fix: Show content warning changes when viewing status edits (#1148)

Previous code only ran the status content through the diff engine, so
changes to the content warning / spoiler text were ignored.

Fixes #1144

app/src/main/java/app/pachli/components/viewthread/edits/ViewEditsAdapter.kt

@@ -41,6 +41,7 @@ import com.google.android.material.color.MaterialColors
 import org.xml.sax.XMLReader
 
 class ViewEditsAdapter(
+    context: Context,
     private val edits: List<StatusEdit>,
     private val animateEmojis: Boolean,
     private val useBlurhash: Boolean,
@@ -55,6 +56,8 @@ class ViewEditsAdapter(
     /** Size of medium text in this theme, in px */
     private var mediumTextSizePx: Float = 0f
 
+    private val pachliTagHandler = PachliTagHandler(context)
+
     override fun onCreateViewHolder(
         parent: ViewGroup,
         viewType: Int,
@@ -108,16 +111,18 @@ class ViewEditsAdapter(
         } else {
             binding.statusEditContentWarningDescription.show()
             binding.statusEditContentWarningSeparator.show()
-            binding.statusEditContentWarningDescription.text = edit.spoilerText.emojify(
-                edit.emojis,
-                binding.statusEditContentWarningDescription,
-                animateEmojis,
-            )
+            binding.statusEditContentWarningDescription.text = edit.spoilerText
+                .parseAsMastodonHtml(pachliTagHandler)
+                .emojify(
+                    edit.emojis,
+                    binding.statusEditContentWarningDescription,
+                    animateEmojis,
+                )
         }
 
         val emojifiedText = edit
             .content
-            .parseAsMastodonHtml(PachliTagHandler(context))
+            .parseAsMastodonHtml(pachliTagHandler)
             .emojify(edit.emojis, binding.statusEditContent, animateEmojis)
 
         setClickableText(binding.statusEditContent, emojifiedText, emptyList(), emptyList(), listener)

app/src/main/java/app/pachli/components/viewthread/edits/ViewEditsFragment.kt

@@ -138,6 +138,7 @@ class ViewEditsFragment :
                         binding.initialProgressBar.hide()
 
                         binding.recyclerView.adapter = ViewEditsAdapter(
+                            context = requireContext(),
                             edits = uiState.edits,
                             animateEmojis = animateEmojis,
                             useBlurhash = useBlurhash,

app/src/main/java/app/pachli/components/viewthread/edits/ViewEditsViewModel.kt

@@ -105,9 +105,13 @@ class ViewEditsViewModel @Inject constructor(private val api: MastodonApi) : Vie
                 )
                 val processor = OptimisticXMLProcessor()
                 processor.setCoalesce(true)
-                val output = HtmlDiffOutput()
+                val spoilerDiff = HtmlDiffOutput()
+                val contentDiff = HtmlDiffOutput()
 
                 try {
+                    var currentSpoilerText = loader.load("<div>${sortedEdits[0].spoilerText}</div>")
+                    var previousSpoilerText = loader.load("<div>${sortedEdits[1].spoilerText}</div>")
+
                     // The XML processor expects `br` to be closed
                     var currentContent =
                         loader.load(sortedEdits[0].content.replace("<br>", "<br/>"))
@@ -115,12 +119,16 @@ class ViewEditsViewModel @Inject constructor(private val api: MastodonApi) : Vie
                         loader.load(sortedEdits[1].content.replace("<br>", "<br/>"))
 
                     for (i in 1 until sortedEdits.size) {
-                        processor.diff(previousContent, currentContent, output)
+                        processor.diff(previousSpoilerText, currentSpoilerText, spoilerDiff)
+                        processor.diff(previousContent, currentContent, contentDiff)
                         sortedEdits[i - 1] = sortedEdits[i - 1].copy(
-                            content = output.xml.toString(),
+                            spoilerText = spoilerDiff.xml.toString().removePrefix("<div/>"),
+                            content = contentDiff.xml.toString(),
                         )
 
                         if (i < sortedEdits.size - 1) {
+                            currentSpoilerText = previousSpoilerText
+                            previousSpoilerText = loader.load(sortedEdits[i + 1].spoilerText)
                             currentContent = previousContent
                             previousContent = loader.load(
                                 sortedEdits[i + 1].content.replace("<br>", "<br/>"),