Fix #358 Outlier tooltips: the spout sometimes is too long (boxplot).

Author: OLarionova-HORIS

future_changes.md

@@ -41,3 +41,4 @@
 - Wrong direction in colorbars (legend) [[#204](https://github.com/JetBrains/lets-plot/issues/204)].
 - geom_jitter: show axis tooltips (same as geom_point) [[#412](https://github.com/JetBrains/lets-plot/issues/412)].
 - Memory leak in IDEA caused by a `final void dispose()` method in PlotPanel.
+- Outlier tooltips: the spout sometimes is too long (boxplot) [[#358](https://github.com/JetBrains/lets-plot/issues/358)].

plot-builder/src/commonMain/kotlin/jetbrains/datalore/plot/builder/tooltip/layout/LayoutManager.kt

@@ -295,8 +295,20 @@ class LayoutManager(
                     stemX = targetCoordX
                 }
                 !(canFitLeft || canFitRight) -> {
-                    tooltipX = 0.0
-                    stemX = targetCoordX
+                    when (myPreferredHorizontalAlignment) {
+                        HorizontalAlignment.LEFT -> {
+                            stemX = targetCoordX - hintSize
+                            tooltipX = stemX + stemLength
+                        }
+                        HorizontalAlignment.RIGHT -> {
+                            stemX = targetCoordX + hintSize
+                            tooltipX = stemX - tooltipWidth - stemLength
+                        }
+                        HorizontalAlignment.CENTER -> {
+                            stemX = targetCoordX
+                            tooltipX = targetCoordX - tooltipWidth / 2
+                        }
+                    }
                 }
                 myPreferredHorizontalAlignment == HorizontalAlignment.LEFT && canFitLeft || !canFitRight -> {
                     tooltipX = leftTooltipPlacement.start()

plot-builder/src/jvmTest/kotlin/plot/builder/tooltip/layout/HorizontalTooltipLayoutTest.kt

@@ -6,10 +6,12 @@
 package jetbrains.datalore.plot.builder.tooltip.layout
 
 import jetbrains.datalore.base.geometry.DoubleRectangle
+import jetbrains.datalore.base.geometry.DoubleVector
 import jetbrains.datalore.plot.builder.interact.TestUtil.coord
 import jetbrains.datalore.plot.builder.interact.TestUtil.size
 import jetbrains.datalore.plot.builder.tooltip.layout.LayoutManager.HorizontalAlignment
 import jetbrains.datalore.plot.builder.tooltip.layout.LayoutManager.HorizontalAlignment.LEFT
+import jetbrains.datalore.plot.builder.tooltip.layout.LayoutManager.HorizontalAlignment.RIGHT
 import jetbrains.datalore.plot.builder.tooltip.layout.MeasuredTooltipBuilder.MeasuredTooltipBuilderFactory
 import kotlin.test.Test
 
@@ -197,6 +199,50 @@ internal class HorizontalTooltipLayoutTest : TooltipLayoutTestBase() {
         )
     }
 
+    @Test
+    fun whenThereIsNotEnoughHorizontalSpaceFromBothSides_AndHorizontalAlignmentIsLeft_ShouldAlignTooltipToRightOfTheLeftBorder() {
+        val objectRadius = 200.0
+        val tooltipBuilder = MeasuredTooltipBuilderFactory()
+            .defaultObjectRadius(objectRadius)
+            .defaultTipSize(size(80.0, 80.0))
+
+        val layoutManagerController = createTipLayoutManagerBuilder(VIEWPORT)
+            .addTooltip(tooltipBuilder.horizontal(TOOLTIP_KEY, VIEWPORT.center).buildTooltip())
+            .build()
+
+        arrange(layoutManagerController)
+
+        val stemX = VIEWPORT.center.x - objectRadius
+        assertAllTooltips(
+            expect()
+                .tooltipX(stemX + NORMAL_STEM_LENGTH)
+                .stemCoord(DoubleVector(stemX, VIEWPORT.center.y))
+        )
+    }
+
+    @Test
+    fun whenThereIsNotEnoughHorizontalSpaceFromBothSides_AndHorizontalAlignmentIsRight_ShouldAlignTooltipToLeftOfTheRightBorder() {
+        val objectRadius = 200.0
+        val tipSize = size(80.0, 80.0)
+        val tooltipBuilder = MeasuredTooltipBuilderFactory()
+            .defaultObjectRadius(objectRadius)
+            .defaultTipSize(tipSize)
+
+        val layoutManagerController = createTipLayoutManagerBuilder(VIEWPORT)
+            .preferredHorizontalAlignment(RIGHT)
+            .addTooltip(tooltipBuilder.horizontal(TOOLTIP_KEY, VIEWPORT.center).buildTooltip())
+            .build()
+
+        arrange(layoutManagerController)
+
+        val stemX = VIEWPORT.center.x + objectRadius
+        assertAllTooltips(
+            expect()
+                .tooltipX(stemX - tipSize.x - NORMAL_STEM_LENGTH)
+                .stemCoord(DoubleVector(stemX, VIEWPORT.center.y))
+        )
+    }
+
     companion object {
         private const val IGNORED_KEY = "ignored"
         private const val TOOLTIP_KEY = "tooltip"

plot-builder/src/jvmTest/kotlin/plot/builder/tooltip/layout/TooltipLayoutTestBase.kt

@@ -194,7 +194,7 @@ internal open class TooltipLayoutTestBase {
 
     internal class TipLayoutManagerBuilder(private val myViewport: DoubleRectangle) : TooltipDataProvider {
         private val myTooltipData = ArrayList<MeasuredTooltip>()
-        private val myHorizontalAlignment: HorizontalAlignment = LEFT
+        private var myHorizontalAlignment: HorizontalAlignment = LEFT
         private var myCursor = DoubleVector.ZERO
 
         fun cursor(cursor: DoubleVector): TipLayoutManagerBuilder {
@@ -207,6 +207,11 @@ internal open class TooltipLayoutTestBase {
             return this
         }
 
+        fun preferredHorizontalAlignment(horizontalAlignment: HorizontalAlignment): TipLayoutManagerBuilder {
+            myHorizontalAlignment = horizontalAlignment
+            return this
+        }
+
         fun build(): TipLayoutManagerController {
             return object : TipLayoutManagerController {
                 override fun arrange(): List<PositionedTooltip> =