ContentResolverHelper: add tests and proper copyright headers

Signed-off-by: Álvaro Brey Vilas <alvaro.brey@nextcloud.com>

src/androidTest/java/com/owncloud/android/datamodel/ContentResolverHelperTest.kt

@@ -0,0 +1,90 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Álvaro Brey Vilas
+ * Copyright (C) 2021 Álvaro Brey Vilas
+ * Copyright (C) 2021 Nextcloud GmbH
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.owncloud.android.datamodel
+
+import android.content.ContentResolver
+import android.net.Uri
+import android.os.Build
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.filters.SdkSuppress
+import io.mockk.mockk
+import io.mockk.verify
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+class ContentResolverHelperTest {
+
+    companion object {
+        private val URI = Uri.parse("http://foo.bar")
+        private val PROJECTION = arrayOf("Foo")
+        private const val SELECTION = "selection"
+        private const val SORT_COLUMN = "sortColumn"
+        private const val SORT_DIRECTION = ContentResolverHelper.SORT_DIRECTION_ASCENDING
+        private const val SORT_DIRECTION_INT = ContentResolver.QUERY_SORT_DIRECTION_ASCENDING
+        private const val LIMIT = 10
+    }
+
+    @Test
+    @SdkSuppress(minSdkVersion = Build.VERSION_CODES.O)
+    fun contentResolver_onAndroidO_usesNewAPI() {
+        val resolver: ContentResolver = mockk(relaxed = true)
+
+        ContentResolverHelper
+            .queryResolver(resolver, URI, PROJECTION, SELECTION, null, SORT_COLUMN, SORT_DIRECTION, LIMIT)
+
+        verify {
+            resolver.query(
+                URI,
+                PROJECTION,
+                withArg { bundle ->
+                    assertEquals(bundle.getString(ContentResolver.QUERY_ARG_SQL_SELECTION), SELECTION)
+                    assertEquals(bundle.getInt(ContentResolver.QUERY_ARG_LIMIT), LIMIT)
+                    assertEquals(bundle.getString(ContentResolver.QUERY_ARG_SORT_COLUMNS), SORT_COLUMN)
+                    assertEquals(bundle.getInt(ContentResolver.QUERY_ARG_SORT_DIRECTION), SORT_DIRECTION_INT)
+                },
+                null
+            )
+        }
+    }
+
+    @Test
+    @SdkSuppress(maxSdkVersion = Build.VERSION_CODES.N_MR1)
+    fun contentResolver_onOlderAndroid_usesOldAPI() {
+        val resolver: ContentResolver = mockk(relaxed = true)
+
+        ContentResolverHelper
+            .queryResolver(resolver, URI, PROJECTION, SELECTION, null, SORT_COLUMN, SORT_DIRECTION, LIMIT)
+
+        verify {
+            resolver.query(
+                URI,
+                PROJECTION,
+                SELECTION,
+                null,
+                "$SORT_COLUMN $SORT_DIRECTION LIMIT $LIMIT",
+                null
+            )
+        }
+    }
+}

src/main/java/com/owncloud/android/datamodel/ContentResolverHelper.kt

@@ -1,3 +1,23 @@
+/*
+ * Nextcloud Android client application
+ *
+ * @author Álvaro Brey Vilas
+ * Copyright (C) 2021 Álvaro Brey Vilas
+ * Copyright (C) 2021 Nextcloud GmbH
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
 package com.owncloud.android.datamodel
 
 import android.content.ContentResolver