removed copying cellFormatter to DisplayConfiguration of nested dataframes in conversion to HTML

Author: Jolanrensen

core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/io/html.kt

@@ -179,17 +179,17 @@ internal fun AnyFrame.toHtmlData(
         val renderConfig = configuration.copy(decimalFormat = format)
         val contents = values.map { row ->
             val value = col[row]
-//            val dfLikeContent = value.toDataFrameLikeOrNull()
-//            if (dfLikeContent != null) {
-//                val df = dfLikeContent.df()
-//                if (df.isEmpty()) {
-//                    HtmlContent("", null)
-//                } else {
-//                    val id = nextTableId()
-//                    queue += RenderingQueueItem(df, id, dfLikeContent.configuration(defaultConfiguration))
-//                    DataFrameReference(id, df.size)
-//                }
-//            } else {
+            val dfLikeContent = value.toDataFrameLikeOrNull()
+            if (dfLikeContent != null) {
+                val df = dfLikeContent.df()
+                if (df.isEmpty()) {
+                    HtmlContent("", null)
+                } else {
+                    val id = nextTableId()
+                    queue += RenderingQueueItem(df, id, dfLikeContent.configuration(defaultConfiguration))
+                    DataFrameReference(id, df.size)
+                }
+            } else {
                 val html = formatter.format(
                     value = downsizeBufferedImageIfNeeded(value, renderConfig),
                     renderer = cellRenderer,
@@ -232,7 +232,7 @@ internal fun AnyFrame.toHtmlData(
                     ?.entries
                     ?.joinToString(";") { "${it.key}:${it.value}" }
                 HtmlContent(html, style)
-//            }
+            }
         }
         val nested = if (col is ColumnGroup<*>) {
             col.columns().map {
@@ -275,7 +275,7 @@ private fun Any?.toDataFrameLikeOrNull(): DataFrameLike? =
     when (this) {
         is AnyFrame -> {
             object : DataFrameLike {
-                override fun configuration(default: DisplayConfiguration) = default
+                override fun configuration(default: DisplayConfiguration) = default.copy(cellFormatter = null)
 
                 override fun df(): AnyFrame = this@toDataFrameLikeOrNull
             }

core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/api/format.kt

@@ -2,10 +2,10 @@ package org.jetbrains.kotlinx.dataframe.api
 
 import io.kotest.matchers.shouldBe
 import io.kotest.matchers.shouldNotBe
-import org.jetbrains.kotlinx.dataframe.alsoDebug
 import org.jetbrains.kotlinx.dataframe.api.FormattingDsl.blue
 import org.jetbrains.kotlinx.dataframe.api.FormattingDsl.red
 import org.jetbrains.kotlinx.dataframe.api.FormattingDsl.rgb
+import org.jetbrains.kotlinx.dataframe.io.DataFrameHtmlData
 import org.jetbrains.kotlinx.dataframe.io.DisplayConfiguration
 import org.jetbrains.kotlinx.dataframe.samples.api.TestBase
 import org.jetbrains.kotlinx.dataframe.samples.api.age
@@ -314,6 +314,7 @@ class FormatTests : TestBase() {
         formatted::class.simpleName shouldBe "FormattedFrame"
     }
 
+    // Issue #982
     @Suppress("ktlint:standard:argument-list-wrapping")
     @Test
     fun `formatting a column shouldn't affect nested columns with the same name`() {
@@ -331,11 +332,12 @@ class FormatTests : TestBase() {
             .group("city").into("cityGroup")
             .rename("cityCopy").into("city")
 
-        df.alsoDebug()
+        val formatted = df.format("city").with { bold and italic and textColor(green) }
+        val html =
+            formatted.toStandaloneHtml() + // expand the nested dataframes so we can see the difference
+                DataFrameHtmlData(script = "document.querySelectorAll('a.expander').forEach(a => a.click());")
 
-        df.format().with { background(black) }.toStandaloneHtml().openInBrowser()
-
-        // affects city, cityGroup.city, and group[*].city
-        df.format("city").with { bold and italic and textColor(green) }.toStandaloneHtml().openInBrowser()
+        html.toString().split("color:#00ff00").size - 1 shouldBe 12
+        html.toString().split("font-style:italic").size - 1 shouldBe 6
     }
 }