Add tests for painter hint (#190)

Add test for painter hints

core/build.gradle.kts

@@ -11,4 +11,9 @@ private val composeVersion get() = ComposeBuildConfig.composeVersion
 
 dependencies {
     api("org.jetbrains.compose.foundation:foundation-desktop:$composeVersion")
+
+    testImplementation(compose.desktop.uiTestJUnit4)
+    testImplementation(compose.desktop.currentOs) {
+        exclude(group = "org.jetbrains.compose.material")
+    }
 }

core/src/main/kotlin/org/jetbrains/jewel/painter/PainterHint.kt

@@ -19,22 +19,57 @@ import org.w3c.dom.Element
 @Immutable
 sealed interface PainterHint {
 
+    fun canApplyTo(path: String): Boolean = true
+
     /**
      * An empty [PainterHint], it will be ignored.
      */
     companion object None : PainterHint {
 
+        override fun canApplyTo(path: String): Boolean = false
+
         override fun toString(): String = "None"
     }
 }
 
+/**
+ * Mark this [PainterHint] just available with SVG images.
+ */
+@Immutable
+interface SvgPainterHint : PainterHint {
+
+    override fun canApplyTo(path: String): Boolean = path.substringAfterLast('.').lowercase() == "svg"
+}
+
+/**
+ * Mark this [PainterHint] just available with Bitmap images.
+ */
+@Immutable
+interface BitmapPainterHint : PainterHint {
+
+    override fun canApplyTo(path: String): Boolean = when (path.substringAfterLast('.').lowercase()) {
+        "svg", "xml" -> false
+        else -> true
+    }
+}
+
+/**
+ * Mark this [PainterHint] just available with XML images.
+ */
+@Immutable
+interface XmlPainterHint : PainterHint {
+
+    override fun canApplyTo(path: String): Boolean = path.substringAfterLast('.').lowercase() == "xml"
+}
+
 /**
  * A [PainterHint] that modifies the path of the resource being loaded.
  * Usage examples are applying the New UI icon mappings, or picking up
  * dark theme variants of icons.
  */
 @Immutable
 interface PainterPathHint : PainterHint {
+
     /**
      * Replace the entire path with the given value.
      */
@@ -59,7 +94,7 @@ interface PainterResourcePathHint : PainterHint {
  * to SVG resources; it doesn't affect other types of resources.
  */
 @Immutable
-interface PainterSvgPatchHint : PainterHint {
+interface PainterSvgPatchHint : SvgPainterHint {
 
     /**
      * Patch the SVG content.

core/src/main/kotlin/org/jetbrains/jewel/painter/PainterHintsProvider.kt

@@ -3,13 +3,15 @@ package org.jetbrains.jewel.painter
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.Immutable
 import androidx.compose.runtime.staticCompositionLocalOf
+import androidx.compose.ui.platform.LocalDensity
 import org.jetbrains.jewel.IntelliJTheme
 import org.jetbrains.jewel.painter.hints.Dark
+import org.jetbrains.jewel.painter.hints.HiDpi
 
 /**
  * Provides [hints][PainterHint] to a [PainterProvider].
  *
- * @see DarkPainterHintsProvider
+ * @see CommonPainterHintsProvider
  * @see org.jetbrains.jewel.intui.core.IntUiPainterHintsProvider
  * @see org.jetbrains.jewel.intui.standalone.StandalonePainterHintsProvider
  */
@@ -24,12 +26,15 @@ interface PainterHintsProvider {
  * The default [PainterHintsProvider] to load dark theme icon variants.
  * It will provide the [Dark] hint when [LocalIsDarkTheme][org.jetbrains.jewel.LocalIsDarkTheme] is true.
  */
-object DarkPainterHintsProvider : PainterHintsProvider {
+object CommonPainterHintsProvider : PainterHintsProvider {
 
     @Composable
-    override fun hints(path: String): List<PainterHint> = listOf(Dark(IntelliJTheme.isDark))
+    override fun hints(path: String): List<PainterHint> = listOf(
+        HiDpi(LocalDensity.current),
+        Dark(IntelliJTheme.isDark),
+    )
 }
 
 val LocalPainterHintsProvider = staticCompositionLocalOf<PainterHintsProvider> {
-    DarkPainterHintsProvider
+    CommonPainterHintsProvider
 }

core/src/main/kotlin/org/jetbrains/jewel/painter/ResourcePainterProvider.kt

@@ -61,7 +61,7 @@ class ResourcePainterProvider(
     @Composable
     override fun getPainter(vararg hints: PainterHint): State<Painter> {
         val resolvedHints = (hints.toList() + LocalPainterHintsProvider.current.hints(basePath))
-            .filter { it != PainterHint.None }
+            .filter { it.canApplyTo(basePath) }
 
         val cacheKey = resolvedHints.hashCode()
 
@@ -190,24 +190,6 @@ class ResourcePainterProvider(
             rememberAction = { remember(url, density) { it } },
         )
 
-    private fun Document.writeToString(): String {
-        val tf = TransformerFactory.newInstance()
-        val transformer: Transformer
-
-        try {
-            transformer = tf.newTransformer()
-            transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes")
-
-            val writer = StringWriter()
-            transformer.transform(DOMSource(this), StreamResult(writer))
-            return writer.buffer.toString()
-        } catch (e: TransformerException) {
-            error("Unable to render XML document to string: ${e.message}")
-        } catch (e: IOException) {
-            error("Unable to render XML document to string: ${e.message}")
-        }
-    }
-
     @Composable
     private fun <T> tryLoadingResource(
         url: URL,
@@ -231,6 +213,24 @@ class ResourcePainterProvider(
     }
 }
 
+internal fun Document.writeToString(): String {
+    val tf = TransformerFactory.newInstance()
+    val transformer: Transformer
+
+    try {
+        transformer = tf.newTransformer()
+        transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes")
+
+        val writer = StringWriter()
+        transformer.transform(DOMSource(this), StreamResult(writer))
+        return writer.buffer.toString()
+    } catch (e: TransformerException) {
+        error("Unable to render XML document to string: ${e.message}")
+    } catch (e: IOException) {
+        error("Unable to render XML document to string: ${e.message}")
+    }
+}
+
 @Composable
 fun rememberResourcePainterProvider(path: String, iconClass: Class<*>): PainterProvider =
     remember(path, iconClass.classLoader) {

core/src/main/kotlin/org/jetbrains/jewel/painter/hints/HiDpi.kt

@@ -0,0 +1,22 @@
+package org.jetbrains.jewel.painter.hints
+
+import androidx.compose.runtime.Immutable
+import org.jetbrains.jewel.painter.BitmapPainterHint
+import org.jetbrains.jewel.painter.PainterHint
+import org.jetbrains.jewel.painter.PainterSuffixHint
+
+@Immutable
+private object HiDpiImpl : PainterSuffixHint(), BitmapPainterHint {
+
+    override fun suffix(): String = "@2x"
+
+    override fun toString(): String = "HiDpi"
+}
+
+fun HiDpi(isHiDpi: Boolean): PainterHint = if (isHiDpi) {
+    HiDpiImpl
+} else {
+    PainterHint.None
+}
+
+fun HiDpi(density: androidx.compose.ui.unit.Density): PainterHint = HiDpi(density.density > 1)

core/src/main/kotlin/org/jetbrains/jewel/painter/hints/Palette.kt

@@ -33,7 +33,10 @@ private class PaletteImpl(val map: Map<Color, Color>) : PainterSvgPatchHint {
             val alpha = opacity.toFloatOrNull() ?: 1.0f
             val originalColor = tryParseColor(color, alpha) ?: return
             val newColor = pattern[originalColor] ?: return
-            setAttribute(attrName, newColor.copy(alpha = alpha).toRgbaHexString())
+            setAttribute(attrName, newColor.copy(alpha = 1.0f).toRgbaHexString())
+            if (newColor.alpha != alpha) {
+                setAttribute("$attrName-opacity", newColor.alpha.toString())
+            }
         }
     }
 

core/src/main/kotlin/org/jetbrains/jewel/painter/hints/Size.kt

@@ -3,9 +3,10 @@ package org.jetbrains.jewel.painter.hints
 import androidx.compose.runtime.Immutable
 import org.jetbrains.jewel.painter.PainterHint
 import org.jetbrains.jewel.painter.PainterSuffixHint
+import org.jetbrains.jewel.painter.SvgPainterHint
 
 @Immutable
-private class SizeImpl(private val size: String) : PainterSuffixHint() {
+private class SizeImpl(private val size: String) : PainterSuffixHint(), SvgPainterHint {
 
     override fun suffix(): String = buildString {
         append("@")
@@ -26,10 +27,22 @@ private class SizeImpl(private val size: String) : PainterSuffixHint() {
     }
 }
 
-fun Size(size: String?): PainterHint = if (size.isNullOrEmpty()) {
-    PainterHint.None
-} else {
-    SizeImpl(size)
+private val sizeHintValidateRegex = """\d+x\d+""".toRegex()
+
+fun Size(size: String): PainterHint {
+    if (size.isBlank()) return PainterHint.None
+    val trimmed = size.trim()
+    require(sizeHintValidateRegex.matches(trimmed)) {
+        "Size must be in format of <width>x<height>"
+    }
+
+    return SizeImpl(trimmed)
 }
 
-fun Size(width: Int, height: Int): PainterHint = SizeImpl("${width}x$height")
+fun Size(width: Int, height: Int = width): PainterHint {
+    require(width > 0 && height > 0) {
+        "Width and height must be positive"
+    }
+
+    return SizeImpl("${width}x$height")
+}

core/src/test/kotlin/org/jetbrains/jewel/BasicJewelUiTest.kt

@@ -0,0 +1,28 @@
+package org.jetbrains.jewel
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.test.junit4.ComposeContentTestRule
+import androidx.compose.ui.test.junit4.createComposeRule
+import kotlinx.coroutines.runBlocking
+import org.junit.Before
+import org.junit.Rule
+
+open class BasicJewelUiTest {
+
+    @get:Rule
+    val composeRule = createComposeRule()
+
+    @Suppress("ImplicitUnitReturnType")
+    protected fun runComposeTest(
+        composable: @Composable () -> Unit,
+        block: suspend ComposeContentTestRule.() -> Unit,
+    ) = runBlocking {
+        composeRule.setContent(composable)
+        composeRule.block()
+    }
+
+    @Before
+    fun setUpProperties() {
+        System.setProperty("org.jetbrains.jewel.debug", "true")
+    }
+}