Preserve semicolons in enums with members but no entries

Inspired by facebook#425
nreid260 · Dec 16, 2023 · bf26e68 · bf26e68
1 parent c0511df
commit bf26e68
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Showing 3 changed files with 82 additions and 5 deletions.
diff --git a/core/src/main/java/com/facebook/ktfmt/format/KotlinInputAstVisitor.kt b/core/src/main/java/com/facebook/ktfmt/format/KotlinInputAstVisitor.kt
@@ -44,6 +44,7 @@ import org.jetbrains.kotlin.psi.KtBreakExpression
 import org.jetbrains.kotlin.psi.KtCallExpression
 import org.jetbrains.kotlin.psi.KtCallableReferenceExpression
 import org.jetbrains.kotlin.psi.KtCatchClause
+import org.jetbrains.kotlin.psi.KtClass
 import org.jetbrains.kotlin.psi.KtClassBody
 import org.jetbrains.kotlin.psi.KtClassInitializer
 import org.jetbrains.kotlin.psi.KtClassLiteralExpression
@@ -1943,7 +1944,8 @@ class KotlinInputAstVisitor(
  emitBracedBlock(body) { children ->
  val (enumEntries, nonEnumEntryMembers) = children.partition { it is KtEnumEntry }
 
- if (enumEntries.isNotEmpty()) {
+ val parent = body.parent
+ if (parent is KtClass && parent.isEnum()) {
  builder.block(ZERO) {
  builder.breakOp(Doc.FillMode.UNIFIED, "", ZERO)
  for (value in enumEntries) {

diff --git a/core/src/main/java/com/facebook/ktfmt/format/RedundantSemicolonDetector.kt b/core/src/main/java/com/facebook/ktfmt/format/RedundantSemicolonDetector.kt
@@ -17,6 +17,7 @@
 package com.facebook.ktfmt.format
 
 import org.jetbrains.kotlin.com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.psi.KtClass
 import org.jetbrains.kotlin.psi.KtContainerNodeForControlStructureBody
 import org.jetbrains.kotlin.psi.KtDeclaration
 import org.jetbrains.kotlin.psi.KtEnumEntry
@@ -51,13 +52,21 @@ internal class RedundantSemicolonDetector {
  if (parent is KtStringTemplateExpression || parent is KtStringTemplateEntry) {
  return false
  }
- if (parent is KtEnumEntry &&
- parent.siblings(forward = true, withItself = false).any { it is KtDeclaration }) {
- return false
+
+ if (parent is KtEnumEntry) {
+ // Terminationg comma of an enum entry list.
+ return !hasFollowingDeclaration(parent)
  }
 
- val prevLeaf = element.prevLeaf(false)
+ val grandparent = parent.parent
  val prevConcreteSibling = element.getPrevSiblingIgnoringWhitespaceAndComments()
+ if (grandparent is KtClass && grandparent.isEnum()) {
+ val isFirstToken = prevConcreteSibling?.text == "{"
+ // Terminationg comma of an empty enum entry list.
+ return !isFirstToken || !hasFollowingDeclaration(element)
+ }
+
+ val prevLeaf = element.prevLeaf(false)
  if ((prevConcreteSibling is KtIfExpression || prevConcreteSibling is KtWhileExpression) &&
  prevLeaf is KtContainerNodeForControlStructureBody &&
  prevLeaf.text.isEmpty()) {
@@ -78,4 +87,8 @@ internal class RedundantSemicolonDetector {
 
  return true
  }
+
+ private fun hasFollowingDeclaration(element: PsiElement): Boolean {
+ return element.siblings(forward = true, withItself = false).any { it is KtDeclaration }
+ }
 }
diff --git a/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt b/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt
@@ -4649,6 +4649,68 @@ class FormatterTest {
  |"""
  .trimMargin())
 
+ @Test
+ fun `semicolon is removed from empty enum`() {
+ val code =
+ """
+ |enum class SingleSemi {
+ | ;
+ |}
+ |
+ |enum class MultSemi {
+ | // a
+ | ;
+ | // b
+ | ;
+ | // c
+ | ;
+ |}
+ |"""
+ .trimMargin()
+ val expected =
+ """
+ |enum class SingleSemi {}
+ |
+ |enum class MultSemi {
+ | // a
+ |
+ | // b
+ |
+ | // c
+ |
+ |}
+ |"""
+ .trimMargin()
+ assertThatFormatting(code).isEqualTo(expected)
+ }
+
+ @Test
+ fun `semicolon management in enum with no entries but other members`() {
+ val code =
+ """
+ |enum class Empty {
+ | ;
+ |
+ | fun f() {}
+ | ;
+ | fun g() {}
+ |}
+ |"""
+ .trimMargin()
+ val expected =
+ """
+ |enum class Empty {
+ | ;
+ |
+ | fun f() {}
+ |
+ | fun g() {}
+ |}
+ |"""
+ .trimMargin()
+ assertThatFormatting(code).isEqualTo(expected)
+ }
+
  @Test
  fun `handle varargs and spread operator`() =
  assertFormatted(