Android: Fraunces last-line descenders clipped with tight lineHeight (0.86.0, candidate Kotlin regression tests) #59021

package com.facebook.react.views.text.internal.span

import android.graphics.Paint.FontMetricsInt
import org.junit.Assert.assertEquals
import org.junit.Test
import org.junit.runner.RunWith
import org.robolectric.RobolectricTestRunner
import org.robolectric.annotation.Config

@RunWith(RobolectricTestRunner::class)
@Config(manifest = Config.NONE, sdk = [33])
class CustomLineHeightSpanTest {
  private fun metrics() = FontMetricsInt().apply {
    top = -42
    ascent = -38
    descent = 10
    bottom = 12
  }

  @Test
  fun tightFinalLinePreservesFontDescent() {
    val fm = metrics()
    CustomLineHeightSpan(42f).chooseHeight("gyp\ngyp", 4, 7, 0, 42, fm)
    assertEquals(-35, fm.ascent)
    assertEquals(10, fm.descent)
    assertEquals(10, fm.bottom)
    assertEquals(-42, fm.top)
  }

  @Test
  fun tightSingleLinePreservesFontDescent() {
    val fm = metrics()
    CustomLineHeightSpan(42f).chooseHeight("gyp", 0, 3, 0, 0, fm)
    assertEquals(-35, fm.ascent)
    assertEquals(-35, fm.top)
    assertEquals(10, fm.descent)
    assertEquals(10, fm.bottom)
  }

  @Test
  fun interiorLinesKeepDesignedLeadingAndFontBounds() {
    val fm = metrics()
    CustomLineHeightSpan(42f).chooseHeight("gyp\ngyp\ngyp", 4, 8, 0, 42, fm)
    assertEquals(42, fm.descent - fm.ascent)
    assertEquals(-35, fm.ascent)
    assertEquals(7, fm.descent)
    assertEquals(-42, fm.top)
    assertEquals(12, fm.bottom)
  }

  @Test
  fun firstLineKeepsDesignedLeading() {
    val fm = metrics()
    CustomLineHeightSpan(42f).chooseHeight("gyp\ngyp", 0, 4, 0, 0, fm)
    assertEquals(42, fm.descent - fm.ascent)
    assertEquals(-35, fm.top)
    assertEquals(12, fm.bottom)
  }

  @Test
  fun nonNegativeLeadingIsUnchanged() {
    for (height in listOf(48f, 53f)) {
      val fm = metrics()
      CustomLineHeightSpan(height).chooseHeight("gyp", 0, 3, 0, 0, fm)
      assertEquals(height.toInt(), fm.descent - fm.ascent)
      assertEquals(if (height == 48f) 10 else 12, fm.descent)
      assertEquals(fm.descent, fm.bottom)
      assertEquals(fm.ascent, fm.top)
    }
  }

  @Test
  fun fractionalHeightAndOddNegativeLeadingKeepRounding() {
    val fm = metrics()
    CustomLineHeightSpan(42.2f).chooseHeight("gyp", 0, 3, 0, 0, fm)
    assertEquals(-36, fm.ascent)
    assertEquals(10, fm.descent)
    assertEquals(10, fm.bottom)
  }
}