Extract the Skiko text backend into the ui-skiko module

Move the Skia-backed implementation of ui-text into ui-skiko, leaving
ui-text's nonAndroidMain Skia-free, mirroring the graphics extraction.
ui-text keeps expect/actual delegators resolving a registered
ComposeUiTextImplementation; the org.jetbrains.skia paragraph, font and
text-paint code lives in ui-skiko.

- Paragraph building, intrinsics, char helpers and the font subsystem
  (FontFamilyResolver, font loading, PlatformFont) relocate to ui-skiko.
- The font subsystem is ui-text's own public API with per-platform
  loadTypeface actuals, so the unavoidable public Skia-typed surface
  stays in ui-text's skikoMain compat layer (Skia-free nonAndroidMain ->
  Skia skikoMain -> platform leaves); only the implementation moves.
- ComposeUiSkikoRuntime.registerSkikoComposeImplementation() now wires
  both the graphics and text implementations (plus the temporary
  SkikoGraphicsCompat bridge).

API baselines are regenerated in a later commit.

Author: MatkovIvan

compose/ui/ui-skiko/build.gradle

@@ -76,6 +76,11 @@ androidXMultiplatform {
             dependsOn(nonAndroidTest)
             dependencies {
                 implementation(libs.skikoCurrentOs)
+                implementation(libs.junit)
+                implementation(libs.truth)
+                implementation(project(":internal-testutils-fonts"))
+                implementation(project(":compose:foundation:foundation"))
+                implementation(project(":compose:ui:ui-test-junit4"))
             }
         }
 

…in/androidx/compose/ui/text/Cache.jvm.kt …in/androidx/compose/ui/text/Cache.jvm.ktcompose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/Cache.jvm.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/Cache.jvm.kt compose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/Cache.jvm.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/Cache.jvm.kt

@@ -15,11 +15,6 @@
  */
 package androidx.compose.ui.text
 
-
-/**
- * Get strong (R, L or AL) direction type.
- * See https://www.unicode.org/reports/tr9/
- */
 internal actual fun CodePoint.strongDirectionType(): StrongDirectionType =
     when (getDirectionality()) {
         CharDirectionality.LEFT_TO_RIGHT -> StrongDirectionType.Ltr
@@ -29,6 +24,7 @@ internal actual fun CodePoint.strongDirectionType(): StrongDirectionType =
 
         else -> StrongDirectionType.None
     }
+
 internal actual fun CodePoint.isNeutralDirection(): Boolean =
     when (getDirectionality()) {
         CharDirectionality.OTHER_NEUTRALS,

…roidx/compose/ui/text/CharHelpers.jvm.kt …roidx/compose/ui/text/CharHelpers.jvm.ktcompose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/CharHelpers.jvm.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/CharHelpers.jvm.kt compose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/CharHelpers.jvm.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/CharHelpers.jvm.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2023 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
+ *
+ *      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.
+ */
+
+package androidx.compose.ui.text.font
+
+import androidx.compose.runtime.Stable
+import androidx.compose.ui.text.ExperimentalTextApi
+import androidx.compose.ui.text.platform.JetBrainsRuntimeFontFamilies
+
+/**
+ * Load a [FontFamily] embedded in the JetBrains Runtime. It will return
+ * `null` if the font family isn't embedded in the JetBrains Runtime,
+ * or if using any Java runtime other than the JetBrains Runtime.
+ *
+ * Using this requires the current module to have access to the `sun.font`
+ * APIs, which are closed by default. To open the access to those APIs, you
+ * need to pass this argument to the JVM:
+ * ```
+ * --add-opens java.desktop/sun.font=ALL-UNNAMED
+ * ```
+ *
+ * If the `sun.font` API is not accessible, this will always return `null`.
+ *
+ * @param familyName The case-insensitive font family name to load.
+ * @return the requested font family, if running on the JetBrains Runtime,
+ *     and the `sun.font` API is accessible, and the font family exists in
+ *     the runtime. Otherwise, `null`.
+ */
+@ExperimentalTextApi
+@Stable
+fun EmbeddedFontFamily(familyName: String): FontFamily? =
+    JetBrainsRuntimeFontFamilies.embeddedFamilies[familyName.lowercase()]

compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/font/EmbeddedFontFamily.desktop.kt

@@ -0,0 +1,123 @@
+/*
+ * Copyright 2020 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
+ *
+ *      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.
+ */
+
+package androidx.compose.ui.text.platform
+
+import androidx.compose.ui.InternalComposeUiApi
+import androidx.compose.ui.text.ExperimentalTextApi
+import androidx.compose.ui.text.font.Font
+import androidx.compose.ui.text.font.FontStyle
+import androidx.compose.ui.text.font.FontVariation
+import androidx.compose.ui.text.font.FontWeight
+import java.io.File
+import org.jetbrains.skia.Data
+import org.jetbrains.skia.FontMgr
+import org.jetbrains.skia.FontSlant
+import org.jetbrains.skia.FontStyle as SkFontStyle
+import org.jetbrains.skia.FontWidth
+import org.jetbrains.skia.Typeface as SkTypeface
+
+@OptIn(ExperimentalTextApi::class)
+internal actual fun loadTypeface(font: Font): SkTypeface {
+    if (font !is PlatformFont) {
+        throw IllegalArgumentException("Unsupported font type: $font")
+    }
+    val typeface = when (font) {
+        is ResourceFont -> typefaceResource(font.name)
+        is FileFont -> FontMgr.default.makeFromFile(font.file.toString())
+        is LoadedFont -> FontMgr.default.makeFromData(Data.makeFromBytes(font.data))
+        is SystemFont -> FontMgr.default.matchFamilyStyle(font.identity, font.skFontStyle)
+    } ?: (FontMgr.default.legacyMakeTypeface(font.identity, font.skFontStyle)
+        ?: error("loadTypeface legacyMakeTypeface failed"))
+    return typeface.cloneWithVariationSettings(font.variationSettings)
+}
+
+private fun typefaceResource(resourceName: String): SkTypeface {
+    val contextClassLoader = Thread.currentThread().contextClassLoader!!
+    val resource = contextClassLoader.getResourceAsStream(resourceName)
+        ?: (::typefaceResource.javaClass).getResourceAsStream(resourceName)
+        ?: error("Can't load font from $resourceName")
+
+    val bytes = resource.use { it.readAllBytes() }
+    return FontMgr.default.makeFromData(Data.makeFromBytes(bytes))!!
+}
+
+private val Font.skFontStyle: SkFontStyle
+    get() = SkFontStyle(
+        weight = weight.weight,
+        width = FontWidth.NORMAL,
+        slant = if (style == FontStyle.Italic) FontSlant.ITALIC else FontSlant.UPRIGHT
+    )
+
+internal actual fun currentPlatform(): Platform {
+    val name = System.getProperty("os.name")
+    return when {
+        name.startsWith("Linux") -> Platform.Linux
+        name.startsWith("Win") -> Platform.Windows
+        name == "Mac OS X" -> Platform.MacOS
+        else -> Platform.Unknown
+    }
+}
+
+/**
+ * Creates a Font using a resource name.
+ *
+ * @param resource The resource name in classpath.
+ * @param weight The weight of the font. The system uses this to match a font to a font request that
+ * is given in a [androidx.compose.ui.text.SpanStyle].
+ * @param style The style of the font, normal or italic. The system uses this to match a font to a
+ * font request that is given in a [androidx.compose.ui.text.SpanStyle].
+ * @see FontFamily
+ */
+@OptIn(InternalComposeUiApi::class)
+fun Font(
+    resource: String,
+    weight: FontWeight = FontWeight.Normal,
+    style: FontStyle = FontStyle.Normal
+): Font = ResourceFont(resource, weight, style, FontVariation.Settings())
+
+@OptIn(InternalComposeUiApi::class)
+fun Font(
+    resource: String,
+    weight: FontWeight = FontWeight.Normal,
+    style: FontStyle = FontStyle.Normal,
+    variationSettings: FontVariation.Settings = FontVariation.Settings(weight, style)
+): Font = ResourceFont(resource, weight, style, variationSettings)
+
+/**
+ * Creates a Font using a file path.
+ *
+ * @param file File path to font.
+ * @param weight The weight of the font. The system uses this to match a font to a font request that
+ * is given in a [androidx.compose.ui.text.SpanStyle].
+ * @param style The style of the font, normal or italic. The system uses this to match a font to a
+ * font request that is given in a [androidx.compose.ui.text.SpanStyle].
+ * @see FontFamily
+ */
+@OptIn(InternalComposeUiApi::class)
+fun Font(
+    file: File,
+    weight: FontWeight = FontWeight.Normal,
+    style: FontStyle = FontStyle.Normal
+): Font = FileFont(file, weight, style, FontVariation.Settings())
+
+@OptIn(InternalComposeUiApi::class)
+fun Font(
+    file: File,
+    weight: FontWeight = FontWeight.Normal,
+    style: FontStyle = FontStyle.Normal,
+    variationSettings: FontVariation.Settings = FontVariation.Settings(weight, style)
+): Font = FileFont(file, weight, style, variationSettings)

…mpose/ui/text/platform/AwtFontInterop.kt …mpose/ui/text/platform/AwtFontInterop.ktcompose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/platform/AwtFontInterop.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/platform/AwtFontInterop.kt compose/ui/ui-text/src/desktopMain/kotlin/androidx/compose/ui/text/platform/AwtFontInterop.kt renamed to compose/ui/ui-skiko/src/desktopMain/kotlin/androidx/compose/ui/text/platform/AwtFontInterop.kt

@@ -17,7 +17,6 @@
 package androidx.compose.ui.text.platform
 
 import androidx.compose.ui.text.font.FontFamily
-import androidx.compose.ui.text.font.FontListFontFamily
 import androidx.compose.ui.text.font.FontStyle
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.util.fastDistinctBy
@@ -112,7 +111,7 @@ internal object JetBrainsRuntimeFontFamilies {
                 .distinctBy { (_, font) -> font.file.absolutePath }
                 .groupBy { (familyName, _) -> familyName }
                 .forEach { (identity, fileFonts) ->
-                    val fontFamily = FontListFontFamily(fileFonts.fastMap { it.second })
+                    val fontFamily = FontFamily(fileFonts.fastMap { it.second })
                     embeddedFamilies += identity.lowercase() to fontFamily
                 }
         } finally {