Add Android revision checking.

Part of #76.

PiperOrigin-RevId: 534173459
Change-Id: I3185985adee6256b81bbe7d9106641fe46894c48

rules/BUILD

@@ -13,6 +13,14 @@ alias(
     visibility = ["//visibility:public"],
 )
 
+bzl_library(
+    name = "android_revision_bzl",
+    srcs = [
+        "android_revision.bzl",
+    ],
+    visibility = ["//:__subpackages__"],
+)
+
 bzl_library(
     name = "common_bzl",
     srcs = [
@@ -36,10 +44,10 @@ bzl_library(
         "resources.bzl",
         "utils.bzl",
     ],
+    visibility = ["//:__subpackages__"],
     deps = [
         "//rules/acls:bzl",
         "//rules/android_common:bzl",
         "//rules/flags:bzl",
     ],
-    visibility = ["//:__subpackages__"],
 )

rules/android_revision.bzl

@@ -0,0 +1,88 @@
+# Copyright 2023 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Parse and compare Android revision strings."""
+
+# TODO(katre): support preview versions.
+AndroidRevisionInfo = provider(
+    "Information about Android revision specifications.",
+    fields = {
+        "major": "The major version number",
+        "minor": "The minor version number, or 0 if unset.",
+        "micro": "The micro version number, or 0 if unset.",
+        "version": "The version string.",
+        "dir": "The directory where the revision would exist in an Android SDK.",
+    },
+)
+
+def parse_android_revision(input):
+    """Parse and Android revision string and return an AndroidRevisionInfo.
+
+    Args:
+      input: The raw revision string to parse.
+
+    Returns:
+      An AndroidRevisionInfo provider representing the input.
+    """
+    input = input.strip()
+    parts = input.split(".")
+    if len(parts) < 1:
+        fail("Invalid Android revision %s" % input)
+    major = int(parts[0]) if len(parts) >= 1 else 0
+    minor = int(parts[1]) if len(parts) >= 2 else 0
+    micro = int(parts[2]) if len(parts) >= 3 else 0
+
+    return AndroidRevisionInfo(
+        version = input,
+        dir = input,
+        major = major,
+        minor = minor,
+        micro = micro,
+    )
+
+def _compare_android_revision_field(first, second, name):
+    first_val = getattr(first, name)
+    second_val = getattr(second, name)
+    if first_val > second_val:
+        return first
+    elif first_val < second_val:
+        return second
+    return None
+
+def compare_android_revisions(first, second):
+    """Compares two AndroidRevisionInfo providers and returns the one with the highest version.
+
+    Args:
+      first: The first revision to compare.
+      second: The first revision to compare.
+
+    Returns:
+      The revision with the higher version number, or the first if they are equal.
+    """
+    if first == None and second == None:
+        return None
+    if first != None and second == None:
+        return first
+    if first == None and second != None:
+        return second
+    highest = _compare_android_revision_field(first, second, "major")
+    if highest != None:
+        return highest
+    highest = _compare_android_revision_field(first, second, "minor")
+    if highest != None:
+        return highest
+    highest = _compare_android_revision_field(first, second, "micro")
+    if highest != None:
+        return highest
+    return first

test/rules/android_revision/BUILD

@@ -0,0 +1,84 @@
+# Description:
+#   Tests for the AndroidRevisionInfo provider.
+
+load(":test.bzl", "android_revision_comparision_test", "android_revision_test")
+load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+
+licenses(["notice"])
+
+# Test revision string parsing.
+# buildifier: leave-alone
+android_revision_test(
+    name = "version_1.2.3",
+    input = "1.2.3",
+    expected_major = 1,
+    expected_minor = 2,
+    expected_micro = 3,
+    expected_version = "1.2.3",
+    expected_dir = "1.2.3",
+)
+
+# buildifier: leave-alone
+android_revision_test(
+    name = "micro_missing",
+    input = "1.2",
+    expected_major = 1,
+    expected_minor = 2,
+    expected_micro = 0,
+    expected_version = "1.2",
+    expected_dir = "1.2",
+)
+
+# buildifier: leave-alone
+android_revision_test(
+    name = "minor_missing",
+    input = "1",
+    expected_major = 1,
+    expected_minor = 0,
+    expected_micro = 0,
+    expected_version = "1",
+    expected_dir = "1",
+)
+
+# Test revision comparisions.
+VERSIONS = [
+    ("2.0.0", "1.0.0"),
+    ("12.0.0", "11.0.0"),
+    ("1.1.0", "1.0.0"),
+    ("1.0.1", "1.0.0"),
+    ("1.1.1", "1.0.1"),
+    ("2", "1"),
+    ("2.1", "2"),
+    ("2", "1.0"),
+    # TODO(katre): Re-add when previews are supported.
+    #("1.1.0-rc1", "1.0.0-rc1"),
+    #("1.1.0-alpha1", "1.0.0-rc1"),
+    #("1.0.0", "1.0.0-rc1"),
+    #("1.0.0", "1.0.0-rc2"),
+    #("1.0.0", "1.0.0-alpha1"),
+    #("1.0.0", "1.0.0-alpha2"),
+    #("1.0.0", "1.0.0-beta1"),
+    #("1.0.0", "1.0.0-beta2"),
+    #("1.0.0-rc1", "1.0.0-beta1"),
+    #("1.0.0-beta1", "1.0.0-alpha1"),
+    #("1.0.0-beta1", "1.0.0-alpha2"),
+    #("1.0.0-rc2", "1.0.0-rc1"),
+    #("1.0.0-beta2", "1.0.0-beta1"),
+    #("1.0.0-alpha2", "1.0.0-alpha1"),
+    #("1 rc1", "1 beta1"),
+]
+
+[
+    android_revision_comparision_test(
+        name = "compare_%s_%s" % (higher, lower),
+        higher = higher,
+        lower = lower,
+    )
+    for (higher, lower) in VERSIONS
+]
+
+bzl_library(
+    name = "bzl",
+    srcs = glob(["*.bzl"]),
+    visibility = ["//visibility:private"],
+)

test/rules/android_revision/test.bzl

@@ -0,0 +1,103 @@
+# Copyright 2023 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Bazel rules that test the Android revision parsing.
+
+The following are test rules that can be used to test the AndroidRevisionInfo provider.
+
+android_revision_test: Inspect providers with the given set of expected values.
+"""
+
+load(
+    "//rules:android_revision.bzl",
+    "compare_android_revisions",
+    "parse_android_revision",
+)
+load(
+    "//test/utils:lib.bzl",
+    "asserts",
+    "unittest",
+)
+
+def _android_revision_test_impl(ctx):
+    env = unittest.begin(ctx)
+    input = ctx.attr.input
+    revision = parse_android_revision(input)
+
+    asserts.equals(
+        env,
+        ctx.attr.expected_major,
+        revision.major,
+    )
+    asserts.equals(
+        env,
+        ctx.attr.expected_minor,
+        revision.minor,
+    )
+    asserts.equals(
+        env,
+        ctx.attr.expected_micro,
+        revision.micro,
+    )
+    asserts.equals(
+        env,
+        ctx.attr.expected_version,
+        revision.version,
+    )
+    asserts.equals(
+        env,
+        ctx.attr.expected_dir,
+        revision.dir,
+    )
+
+    return unittest.end(env)
+
+android_revision_test = unittest.make(
+    impl = _android_revision_test_impl,
+    attrs = {
+        "input": attr.string(),
+        "expected_major": attr.int(),
+        "expected_minor": attr.int(),
+        "expected_micro": attr.int(),
+        "expected_version": attr.string(),
+        "expected_dir": attr.string(),
+    },
+)
+
+def _assert_revisions_equal(env, expected, value):
+    asserts.equals(env, expected.major, value.major)
+    asserts.equals(env, expected.minor, value.minor)
+    asserts.equals(env, expected.major, value.major)
+
+def _android_revision_comparision_test_impl(ctx):
+    env = unittest.begin(ctx)
+    higher = parse_android_revision(ctx.attr.higher)
+    lower = parse_android_revision(ctx.attr.lower)
+
+    result = compare_android_revisions(higher, lower)
+    _assert_revisions_equal(
+        env,
+        higher,
+        result,
+    )
+
+    return unittest.end(env)
+
+android_revision_comparision_test = unittest.make(
+    impl = _android_revision_comparision_test_impl,
+    attrs = {
+        "higher": attr.string(),
+        "lower": attr.string(),
+    },
+)