De-duplicate building Spannable on Android

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/common/IntConstants.kt

@@ -0,0 +1,14 @@
+package com.facebook.react.common
+
+/**
+ * General-purpose integer constants
+ */
+internal object IntConstants {
+  /**
+   * Some types have built-in support for representing a "missing" or "unset" value, for example
+   * NaN in the case of floating point numbers or null in the case of object references. Integers
+   * don't have such a special value. When an integer represent an inherently non-negative value,
+   * we use a special negative value to mark it as "unset".
+   */
+  const val UNSET: Int = -1
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/common/assets/ReactFontManager.java

@@ -15,6 +15,8 @@
 import androidx.annotation.Nullable;
 import androidx.core.content.res.ResourcesCompat;
 import com.facebook.infer.annotation.Nullsafe;
+import com.facebook.react.common.IntConstants;
+
 import java.util.HashMap;
 import java.util.Map;
 
@@ -167,8 +169,6 @@ public static class TypefaceStyle {
 
     public static final int BOLD = 700;
     public static final int NORMAL = 400;
-    public static final int UNSET = -1;
-
     private static final int MIN_WEIGHT = 1;
     private static final int MAX_WEIGHT = 1000;
 
@@ -177,11 +177,11 @@ public static class TypefaceStyle {
 
     public TypefaceStyle(int weight, boolean italic) {
       mItalic = italic;
-      mWeight = weight == UNSET ? NORMAL : weight;
+      mWeight = weight == IntConstants.UNSET ? NORMAL : weight;
     }
 
     public TypefaceStyle(int style) {
-      if (style == UNSET) {
+      if (style == IntConstants.UNSET) {
         style = Typeface.NORMAL;
       }
 
@@ -194,12 +194,12 @@ public TypefaceStyle(int style) {
      * existing weight bit in `style` will be used.
      */
     public TypefaceStyle(int style, int weight) {
-      if (style == UNSET) {
+      if (style == IntConstants.UNSET) {
         style = Typeface.NORMAL;
       }
 
       mItalic = (style & Typeface.ITALIC) != 0;
-      mWeight = weight == UNSET ? (style & Typeface.BOLD) != 0 ? BOLD : NORMAL : weight;
+      mWeight = weight == IntConstants.UNSET ? (style & Typeface.BOLD) != 0 ? BOLD : NORMAL : weight;
     }
 
     public int getNearestStyle() {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/config/ReactFeatureFlags.java

@@ -185,4 +185,7 @@ public class ReactFeatureFlags {
 
   /** When enabled, the default value of the position style property is relative. */
   public static boolean positionRelativeDefault = false;
+
+  /** Enables the new unified {@link android.text.Spannable} building logic. */
+  public static boolean enableSpannableBuildingUnification = false;
 }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/text/BasicTextAttributeProvider.kt

@@ -0,0 +1,41 @@
+package com.facebook.react.views.text
+
+import com.facebook.react.uimanager.ReactAccessibilityDelegate
+
+/**
+ * Interface for an entity providing basic text attributes of a text node/fragment. "Basic" means
+ * that they can be provided trivially, without processing the parent element.
+ */
+internal interface BasicTextAttributeProvider {
+  val role: ReactAccessibilityDelegate.Role?
+
+  val accessibilityRole: ReactAccessibilityDelegate.AccessibilityRole?
+
+  val isBackgroundColorSet: Boolean
+
+  val backgroundColor: Int
+
+  val isColorSet: Boolean
+
+  val color: Int
+
+  val fontStyle: Int
+
+  val fontWeight: Int
+
+  val fontFamily: String?
+
+  val fontFeatureSettings: String?
+
+  val isUnderlineTextDecorationSet: Boolean
+
+  val isLineThroughTextDecorationSet: Boolean
+
+  val textShadowOffsetDx: Float
+
+  val textShadowOffsetDy: Float
+
+  val textShadowRadius: Float
+
+  val textShadowColor: Int
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/text/CustomStyleSpan.java

@@ -14,6 +14,7 @@
 import android.text.style.MetricAffectingSpan;
 import androidx.annotation.Nullable;
 import com.facebook.infer.annotation.Nullsafe;
+import com.facebook.react.common.IntConstants;
 import com.facebook.react.common.assets.ReactFontManager;
 
 @Nullsafe(Nullsafe.Mode.LOCAL)
@@ -61,11 +62,11 @@ public void updateMeasureState(TextPaint paint) {
   }
 
   public int getStyle() {
-    return mStyle == ReactFontManager.TypefaceStyle.UNSET ? Typeface.NORMAL : mStyle;
+    return mStyle == IntConstants.UNSET ? Typeface.NORMAL : mStyle;
   }
 
   public int getWeight() {
-    return mWeight == ReactFontManager.TypefaceStyle.UNSET
+    return mWeight == IntConstants.UNSET
         ? ReactFontManager.TypefaceStyle.NORMAL
         : mWeight;
   }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/text/EffectiveTextAttributeProvider.kt

@@ -0,0 +1,19 @@
+package com.facebook.react.views.text
+
+import com.facebook.react.common.IntConstants.UNSET
+
+/**
+ * Interface for an entity providing effective text attributes of a text node/fragment
+ */
+internal interface EffectiveTextAttributeProvider : BasicTextAttributeProvider {
+  val textTransform: TextTransform
+
+  val effectiveLetterSpacing: Float
+
+  /**
+   * @return The effective font size, or [UNSET] if not set
+   */
+  val effectiveFontSize: Int
+
+  val effectiveLineHeight: Float
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/text/HierarchicTextAttributeProvider.kt

@@ -0,0 +1,54 @@
+package com.facebook.react.views.text
+
+import com.facebook.react.common.IntConstants
+
+/**
+ * Implementation of [EffectiveTextAttributeProvider] that provides effective text
+ * attributes based on a [ReactBaseTextShadowNode] instance and its parent.
+ */
+internal class HierarchicTextAttributeProvider(
+  private val textShadowNode: ReactBaseTextShadowNode,
+  private val parentTextAttributes: TextAttributes?,
+  private val textAttributes: TextAttributes
+) : EffectiveTextAttributeProvider, BasicTextAttributeProvider by textShadowNode {
+  override val textTransform: TextTransform
+    get() = textAttributes.textTransform
+
+  override val effectiveLetterSpacing: Float
+    get() {
+      val letterSpacing = textAttributes.effectiveLetterSpacing
+
+      val isParentLetterSpacingDifferent =
+        parentTextAttributes == null || parentTextAttributes.effectiveLetterSpacing != letterSpacing
+
+      return if (!letterSpacing.isNaN() && isParentLetterSpacingDifferent) {
+        letterSpacing
+      } else {
+        Float.NaN
+      }
+    }
+
+  override val effectiveFontSize: Int
+    get() {
+      val fontSize = textAttributes.effectiveFontSize
+
+      return if (parentTextAttributes == null || parentTextAttributes.effectiveFontSize != fontSize) {
+        fontSize
+      } else {
+        IntConstants.UNSET
+      }
+    }
+
+  override val effectiveLineHeight: Float
+    get() {
+      val lineHeight = textAttributes.effectiveLineHeight
+      val isParentLineHeightDifferent =
+        parentTextAttributes == null || parentTextAttributes.effectiveLineHeight != lineHeight
+
+      return if (!lineHeight.isNaN() && isParentLineHeightDifferent) {
+        lineHeight
+      } else {
+        Float.NaN
+      }
+    }
+}