Fixed Android Resolver when run in a Gradle project.

If a parent directory containing a Unity project also contained
a settings.gradle (i.e Gradle project) the Android Resolver would
fail with:

PlayServicesResolver.scripts.download_artifacts.gradle
is not part of the build defined by settings file...

This fixes the issue by creating a Gradle project in the temporary
directory used by the Android Resolver to run the
download_artifacts.gradle script.

Fixes #278

Bug: 141749513
Change-Id: Ic6394b7bd0e7a4f9a3ffde33e1390a2a2d437a22

Author: Stewart Miles

build.gradle

@@ -1027,7 +1027,7 @@ task cleanPackageManagerTests() {
 
 task testDownloadArtifacts(type: GradleBuild) {
   description "Run tests for the download_artifacts.gradle script."
-  buildFile "source/PlayServicesResolver/scripts/download_artifacts_test.gradle"
+  dir "source/PlayServicesResolver/scripts"
 }
 
 task testPackageUploader(type: Exec) {

settings.gradle

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2019 Google Inc. 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.
+ */
+
+rootProject.name = "playServicesResolver"

source/PlayServicesResolver/PlayServicesResolver.csproj

@@ -87,6 +87,9 @@
     <EmbeddedResource Include="scripts\download_artifacts.gradle">
       <Link>scripts\download_artifacts.gradle</Link>
     </EmbeddedResource>
+    <EmbeddedResource Include="scripts\settings.gradle">
+      <Link>scripts\settings.gradle</Link>
+    </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\VersionHandler\VersionHandler.csproj">

source/PlayServicesResolver/scripts/build.gradle

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2019 Google Inc. 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.
+ */
+
+apply from: "download_artifacts_test.gradle"

source/PlayServicesResolver/scripts/download_artifacts_test.gradle

@@ -76,7 +76,8 @@ project.ext {
   outputDir = new File(System.getProperty("user.dir"),
                        "download_artifacts_test_output")
 
-  // Gradle file under test.
+  // Gradle project under test.
+  srcSettingsFile = new File(scriptDirectory, "settings.gradle")
   srcBuildFile = new File(scriptDirectory, "download_artifacts.gradle")
   buildFile = new File(outputDir, srcBuildFile.name)
 
@@ -123,7 +124,7 @@ task copyTestScript(
     type: Copy,
     dependsOn: createDirectoryTask(project.ext.outputDir)) {
   description "Copy the test script into the test project"
-  from srcBuildFile
+  from srcBuildFile, srcSettingsFile
   into outputDir
 }
 

source/PlayServicesResolver/scripts/settings.gradle

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2019 Google Inc. 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.
+ */
+
+rootProject.name = "androidResolver"
+

source/PlayServicesResolver/src/GradleResolver.cs

@@ -252,11 +252,19 @@ private void GradleResolution(
 
             // Extract the gradle wrapper and build script.
             if (!(gradleWrapper.Extract(PlayServicesResolver.logger) &&
-                  EmbeddedResource.ExtractResources(typeof(GradleResolver).Assembly,
-                                                    new KeyValuePair<string, string>[] {
-                                                        new KeyValuePair<string, string>(
-                                                            null, buildScript),
-                                                    }, PlayServicesResolver.logger))) {
+                  EmbeddedResource.ExtractResources(
+                      typeof(GradleResolver).Assembly,
+                      new KeyValuePair<string, string>[] {
+                          new KeyValuePair<string, string>(null, buildScript),
+                          // Copies the settings.gradle file into this folder to mark it as a Gradle
+                          // project. Without the settings.gradle file, Gradle will search up all
+                          // parent directories for a settings.gradle and prevent execution of the
+                          // download_artifacts.gradle script if a settings.gradle is found.
+                          new KeyValuePair<string, string>(
+                              PlayServicesResolver.EMBEDDED_RESOURCES_NAMESPACE + "settings.gradle",
+                              Path.GetFullPath(Path.Combine(gradleWrapper.BuildDirectory,
+                                                            "settings.gradle"))),
+                      }, PlayServicesResolver.logger))) {
                 PlayServicesResolver.Log(String.Format(
                         "Failed to extract {0} and {1} from assembly {2}",
                         gradleWrapper.Executable, buildScript,