Avoid usage of not() and add unit tests.

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/MatrixHomeServerDetails.kt

@@ -11,4 +11,6 @@ data class MatrixHomeServerDetails(
     val url: String,
     val supportsPasswordLogin: Boolean,
     val supportsOidcLogin: Boolean,
-)
+) {
+    val isSupported = supportsPasswordLogin || supportsOidcLogin
+}

libraries/matrix/api/src/test/kotlin/io/element/android/libraries/matrix/api/auth/MatrixHomeServerDetailsTest.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.api.auth
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.matrix.test.auth.aMatrixHomeServerDetails
+import org.junit.Test
+
+class MatrixHomeServerDetailsTest {
+    @Test
+    fun `if homeserver supports oidc, then it is supported`() {
+        val sut = aMatrixHomeServerDetails(
+            supportsOidcLogin = true,
+            supportsPasswordLogin = false,
+        )
+        assertThat(sut.isSupported).isTrue()
+    }
+
+    @Test
+    fun `if homeserver supports password, then it is supported`() {
+        val sut = aMatrixHomeServerDetails(
+            supportsOidcLogin = false,
+            supportsPasswordLogin = true,
+        )
+        assertThat(sut.isSupported).isTrue()
+    }
+
+    @Test
+    fun `if homeserver supports both, then it is supported`() {
+        val sut = aMatrixHomeServerDetails(
+            supportsOidcLogin = true,
+            supportsPasswordLogin = true,
+        )
+        assertThat(sut.isSupported).isTrue()
+    }
+
+    @Test
+    fun `if homeserver supports none, then it is not supported`() {
+        val sut = aMatrixHomeServerDetails(
+            supportsOidcLogin = false,
+            supportsPasswordLogin = false,
+        )
+        assertThat(sut.isSupported).isFalse()
+    }
+}