonable means prior to 60 days after You have come back into
+     compliance. Moreover, Your grants from a particular Contributor are
+     reinstated on an ongoing basis if such Contributor notifies You of the
+     non-compliance by some reasonable means, this is the first time You have
+     received notice of non-compliance with this License from such
+     Contributor, and You become compliant prior to 30 days after Your receipt
+     of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+     infringement claim (excluding declaratory judgment actions,
+     counter-claims, and cross-claims) alleging that a Contributor Version
+     directly or indirectly infringes any patent, then the rights granted to
+     You by any and all Contributors for the Covered Software under Section
+     2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all end user
+     license agreements (excluding distributors and resellers) which have been
+     validly granted by You or Your distributors under this License prior to
+     termination shall survive termination.
+
+6. Disclaimer of Warranty
+
+   Covered Software is provided under this License on an "as is" basis,
+   without warranty of any kind, either expressed, implied, or statutory,
+   including, without limitation, warranties that the Covered Software is free
+   of defects, merchantable, fit for a particular purpose or non-infringing.
+   The entire risk as to the quality and performance of the Covered Software
+   is with You. Should any Covered Software prove defective in any respect,
+   You (not any Contributor) assume the cost of any necessary servicing,
+   repair, or correction. This disclaimer of warranty constitutes an essential
+   part of this License. No use of  any Covered Software is authorized under
+   this License except under this disclaimer.
+
+7. Limitation of Liability
+
+   Under no circumstances and under no legal theory, whether tort (including
+   negligence), contract, or otherwise, shall any Contributor, or anyone who
+   distributes Covered Software as permitted above, be liable to You for any
+   direct, indirect, special, incidental, or consequential damages of any
+   character including, without limitation, damages for lost profits, loss of
+   goodwill, work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses, even if such party shall have been
+   informed of the possibility of such damages. This limitation of liability
+   shall not apply to liability for death or personal injury resulting from
+   such party's negligence to the extent applicable law prohibits such
+   limitation. Some jurisdictions do not allow the exclusion or limitation of
+   incidental or consequential damages, so this exclusion and limitation may
+   not apply to You.
+
+8. Litigation
+
+   Any litigation relating to this License may be brought only in the courts
+   of a jurisdiction where the defendant maintains its principal place of
+   business and such litigation shall be governed by laws of that
+   jurisdiction, without reference to its conflict-of-law provisions. Nothing
+   in this Section shall prevent a party's ability to bring cross-claims or
+   counter-claims.
+
+9. Miscellaneous
+
+   This License represents the complete agreement concerning the subject
+   matter hereof. If any provision of this License is held to be
+   unenforceable, such provision shall be reformed only to the extent
+   necessary to make it enforceable. Any law or regulation which provides that
+   the language of a contract shall be construed against the drafter shall not
+   be used to construe this License against a Contributor.
+
+
+10. Versions of the License
+
+10.1. New Versions
+
+      Mozilla Foundation is the license steward. Except as provided in Section
+      10.3, no one other than the license steward has the right to modify or
+      publish new versions of this License. Each version will be given a
+      distinguishing version number.
+
+10.2. Effect of New Versions
+
+      You may distribute the Covered Software under the terms of the version
+      of the License under which You originally received the Covered Software,
+      or under the terms of any subsequent version published by the license
+      steward.
+
+10.3. Modified Versions
+
+      If you create software not governed by this License, and you want to
+      create a new license for such software, you may create and use a
+      modified version of this License if you rename the license and remove
+      any references to the name of the license steward (except to note that
+      such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+      Licenses If You choose to distribute Source Code Form that is
+      Incompatible With Secondary Licenses under the terms of this version of
+      the License, the notice described in Exhibit B of this License must be
+      attached.
+
+Exhibit A - Source Code Form License Notice
+
+      This Source Code Form is subject to the
+      terms of the Mozilla Public License, v.
+      2.0. If a copy of the MPL was not
+      distributed with this file, You can
+      obtain one at
+      http://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular file,
+then You may include the notice in a location (such as a LICENSE file in a
+relevant directory) where a recipient would be likely to look for such a
+notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+
+      This Source Code Form is "Incompatible
+      With Secondary Licenses", as defined by
+      the Mozilla Public License, v. 2.0.
+
diff --git a/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/METADATA b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/METADATA
new file mode 100644
index 0000000000..cd20533c13
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/METADATA
@@ -0,0 +1,17 @@
+Metadata-Version: 2.1
+Name: mozilla-version
+Version: 0.3.4
+Summary: Process Firefox versions numbers. Tells whether they are valid or not, whether they are nightlies or regular releases, whether this version precedes that other.    
+Home-page: https://github.com/mozilla-releng/mozilla-version
+Author: Mozilla Release Engineering
+Author-email: release+python@mozilla.com
+License: MPL2
+Platform: UNKNOWN
+Classifier: Programming Language :: Python :: 2.7
+Classifier: Programming Language :: Python :: 3
+Requires-Dist: attrs
+Requires-Dist: enum34 ; python_version < "3.4"
+
+UNKNOWN
+
+
diff --git a/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/RECORD b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/RECORD
new file mode 100644
index 0000000000..71d5e5b4ce
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/RECORD
@@ -0,0 +1,17 @@
+mozilla_version/__init__.py,sha256=ro9IDUmjUco6GHJhqbgynResbswRnh6HL5Iv1ttDuWU,60
+mozilla_version/balrog.py,sha256=TjRzV-3E1NVEqqXVda5dhzUMdXuiZ2CYqH-Uf-JgnBA,4975
+mozilla_version/errors.py,sha256=bahCd1gb9rW3e23ZjdVOJvF7IQ9kSOKycO4juE2cHQA,2176
+mozilla_version/gecko.py,sha256=C2beofD_Sfs2YNyq9PRe28oGvAX61aOCGLCnWNIMHJg,15337
+mozilla_version/maven.py,sha256=9UXfvpGLOtO1U1mCScuyu2-0U-VdHPtLemOcN-PByyE,1720
+mozilla_version/parser.py,sha256=bLDrJ7JQzHLkAKoKMWX6nQvKIBZV9vqroqDZUfNUMts,1359
+mozilla_version/version.py,sha256=vJVaPjRgKQtNXhA-gWiHTJjzPJwR6uhszeTZ1yay64c,5411
+mozilla_version/test/__init__.py,sha256=r9z_NrSZeN6vCBiocNFI00XPm2bveSogzO-jsLa7Q-I,87
+mozilla_version/test/test_balrog.py,sha256=IqZjc4K5S0vtE3VtYKezbBU6ZHxxkrEdPFgH2so21UU,7839
+mozilla_version/test/test_gecko.py,sha256=pRZ5YT_n0blv2zSvTYkPictZbsnhbEGXlmWzLrC3kfQ,14622
+mozilla_version/test/test_maven.py,sha256=jNe-drnPwc_DkqZPnTasdK_QGNmqqxLAprX6VRFyMzs,2892
+mozilla_version/test/test_version.py,sha256=RGkyZhkRF8FW_MUN6HZNSKOmFHRLR8gPKJG_N-GGqI4,5465
+mozilla_version-0.3.4.dist-info/LICENSE,sha256=YCIsKMGn9qksffmOXF9EWeYk5uKF4Lm5RGevX2qzND0,15922
+mozilla_version-0.3.4.dist-info/METADATA,sha256=oUEXSEKibWqJsbh8uWqaUqHOkruAShgZGQH09etZVVE,580
+mozilla_version-0.3.4.dist-info/WHEEL,sha256=h_aVn5OB2IERUjMbi2pucmR_zzWJtk303YXvhh60NJ8,110
+mozilla_version-0.3.4.dist-info/top_level.txt,sha256=K1r8SXa4ny0i7OTfimG0Ct33oHkXtLjuU1E5_aHBe94,16
+mozilla_version-0.3.4.dist-info/RECORD,,
diff --git a/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/WHEEL b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/WHEEL
new file mode 100644
index 0000000000..78e6f69d1d
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/WHEEL
@@ -0,0 +1,6 @@
+Wheel-Version: 1.0
+Generator: bdist_wheel (0.33.4)
+Root-Is-Purelib: true
+Tag: py2-none-any
+Tag: py3-none-any
+
diff --git a/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/top_level.txt b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/top_level.txt
new file mode 100644
index 0000000000..f5c7efa40b
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version-0.3.4.dist-info/top_level.txt
@@ -0,0 +1 @@
+mozilla_version
diff --git a/third_party/python/mozilla_version/mozilla_version/__init__.py b/third_party/python/mozilla_version/mozilla_version/__init__.py
new file mode 100644
index 0000000000..ba46ee264d
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/__init__.py
@@ -0,0 +1 @@
+"""Defines characteristics of Mozilla's version numbers."""
diff --git a/third_party/python/mozilla_version/mozilla_version/balrog.py b/third_party/python/mozilla_version/mozilla_version/balrog.py
new file mode 100644
index 0000000000..0860d5698a
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/balrog.py
@@ -0,0 +1,142 @@
+"""Defines characteristics of a Balrog release name.
+
+Balrog is the server that delivers Firefox and Thunderbird updates. Release names follow
+the pattern "{product}-{version}-build{build_number}"
+
+Examples:
+    .. code-block:: python
+
+        from mozilla_version.balrog import BalrogReleaseName
+
+        balrog_release = BalrogReleaseName.parse('firefox-60.0.1-build1')
+
+        balrog_release.product                 # firefox
+        balrog_release.version.major_number    # 60
+        str(balrog_release)                    # 'firefox-60.0.1-build1'
+
+        previous_release = BalrogReleaseName.parse('firefox-60.0-build2')
+        previous_release < balrog_release      # True
+
+        invalid = BalrogReleaseName.parse('60.0.1')           # raises PatternNotMatchedError
+        invalid = BalrogReleaseName.parse('firefox-60.0.1')   # raises PatternNotMatchedError
+
+        # Releases can be built thanks to version classes like FirefoxVersion
+        BalrogReleaseName('firefox', FirefoxVersion(60, 0, 1, 1))  # 'firefox-60.0.1-build1'
+
+"""
+
+import attr
+import re
+
+from mozilla_version.errors import PatternNotMatchedError
+from mozilla_version.parser import get_value_matched_by_regex
+from mozilla_version.gecko import (
+    GeckoVersion, FirefoxVersion, DeveditionVersion, FennecVersion, ThunderbirdVersion
+)
+
+
+_VALID_ENOUGH_BALROG_RELEASE_PATTERN = re.compile(
+    r"^(?P<product>[a-z]+)-(?P<version>.+)$", re.IGNORECASE
+)
+
+
+_SUPPORTED_PRODUCTS = {
+    'firefox': FirefoxVersion,
+    'devedition': DeveditionVersion,
+    'fennec': FennecVersion,
+    'thunderbird': ThunderbirdVersion,
+}
+
+
+def _supported_product(string):
+    product = string.lower()
+    if product not in _SUPPORTED_PRODUCTS:
+        raise PatternNotMatchedError(string, pattern='unknown product')
+    return product
+
+
+def _products_must_be_identical(method):
+    def checker(this, other):
+        if this.product != other.product:
+            raise ValueError('Cannot compare "{}" and "{}"'.format(this.product, other.product))
+        return method(this, other)
+    return checker
+
+
+@attr.s(frozen=True, cmp=False, hash=True)
+class BalrogReleaseName(object):
+    """Class that validates and handles Balrog release names.
+
+    Raises:
+        PatternNotMatchedError: if a parsed string doesn't match the pattern of a valid release
+        MissingFieldError: if a mandatory field is missing in the string. Mandatory fields are
+            `product`, `major_number`, `minor_number`, and `build_number`
+        ValueError: if an integer can't be cast or is not (strictly) positive
+        TooManyTypesError: if the string matches more than 1 `VersionType`
+        NoVersionTypeError: if the string matches none.
+
+    """
+
+    product = attr.ib(type=str, converter=_supported_product)
+    version = attr.ib(type=GeckoVersion)
+
+    def __attrs_post_init__(self):
+        """Ensure attributes are sane all together."""
+        if self.version.build_number is None:
+            raise PatternNotMatchedError(self, pattern='build_number must exist')
+
+    @classmethod
+    def parse(cls, release_string):
+        """Construct an object representing a valid Firefox version number."""
+        regex_matches = _VALID_ENOUGH_BALROG_RELEASE_PATTERN.match(release_string)
+        if regex_matches is None:
+            raise PatternNotMatchedError(release_string, _VALID_ENOUGH_BALROG_RELEASE_PATTERN)
+
+        product = get_value_matched_by_regex('product', regex_matches, release_string)
+        try:
+            VersionClass = _SUPPORTED_PRODUCTS[product.lower()]
+        except KeyError:
+            raise PatternNotMatchedError(release_string, pattern='unknown product')
+
+        version_string = get_value_matched_by_regex('version', regex_matches, release_string)
+        version = VersionClass.parse(version_string)
+
+        return cls(product, version)
+
+    def __str__(self):
+        """Implement string representation.
+
+        Computes a new string based on the given attributes.
+        """
+        version_string = str(self.version).replace('build', '-build')
+        return '{}-{}'.format(self.product, version_string)
+
+    @_products_must_be_identical
+    def __eq__(self, other):
+        """Implement `==` operator."""
+        return self.version == other.version
+
+    @_products_must_be_identical
+    def __ne__(self, other):
+        """Implement `!=` operator."""
+        return self.version != other.version
+
+    @_products_must_be_identical
+    def __lt__(self, other):
+        """Implement `<` operator."""
+        return self.version < other.version
+
+    @_products_must_be_identical
+    def __le__(self, other):
+        """Implement `<=` operator."""
+        return self.version <= other.version
+
+    @_products_must_be_identical
+    def __gt__(self, other):
+        """Implement `>` operator."""
+        return self.version > other.version
+
+    @_products_must_be_identical
+    def __ge__(self, other):
+        """Implement `>=` operator."""
+        return self.version >= other.version
diff --git a/third_party/python/mozilla_version/mozilla_version/errors.py b/third_party/python/mozilla_version/mozilla_version/errors.py
new file mode 100644
index 0000000000..84cd2169f5
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/errors.py
@@ -0,0 +1,64 @@
+"""Defines all errors reported by mozilla-version."""
+
+
+class PatternNotMatchedError(ValueError):
+    """Error when a string doesn't match an expected pattern.
+
+    Args:
+        string (str): The string it was unable to match.
+        pattern (str): The pattern used it tried to match.
+    """
+
+    def __init__(self, string, pattern):
+        """Constructor."""
+        super(PatternNotMatchedError, self).__init__(
+            '"{}" does not match the pattern: {}'.format(string, pattern)
+        )
+
+
+class NoVersionTypeError(ValueError):
+    """Error when `version_string` matched the pattern, but was unable to find its type.
+
+    Args:
+        version_string (str): The string it was unable to guess the type.
+    """
+
+    def __init__(self, version_string):
+        """Constructor."""
+        super(NoVersionTypeError, self).__init__(
+            'Version "{}" matched the pattern of a valid version, but it is unable to find what type it is. \
+This is likely a bug in mozilla-version'.format(version_string)
+        )
+
+
+class MissingFieldError(ValueError):
+    """Error when `version_string` lacks an expected field.
+
+    Args:
+        version_string (str): The string it was unable to extract a given field.
+        field_name (str): The name of the missing field.
+    """
+
+    def __init__(self, version_string, field_name):
+        """Constructor."""
+        super(MissingFieldError, self).__init__(
+            'Release "{}" does not contain a valid {}'.format(version_string, field_name)
+        )
+
+
+class TooManyTypesError(ValueError):
+    """Error when `version_string` has too many types."""
+
+    def __init__(self, version_string, first_matched_type, second_matched_type):
+        """Constructor.
+
+        Args:
+            version_string (str): The string that gave too many types.
+            first_matched_type (str): The name of the first detected type.
+            second_matched_type (str): The name of the second detected type
+        """
+        super(TooManyTypesError, self).__init__(
+            'Release "{}" cannot match types "{}" and "{}"'.format(
+                version_string, first_matched_type, second_matched_type
+            )
+        )
diff --git a/third_party/python/mozilla_version/mozilla_version/gecko.py b/third_party/python/mozilla_version/mozilla_version/gecko.py
new file mode 100644
index 0000000000..dd14dda6b0
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/gecko.py
@@ -0,0 +1,435 @@
+"""Defines characteristics of a Gecko version number, including Firefox.
+
+Examples:
+    .. code-block:: python
+
+        from mozilla_version.gecko import FirefoxVersion
+
+        version = FirefoxVersion.parse('60.0.1')
+
+        version.major_number    # 60
+        version.minor_number    # 0
+        version.patch_number    # 1
+
+        version.is_release  # True
+        version.is_beta     # False
+        version.is_nightly  # False
+
+        str(version)        # '60.0.1'
+
+        previous_version = FirefoxVersion.parse('60.0b14')
+        previous_version < version      # True
+
+        previous_version.beta_number    # 14
+        previous_version.major_number   # 60
+        previous_version.minor_number   # 0
+        previous_version.patch_number   # raises AttributeError
+
+        previous_version.is_beta     # True
+        previous_version.is_release  # False
+        previous_version.is_nightly  # False
+
+        invalid_version = FirefoxVersion.parse('60.1')      # raises PatternNotMatchedError
+        invalid_version = FirefoxVersion.parse('60.0.0')    # raises PatternNotMatchedError
+        version = FirefoxVersion.parse('60.0')    # valid
+
+        # Versions can be built by raw values
+        FirefoxVersion(60, 0))         # '60.0'
+        FirefoxVersion(60, 0, 1))      # '60.0.1'
+        FirefoxVersion(60, 1, 0))      # '60.1.0'
+        FirefoxVersion(60, 0, 1, 1))   # '60.0.1build1'
+        FirefoxVersion(60, 0, beta_number=1))       # '60.0b1'
+        FirefoxVersion(60, 0, is_nightly=True))     # '60.0a1'
+        FirefoxVersion(60, 0, is_aurora_or_devedition=True))    # '60.0a2'
+        FirefoxVersion(60, 0, is_esr=True))         # '60.0esr'
+        FirefoxVersion(60, 0, 1, is_esr=True))      # '60.0.1esr'
+
+"""
+
+import attr
+import re
+
+from mozilla_version.errors import (
+    PatternNotMatchedError, TooManyTypesError, NoVersionTypeError
+)
+from mozilla_version.parser import strictly_positive_int_or_none
+from mozilla_version.version import BaseVersion, VersionType
+
+
+def _find_type(version):
+    version_type = None
+
+    def ensure_version_type_is_not_already_defined(previous_type, candidate_type):
+        if previous_type is not None:
+            raise TooManyTypesError(
+                str(version), previous_type, candidate_type
+            )
+
+    if version.is_nightly:
+        version_type = VersionType.NIGHTLY
+    if version.is_aurora_or_devedition:
+        ensure_version_type_is_not_already_defined(
+            version_type, VersionType.AURORA_OR_DEVEDITION
+        )
+        version_type = VersionType.AURORA_OR_DEVEDITION
+    if version.is_beta:
+        ensure_version_type_is_not_already_defined(version_type, VersionType.BETA)
+        version_type = VersionType.BETA
+    if version.is_esr:
+        ensure_version_type_is_not_already_defined(version_type, VersionType.ESR)
+        version_type = VersionType.ESR
+    if version.is_release:
+        ensure_version_type_is_not_already_defined(version_type, VersionType.RELEASE)
+        version_type = VersionType.RELEASE
+
+    if version_type is None:
+        raise NoVersionTypeError(str(version))
+
+    return version_type
+
+
+@attr.s(frozen=True, cmp=False, hash=True)
+class GeckoVersion(BaseVersion):
+    """Class that validates and handles version numbers for Gecko-based products.
+
+    You may want to use specific classes like FirefoxVersion. These classes define edge cases
+    that were shipped.
+
+    Raises:
+        PatternNotMatchedError: if the string doesn't match the pattern of a valid version number
+        MissingFieldError: if a mandatory field is missing in the string. Mandatory fields are
+            `major_number` and `minor_number`
+        ValueError: if an integer can't be cast or is not (strictly) positive
+        TooManyTypesError: if the string matches more than 1 `VersionType`
+        NoVersionTypeError: if the string matches none.
+
+    """
+
+    # XXX This pattern doesn't catch all subtleties of a Firefox version (like 32.5 isn't valid).
+    # This regex is intended to assign numbers. Then checks are done by attrs and
+    # __attrs_post_init__()
+    _VALID_ENOUGH_VERSION_PATTERN = re.compile(r"""
+        ^(?P<major_number>\d+)
+        \.(?P<minor_number>\d+)
+        (\.(?P<patch_number>\d+))?
+        (
+            (?P<is_nightly>a1)
+            |(?P<is_aurora_or_devedition>a2)
+            |b(?P<beta_number>\d+)
+            |(?P<is_esr>esr)
+        )?
+        -?(build(?P<build_number>\d+))?$""", re.VERBOSE)
+
+    _ALL_VERSION_NUMBERS_TYPES = (
+        'major_number', 'minor_number', 'patch_number', 'beta_number',
+    )
+
+    _OPTIONAL_NUMBERS = BaseVersion._OPTIONAL_NUMBERS + ('beta_number', 'build_number')
+
+    build_number = attr.ib(type=int, converter=strictly_positive_int_or_none, default=None)
+    beta_number = attr.ib(type=int, converter=strictly_positive_int_or_none, default=None)
+    is_nightly = attr.ib(type=bool, default=False)
+    is_aurora_or_devedition = attr.ib(type=bool, default=False)
+    is_esr = attr.ib(type=bool, default=False)
+    version_type = attr.ib(init=False, default=attr.Factory(_find_type, takes_self=True))
+
+    def __attrs_post_init__(self):
+        """Ensure attributes are sane all together."""
+        if self.minor_number == 0 and self.patch_number == 0:
+            raise PatternNotMatchedError(
+                self, pattern='Minor number and patch number cannot be both equal to 0'
+            )
+
+        if self.minor_number != 0 and self.patch_number is None:
+            raise PatternNotMatchedError(
+                self, pattern='Patch number cannot be undefined if minor number is greater than 0'
+            )
+
+        if self.beta_number is not None and self.patch_number is not None:
+            raise PatternNotMatchedError(
+                self, pattern='Beta number and patch number cannot be both defined'
+            )
+
+        if self.patch_number is not None and self.is_nightly:
+            raise PatternNotMatchedError(
+                self, pattern='Patch number cannot be defined on a nightly version'
+            )
+
+        if self.patch_number is not None and self.is_aurora_or_devedition:
+            raise PatternNotMatchedError(
+                self, pattern='Patch number cannot be defined on an aurora version'
+            )
+
+    @classmethod
+    def parse(cls, version_string):
+        """Construct an object representing a valid Firefox version number."""
+        return super(GeckoVersion, cls).parse(
+            version_string, regex_groups=('is_nightly', 'is_aurora_or_devedition', 'is_esr')
+        )
+
+    @property
+    def is_beta(self):
+        """Return `True` if `FirefoxVersion` was built with a string matching a beta version."""
+        return self.beta_number is not None
+
+    @property
+    def is_release(self):
+        """Return `True` if `FirefoxVersion` was built with a string matching a release version."""
+        return not (self.is_nightly or self.is_aurora_or_devedition or self.is_beta or self.is_esr)
+
+    def __str__(self):
+        """Implement string representation.
+
+        Computes a new string based on the given attributes.
+        """
+        string = super(GeckoVersion, self).__str__()
+
+        if self.is_nightly:
+            string = '{}a1'.format(string)
+        elif self.is_aurora_or_devedition:
+            string = '{}a2'.format(string)
+        elif self.is_beta:
+            string = '{}b{}'.format(string, self.beta_number)
+        elif self.is_esr:
+            string = '{}esr'.format(string)
+
+        if self.build_number is not None:
+            string = '{}build{}'.format(string, self.build_number)
+
+        return string
+
+    def __eq__(self, other):
+        """Implement `==` operator.
+
+        A version is considered equal to another if all numbers match and if they are of the same
+        `VersionType`. Like said in `VersionType`, release and ESR are considered equal (if they
+        share the same numbers). If a version contains a build number but not the other, the build
+        number won't be considered in the comparison.
+
+        Examples:
+            .. code-block:: python
+
+                assert GeckoVersion.parse('60.0') == GeckoVersion.parse('60.0')
+                assert GeckoVersion.parse('60.0') == GeckoVersion.parse('60.0esr')
+                assert GeckoVersion.parse('60.0') == GeckoVersion.parse('60.0build1')
+                assert GeckoVersion.parse('60.0build1') == GeckoVersion.parse('60.0build1')
+
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('61.0')
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('60.1.0')
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('60.0.1')
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('60.0a1')
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('60.0a2')
+                assert GeckoVersion.parse('60.0') != GeckoVersion.parse('60.0b1')
+                assert GeckoVersion.parse('60.0build1') != GeckoVersion.parse('60.0build2')
+
+        """
+        return super(GeckoVersion, self).__eq__(other)
+
+    def _compare(self, other):
+        """Compare this release with another.
+
+        Returns:
+            0 if equal
+            < 0 is this precedes the other
+            > 0 if the other precedes this
+
+        """
+        if isinstance(other, str):
+            other = GeckoVersion.parse(other)
+        elif not isinstance(other, GeckoVersion):
+            raise ValueError('Cannot compare "{}", type not supported!'.format(other))
+
+        difference = super(GeckoVersion, self)._compare(other)
+        if difference != 0:
+            return difference
+
+        channel_difference = self._compare_version_type(other)
+        if channel_difference != 0:
+            return channel_difference
+
+        if self.is_beta and other.is_beta:
+            beta_difference = self.beta_number - other.beta_number
+            if beta_difference != 0:
+                return beta_difference
+
+        # Build numbers are a special case. We might compare a regular version number
+        # (like "32.0b8") versus a release build (as in "32.0b8build1"). As a consequence,
+        # we only compare build_numbers when we both have them.
+        try:
+            return self.build_number - other.build_number
+        except TypeError:
+            pass
+
+        return 0
+
+    def _compare_version_type(self, other):
+        return self.version_type.compare(other.version_type)
+
+
+class _VersionWithEdgeCases(GeckoVersion):
+    def __attrs_post_init__(self):
+        for edge_case in self._RELEASED_EDGE_CASES:
+            if all(
+                getattr(self, number_type) == edge_case.get(number_type, None)
+                for number_type in self._ALL_VERSION_NUMBERS_TYPES
+            ):
+                if self.build_number is None:
+                    return
+                elif self.build_number == edge_case.get('build_number', None):
+                    return
+
+        super(_VersionWithEdgeCases, self).__attrs_post_init__()
+
+
+class FirefoxVersion(_VersionWithEdgeCases):
+    """Class that validates and handles Firefox version numbers."""
+
+    _RELEASED_EDGE_CASES = ({
+        'major_number': 33,
+        'minor_number': 1,
+        'build_number': 1,
+    }, {
+        'major_number': 33,
+        'minor_number': 1,
+        'build_number': 2,
+    }, {
+        'major_number': 33,
+        'minor_number': 1,
+        'build_number': 3,
+    }, {
+        'major_number': 38,
+        'minor_number': 0,
+        'patch_number': 5,
+        'beta_number': 1,
+        'build_number': 1,
+    }, {
+        'major_number': 38,
+        'minor_number': 0,
+        'patch_number': 5,
+        'beta_number': 1,
+        'build_number': 2,
+    }, {
+        'major_number': 38,
+        'minor_number': 0,
+        'patch_number': 5,
+        'beta_number': 2,
+        'build_number': 1,
+    }, {
+        'major_number': 38,
+        'minor_number': 0,
+        'patch_number': 5,
+        'beta_number': 3,
+        'build_number': 1,
+    })
+
+
+class DeveditionVersion(GeckoVersion):
+    """Class that validates and handles Devedition after it became an equivalent to beta."""
+
+    # No edge case were shipped
+
+    def __attrs_post_init__(self):
+        """Ensure attributes are sane all together."""
+        if (
+            (not self.is_beta) or
+            (self.major_number < 54) or
+            (self.major_number == 54 and self.beta_number < 11)
+        ):
+            raise PatternNotMatchedError(
+                self, pattern='Devedition as a product must be a beta >= 54.0b11'
+            )
+
+
+class FennecVersion(_VersionWithEdgeCases):
+    """Class that validates and handles Fennec (Firefox for Android) version numbers."""
+
+    _RELEASED_EDGE_CASES = ({
+        'major_number': 33,
+        'minor_number': 1,
+        'build_number': 1,
+    }, {
+        'major_number': 33,
+        'minor_number': 1,
+        'build_number': 2,
+    }, {
+        'major_number': 38,
+        'minor_number': 0,
+        'patch_number': 5,
+        'beta_number': 4,
+        'build_number': 1,
+    })
+
+    def __attrs_post_init__(self):
+        """Ensure attributes are sane all together."""
+        # Versions matching 68.Xa1, 68.XbN, or simply 68.X are expected since bug 1523402. The
+        # latter is needed because of the version.txt of beta
+        if (
+            self.major_number == 68 and
+            self.minor_number > 0 and
+            self.patch_number is None
+        ):
+            return
+
+        if self.major_number >= 69:
+            raise PatternNotMatchedError(self, pattern='Last Fennec version is 68')
+
+        super(FennecVersion, self).__attrs_post_init__()
+
+
+class ThunderbirdVersion(_VersionWithEdgeCases):
+    """Class that validates and handles Thunderbird version numbers."""
+
+    _RELEASED_EDGE_CASES = ({
+        'major_number': 45,
+        'minor_number': 1,
+        'beta_number': 1,
+        'build_number': 1,
+    }, {
+        'major_number': 45,
+        'minor_number': 2,
+        'build_number': 1,
+    }, {
+        'major_number': 45,
+        'minor_number': 2,
+        'build_number': 2,
+    }, {
+        'major_number': 45,
+        'minor_number': 2,
+        'beta_number': 1,
+        'build_number': 2,
+    })
+
+
+class GeckoSnapVersion(GeckoVersion):
+    """Class that validates and handles Gecko's Snap version numbers.
+
+    Snap is a Linux packaging format developped by Canonical. Valid numbers are like "63.0b7-1",
+    "1" stands for "build1". Release Engineering set this scheme at the beginning of Snap and now
+    we can't rename published snap to the regular pattern like "63.0b7-build1".
+    """
+
+    # Our Snaps are recent enough to not list any edge case, yet.
+
+    # Differences between this regex and the one in GeckoVersion:
+    #   * no a2
+    #   * no "build"
+    #   * but mandatory dash and build number.
+    # Example: 63.0b7-1
+    _VALID_ENOUGH_VERSION_PATTERN = re.compile(r"""
+        ^(?P<major_number>\d+)
+        \.(?P<minor_number>\d+)
+        (\.(?P<patch_number>\d+))?
+        (
+            (?P<is_nightly>a1)
+            |b(?P<beta_number>\d+)
+            |(?P<is_esr>esr)
+        )?
+        -(?P<build_number>\d+)$""", re.VERBOSE)
+
+    def __str__(self):
+        """Implement string representation.
+
+        Returns format like "63.0b7-1"
+        """
+        string = super(GeckoSnapVersion, self).__str__()
+        return string.replace('build', '-')
diff --git a/third_party/python/mozilla_version/mozilla_version/maven.py b/third_party/python/mozilla_version/mozilla_version/maven.py
new file mode 100644
index 0000000000..91cecb3431
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/maven.py
@@ -0,0 +1,56 @@
+"""Defines characteristics of a Maven version at Mozilla."""
+
+import attr
+import re
+
+from mozilla_version.version import BaseVersion
+
+
+@attr.s(frozen=True, cmp=False, hash=True)
+class MavenVersion(BaseVersion):
+    """Class that validates and handles Maven version numbers.
+
+    At Mozilla, Maven packages are used in projects like "GeckoView" or "Android-Components".
+    """
+
+    is_snapshot = attr.ib(type=bool, default=False)
+
+    _VALID_ENOUGH_VERSION_PATTERN = re.compile(r"""
+        ^(?P<major_number>\d+)
+        \.(?P<minor_number>\d+)
+        (\.(?P<patch_number>\d+))?
+        (?P<is_snapshot>-SNAPSHOT)?$""", re.VERBOSE)
+
+    @classmethod
+    def parse(cls, version_string):
+        """Construct an object representing a valid Maven version number."""
+        return super(MavenVersion, cls).parse(version_string, regex_groups=('is_snapshot', ))
+
+    def __str__(self):
+        """Implement string representation.
+
+        Computes a new string based on the given attributes.
+        """
+        string = super(MavenVersion, self).__str__()
+
+        if self.is_snapshot:
+            string = '{}-SNAPSHOT'.format(string)
+
+        return string
+
+    def _compare(self, other):
+        if isinstance(other, str):
+            other = MavenVersion.parse(other)
+        elif not isinstance(other, MavenVersion):
+            raise ValueError('Cannot compare "{}", type not supported!'.format(other))
+
+        difference = super(MavenVersion, self)._compare(other)
+        if difference != 0:
+            return difference
+
+        if not self.is_snapshot and other.is_snapshot:
+            return 1
+        elif self.is_snapshot and not other.is_snapshot:
+            return -1
+        else:
+            return 0
diff --git a/third_party/python/mozilla_version/mozilla_version/parser.py b/third_party/python/mozilla_version/mozilla_version/parser.py
new file mode 100644
index 0000000000..d3a6ef6bb6
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/parser.py
@@ -0,0 +1,48 @@
+"""Defines parser helpers."""
+
+from mozilla_version.errors import MissingFieldError
+
+
+def get_value_matched_by_regex(field_name, regex_matches, string):
+    """Ensure value stored in regex group exists."""
+    try:
+        value = regex_matches.group(field_name)
+        if value is not None:
+            return value
+    except IndexError:
+        pass
+
+    raise MissingFieldError(string, field_name)
+
+
+def does_regex_have_group(regex_matches, group_name):
+    """Return a boolean depending on whether a regex group is matched."""
+    try:
+        return regex_matches.group(group_name) is not None
+    except IndexError:
+        return False
+
+
+def positive_int(val):
+    """Parse `val` into a positive integer."""
+    if isinstance(val, float):
+        raise ValueError('"{}" must not be a float'.format(val))
+    val = int(val)
+    if val >= 0:
+        return val
+    raise ValueError('"{}" must be positive'.format(val))
+
+
+def positive_int_or_none(val):
+    """Parse `val` into either `None` or a positive integer."""
+    if val is None:
+        return val
+    return positive_int(val)
+
+
+def strictly_positive_int_or_none(val):
+    """Parse `val` into either `None` or a strictly positive integer."""
+    val = positive_int_or_none(val)
+    if val is None or val > 0:
+        return val
+    raise ValueError('"{}" must be strictly positive'.format(val))
diff --git a/third_party/python/mozilla_version/mozilla_version/version.py b/third_party/python/mozilla_version/mozilla_version/version.py
new file mode 100644
index 0000000000..1f78bec590
--- /dev/null
+++ b/third_party/python/mozilla_version/mozilla_version/version.py
@@ -0,0 +1,177 @@
+"""Defines common characteristics of a version at Mozilla."""
+
+import attr
+import re
+
+from enum import Enum
+
+from mozilla_version.errors import MissingFieldError, PatternNotMatchedError
+from mozilla_version.parser import (
+    get_value_matched_by_regex,
+    does_regex_have_group,
+    positive_int,
+    positive_int_or_none
+)
+
+
+@attr.s(frozen=True, cmp=False, hash=True)
+class BaseVersion(object):
+    """Class that validates and handles general version numbers."""
+
+    major_number = attr.ib(type=int, converter=positive_int)
+    minor_number = attr.ib(type=int, converter=positive_int)
+    patch_number = attr.ib(type=int, converter=positive_int_or_none, default=None)
+
+    _MANDATORY_NUMBERS = ('major_number', 'minor_number')
+    _OPTIONAL_NUMBERS = ('patch_number', )
+    _ALL_NUMBERS = _MANDATORY_NUMBERS + _OPTIONAL_NUMBERS
+
+    _VALID_ENOUGH_VERSION_PATTERN = re.compile(r"""
+        ^(?P<major_number>\d+)
+        \.(?P<minor_number>\d+)
+        (\.(?P<patch_number>\d+))?$""", re.VERBOSE)
+
+    @classmethod
+    def parse(cls, version_string, regex_groups=()):
+        """Construct an object representing a valid version number."""
+        regex_matches = cls._VALID_ENOUGH_VERSION_PATTERN.match(version_string)
+
+        if regex_matches is None:
+            raise PatternNotMatchedError(version_string, cls._VALID_ENOUGH_VERSION_PATTERN)
+
+        kwargs = {}
+
+        for field in cls._MANDATORY_NUMBERS:
+            kwargs[field] = get_value_matched_by_regex(field, regex_matches, version_string)
+        for field in cls._OPTIONAL_NUMBERS:
+            try:
+                kwargs[field] = get_value_matched_by_regex(field, regex_matches, version_string)
+            except MissingFieldError:
+                pass
+
+        for regex_group in regex_groups:
+            kwargs[regex_group] = does_regex_have_group(regex_matches, regex_group)
+
+        return cls(**kwargs)
+
+    def __str__(self):
+        """Implement string representation.
+
+        Computes a new string based on the given attributes.
+        """
+        semvers = [str(self.major_number), str(self.minor_number)]
+        if self.patch_number is not None:
+            semvers.append(str(self.patch_number))
+
+        return '.'.join(semvers)
+
+    def __eq__(self, other):
+        """Implement `==` operator."""
+        return self._compare(other) == 0
+
+    def __ne__(self, other):
+        """Implement `!=` operator."""
+        return self._compare(other) != 0
+
+    def __lt__(self, other):
+        """Implement `<` operator."""
+        return self._compare(other) < 0
+
+    def __le__(self, other):
+        """Implement `<=` operator."""
+        return self._compare(other) <= 0
+
+    def __gt__(self, other):
+        """Implement `>` operator."""
+        return self._compare(other) > 0
+
+    def __ge__(self, other):
+        """Implement `>=` operator."""
+        return self._compare(other) >= 0
+
+    def _compare(self, other):
+        """Compare this release with another.
+
+        Returns:
+            0 if equal
+            < 0 is this precedes the other
+            > 0 if the other precedes this
+
+        """
+        if isinstance(other, str):
+            other = BaseVersion.parse(other)
+        elif not isinstance(other, BaseVersion):
+            raise ValueError('Cannot compare "{}", type not supported!'.format(other))
+
+        for field in ('major_number', 'minor_number', 'patch_number'):
+            this_number = getattr(self, field)
+            this_number = 0 if this_number is None else this_number
+            other_number = getattr(other, field)
+            other_number = 0 if other_number is None else other_number
+
+            difference = this_number - other_number
+
+            if difference != 0:
+                return difference
+
+        return 0
+
+
+class VersionType(Enum):
+    """Enum that sorts types of versions (e.g.: nightly, beta, release, esr).
+
+    Supports comparison. `ESR` is considered higher than `RELEASE` (even if they technically have
+    the same codebase). For instance: 60.0.1 < 60.0.1esr but 61.0 > 60.0.1esr.
+    This choice has a practical use case: if you have a list of Release and ESR version, you can
+    easily extract one kind or the other thanks to the VersionType.
+
+    Examples:
+        .. code-block:: python
+
+            assert VersionType.NIGHTLY == VersionType.NIGHTLY
+            assert VersionType.ESR > VersionType.RELEASE
+
+    """
+
+    NIGHTLY = 1
+    AURORA_OR_DEVEDITION = 2
+    BETA = 3
+    RELEASE = 4
+    ESR = 5
+
+    def __eq__(self, other):
+        """Implement `==` operator."""
+        return self.compare(other) == 0
+
+    def __ne__(self, other):
+        """Implement `!=` operator."""
+        return self.compare(other) != 0
+
+    def __lt__(self, other):
+        """Implement `<` operator."""
+        return self.compare(other) < 0
+
+    def __le__(self, other):
+        """Implement `<=` operator."""
+        return self.compare(other) <= 0
+
+    def __gt__(self, other):
+        """Implement `>` operator."""
+        return self.compare(other) > 0
+
+    def __ge__(self, other):
+        """Implement `>=` operator."""
+        return self.compare(other) >= 0
+
+    def compare(self, other):
+        """Compare this `VersionType` with anotherself.
+
+        Returns:
+            0 if equal
+            < 0 is this precedes the other
+            > 0 if the other precedes this
+
+        """
+        return self.value - other.value
+
+    __hash__ = Enum.__hash__