Add failing example

audio-ui/src/debug/java/com/google/android/horologist/audio/ui/TestHarness.kt

@@ -0,0 +1,209 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * 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
+ *
+ *      https://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.
+ */
+
+package com.google.android.horologist.audio.ui
+
+import android.content.res.Configuration
+import android.os.Build
+import android.os.LocaleList
+import android.util.DisplayMetrics
+import android.view.ContextThemeWrapper
+import android.view.View
+import androidx.compose.foundation.isSystemInDarkTheme
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.BoxWithConstraints
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.requiredSize
+import androidx.compose.foundation.layout.size
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalConfiguration
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.platform.LocalFontFamilyResolver
+import androidx.compose.ui.platform.LocalLayoutDirection
+import androidx.compose.ui.text.font.createFontFamilyResolver
+import androidx.compose.ui.unit.Density
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.LayoutDirection
+import androidx.core.os.ConfigurationCompat
+import androidx.core.os.LocaleListCompat
+import kotlin.math.floor
+
+/**
+ * Render [content] in a [Box] within a harness, overriding various device configuration values to
+ * make testing easier.
+ *
+ * @param size if not [DpSize.Unspecified], the [content] will be forced to be drawn with at this
+ * size, overriding [LocalDensity] if necessary to ensure that there is enough space. This
+ * defaults to [DpSize.Unspecified].
+ *
+ * @param darkMode if true, the content will be rendered with dark mode. This defaults to the
+ * current dark mode value as reported by [isSystemInDarkTheme].
+ *
+ * @param locales the list of locales to render the app with. This defaults to the list of locales
+ * returned by [LocalConfiguration.current].
+ *
+ * @param layoutDirection an overriding layout direction. This defaults to `null`, which means
+ * that the layout direction from the [locales] is used instead.
+ *
+ * @param fontScale the font scale to render text at. This defaults to the current
+ * [Density.fontScale].
+ *
+ * @param fontWeightAdjustment the font weight adjustment for fonts. This defaults to the current
+ * [fontWeightAdjustment] (if any). If `null`, the [fontWeightAdjustment] will be left unchanged.
+ */
+@Composable
+fun TestHarness(
+    size: DpSize = DpSize.Unspecified,
+    darkMode: Boolean = isSystemInDarkTheme(),
+    locales: LocaleListCompat = ConfigurationCompat.getLocales(LocalConfiguration.current),
+    layoutDirection: LayoutDirection? = null,
+    fontScale: Float = LocalDensity.current.fontScale,
+    fontWeightAdjustment: Int? =
+        if (Build.VERSION.SDK_INT >= 31) LocalConfiguration.current.fontWeightAdjustment else null,
+    content: @Composable () -> Unit
+) {
+    // Use the DensityForcedSize content wrapper if specified
+    val sizeContentWrapper: @Composable (@Composable () -> Unit) -> Unit =
+        if (size == DpSize.Unspecified) {
+            { it() }
+        } else {
+            { DensityForcedSize(size, it) }
+        }
+
+    // First override the density. Doing this first allows using the resulting density in the
+    // overridden configuration.
+    sizeContentWrapper {
+        // Second, override the configuration, with the current configuration modified by the
+        // given parameters.
+        OverriddenConfiguration(
+            configuration = Configuration().apply {
+                // Initialize from the current configuration
+                updateFrom(LocalConfiguration.current)
+                // Set dark mode directly
+                uiMode = uiMode and Configuration.UI_MODE_NIGHT_MASK.inv() or if (darkMode) {
+                    Configuration.UI_MODE_NIGHT_YES
+                } else {
+                    Configuration.UI_MODE_NIGHT_NO
+                }
+                // Update the locale list
+                if (Build.VERSION.SDK_INT >= 24) {
+                    setLocales(LocaleList.forLanguageTags(locales.toLanguageTags()))
+                } else {
+                    setLocale(locales[0])
+                }
+                // Override densityDpi
+                densityDpi =
+                    floor(LocalDensity.current.density * DisplayMetrics.DENSITY_DEFAULT).toInt()
+                // Override font scale
+                this.fontScale = fontScale
+                // Maybe override fontWeightAdjustment
+                if (Build.VERSION.SDK_INT >= 31 && fontWeightAdjustment != null) {
+                    this.fontWeightAdjustment = fontWeightAdjustment
+                }
+            },
+        ) {
+            // Finally, override the layout direction again if manually specified, potentially
+            // overriding the one from the locale.
+            CompositionLocalProvider(
+                LocalLayoutDirection provides (layoutDirection ?: LocalLayoutDirection.current)
+            ) {
+                content()
+            }
+        }
+    }
+}
+
+/**
+ * Overrides the compositions locals related to the given [configuration].
+ *
+ * There currently isn't a single source of truth for these values, so we update them all
+ * according to the given [configuration].
+ */
+@Composable
+internal fun OverriddenConfiguration(
+    configuration: Configuration,
+    content: @Composable () -> Unit
+) {
+    // We don't override the theme, but we do want to override the configuration and this seems
+    // convenient to do so
+    val newContext = ContextThemeWrapper(LocalContext.current, 0).apply {
+        applyOverrideConfiguration(configuration)
+    }
+
+    CompositionLocalProvider(
+        LocalContext provides newContext,
+        LocalConfiguration provides configuration,
+        LocalLayoutDirection provides
+            if (configuration.layoutDirection == View.LAYOUT_DIRECTION_LTR) {
+                LayoutDirection.Ltr
+            } else {
+                LayoutDirection.Rtl
+            },
+        LocalDensity provides Density(
+            configuration.densityDpi.toFloat() / DisplayMetrics.DENSITY_DEFAULT,
+            configuration.fontScale
+        ),
+        LocalFontFamilyResolver provides createFontFamilyResolver(newContext),
+        content = content
+    )
+}
+
+/**
+ * Render [content] in a [Box] that is forced to have the given [size] without clipping.
+ *
+ * This is only suitable for tests, since this will override [LocalDensity] to ensure that the
+ * [size] is met (as opposed to [Modifier.requiredSize] which will result in clipping).
+ */
+@Composable
+internal fun DensityForcedSize(
+    size: DpSize,
+    content: @Composable () -> Unit
+) {
+    BoxWithConstraints(
+        // Try to set the size naturally, we'll be overriding the density below if this fails
+        modifier = Modifier.size(size)
+    ) {
+        // Compute the minimum density required so that both the requested width and height both
+        // fit
+        val density = LocalDensity.current.density * minOf(
+            maxWidth / maxOf(maxWidth, size.width),
+            maxHeight / maxOf(maxHeight, size.height),
+        )
+        // Configuration requires the density DPI to be an integer, so round down to ensure we
+        // have enough space
+        val densityDpi = floor(density * DisplayMetrics.DENSITY_DEFAULT).toInt()
+
+        CompositionLocalProvider(
+            LocalDensity provides Density(
+                // Override the density with the factor needed to meet both the minimum width and
+                // height requirements, and the configuration override requirements.
+                density = densityDpi.toFloat() / DisplayMetrics.DENSITY_DEFAULT,
+                // Pass through the font scale
+                fontScale = LocalDensity.current.fontScale
+            )
+        ) {
+            Box(
+                // This size will now be guaranteed to be able to match the constraints
+                modifier = Modifier.size(size).fillMaxSize()
+            ) {
+                content()
+            }
+        }
+    }
+}

audio-ui/src/debug/java/com/google/android/horologist/audio/ui/VolumeScreenWithLocale.kt

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2022 The Android Open Source Project
+ *
+ * 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
+ *
+ *      https://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.
+ */
+
+package com.google.android.horologist.audio.ui
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.core.os.LocaleListCompat
+import androidx.wear.compose.material.Scaffold
+import com.google.android.horologist.audio.VolumeState
+import com.google.android.horologist.compose.tools.WearSmallRoundDevicePreview
+import java.util.Locale
+
+@WearSmallRoundDevicePreview
+@Composable
+fun VolumeScreenWithLocale() {
+    val volume = VolumeState(10, 10)
+
+    TestHarness(locales = LocaleListCompat.create(Locale.US)) {
+        Box(modifier = Modifier.fillMaxSize()) {
+            Scaffold(
+                positionIndicator = {
+                    VolumePositionIndicator(
+                        volumeState = { volume.copy(current = 5) },
+                        autoHide = false
+                    )
+                }
+            ) {
+                VolumeWithLabelScreen(
+                    volume = { volume },
+                    increaseVolume = { },
+                    decreaseVolume = { }
+                )
+            }
+        }
+    }
+}