Add a merge function for ComponentPadding

mori-atsushi · Nov 24, 2023 · dce3a7c · dce3a7c
1 parent 6f0bf96
commit dce3a7c
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Showing 3 changed files with 67 additions and 6 deletions.
diff --git a/...tTest/kotlin/com/moriatsushi/compose/stylesheet/component/padding/ComponentPaddingTest.kt b/...tTest/kotlin/com/moriatsushi/compose/stylesheet/component/padding/ComponentPaddingTest.kt
@@ -7,14 +7,12 @@ import androidx.compose.ui.test.junit4.createComposeRule
 import androidx.compose.ui.unit.LayoutDirection
 import androidx.compose.ui.unit.dp
 import androidx.test.ext.junit.runners.AndroidJUnit4
-import com.moriatsushi.compose.stylesheet.component.StyleSheetComponentApi
 import com.moriatsushi.compose.stylesheet.token.Token
 import kotlin.test.assertEquals
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 
-@OptIn(StyleSheetComponentApi::class)
 @RunWith(AndroidJUnit4::class)
 class ComponentPaddingTest {
     @get:Rule
@@ -165,4 +163,54 @@ class ComponentPaddingTest {
             }
         }
     }
+
+    @Test
+    fun testAsPaddingValues_merged() {
+        val paddingValues = PaddingValues(
+            start = 10.dp,
+            top = 20.dp,
+            end = 30.dp,
+            bottom = 40.dp,
+        )
+        val padding1 = ComponentPadding(
+            PaddingValues(
+                start = 10.dp,
+                top = 20.dp,
+                end = 30.dp,
+                bottom = 40.dp,
+            ),
+        )
+        val padding2 = ComponentPadding(
+            start = Token(50.dp),
+            top = Token(60.dp),
+        )
+        val merged1 = padding1.merge(padding2)
+        val merged2 = padding2.merge(padding1)
+
+        composeTestRule.setContent {
+            CompositionLocalProvider(LocalLayoutDirection provides LayoutDirection.Ltr) {
+                assertEquals(
+                    PaddingValues.Absolute(
+                        left = 50.dp,
+                        top = 60.dp,
+                        right = 30.dp,
+                        bottom = 40.dp,
+                    ),
+                    merged1.asPaddingValues(),
+                )
+            }
+
+            CompositionLocalProvider(LocalLayoutDirection provides LayoutDirection.Ltr) {
+                assertEquals(
+                    PaddingValues.Absolute(
+                        left = 10.dp,
+                        top = 20.dp,
+                        right = 30.dp,
+                        bottom = 40.dp,
+                    ),
+                    merged2.asPaddingValues(),
+                )
+            }
+        }
+    }
 }
diff --git a/...ommonMain/kotlin/com/moriatsushi/compose/stylesheet/component/padding/ComponentPadding.kt b/...ommonMain/kotlin/com/moriatsushi/compose/stylesheet/component/padding/ComponentPadding.kt
@@ -15,6 +15,9 @@ import com.moriatsushi.compose.stylesheet.token.value
 
 @Immutable
 sealed class ComponentPadding {
+    internal abstract val values: List<Pair<PaddingSide, Token<Dp>>>
+    internal abstract val paddingValues: PaddingValues?
+
     @Composable
     internal abstract fun asPaddingValues(): PaddingValues
 
@@ -26,6 +29,16 @@ sealed class ComponentPadding {
         right: Token<Dp>? = null,
         left: Token<Dp>? = null,
     ): ComponentPadding
+
+    internal fun merge(other: ComponentPadding): ComponentPadding =
+        if (other.paddingValues != null) {
+            other
+        } else {
+            ComponentPaddingImpl(
+                values = other.values + values,
+                paddingValues = paddingValues,
+            )
+        }
 }
 
 internal fun ComponentPadding(paddingValues: PaddingValues): ComponentPadding =
@@ -50,8 +63,8 @@ internal fun ComponentPadding(
 )
 
 private data class ComponentPaddingImpl(
-    private val values: List<Pair<PaddingSide, Token<Dp>>> = emptyList(),
-    private val paddingValues: PaddingValues? = null,
+    override val values: List<Pair<PaddingSide, Token<Dp>>> = emptyList(),
+    override val paddingValues: PaddingValues? = null,
 ) : ComponentPadding() {
     @Composable
     override fun asPaddingValues(): PaddingValues {
@@ -125,6 +138,6 @@ fun Modifier.componentPadding(padding: ComponentPadding?): Modifier = this.then(
     if (padding != null) Modifier.padding(padding.asPaddingValues()) else Modifier,
 )
 
-private enum class PaddingSide {
+internal enum class PaddingSide {
     Left, Top, Right, Bottom, Start, End,
 }
diff --git a/...c/commonMain/kotlin/com/moriatsushi/compose/stylesheet/component/padding/PaddingSetter.kt b/...c/commonMain/kotlin/com/moriatsushi/compose/stylesheet/component/padding/PaddingSetter.kt
@@ -35,7 +35,7 @@ class PaddingSetter internal constructor() {
 
     operator fun plusAssign(padding: ComponentPadding?) {
         if (padding != null) {
-            value = padding
+            value = value?.merge(padding) ?: padding
         }
     }