facebook · lwasyl · Jun 4, 2026 · Jun 4, 2026
diff --git a/core/build.gradle.kts b/core/build.gradle.kts
@@ -134,7 +134,7 @@ kotlin {
 
 ktfmt {
   trailingCommaManagementStrategy.set(
-      com.ncorti.ktfmt.gradle.TrailingCommaManagementStrategy.ONLY_ADD
+      com.ncorti.ktfmt.gradle.TrailingCommaManagementStrategy.ONLY_ADD,
   )
 }
 

diff --git a/core/src/main/java/com/facebook/ktfmt/cli/Main.kt b/core/src/main/java/com/facebook/ktfmt/cli/Main.kt
@@ -73,7 +73,7 @@ class Main(
         result.addAll(
             File(arg).walkTopDown().filter {
               it.isFile && (it.extension == "kt" || it.extension == "kts")
-            }
+            },
         )
       }
       return result

diff --git a/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt b/core/src/main/java/com/facebook/ktfmt/cli/ParsedArgs.kt
@@ -134,7 +134,7 @@ data class ParsedArgs(
               stdinName =
                   parseKeyValueArg("--stdin-name", arg)
                       ?: return ParseResult.Error(
-                          "Found option '${arg}', expected '${"--stdin-name"}=<value>'"
+                          "Found option '${arg}', expected '${"--stdin-name"}=<value>'",
                       )
           arg.startsWith("--") -> return ParseResult.Error("Unexpected option: $arg")
           arg.startsWith("@") -> return ParseResult.Error("Unexpected option: $arg")
@@ -148,7 +148,7 @@ data class ParsedArgs(
           val filesExceptStdin = fileNames - "-"
           return ParseResult.Error(
               "Cannot read from stdin and files in same run. Found stdin specifier '-'" +
-                  " and files ${filesExceptStdin.joinToString(", ")} "
+                  " and files ${filesExceptStdin.joinToString(", ")} ",
           )
         }
       } else if (stdinName != null) {
@@ -164,7 +164,7 @@ data class ParsedArgs(
               stdinName,
               editorConfig,
               quiet,
-          )
+          ),
       )
     }
 

diff --git a/core/src/main/java/com/facebook/ktfmt/format/Formatter.kt b/core/src/main/java/com/facebook/ktfmt/format/Formatter.kt
@@ -132,7 +132,7 @@ object Formatter {
     val tokenRangeSet =
         kotlinInput.characterRangesToTokenRanges(ImmutableList.of(Range.closedOpen(0, code.length)))
     return WhitespaceTombstones.replaceTombstoneWithTrailingWhitespace(
-        JavaOutput.applyReplacements(code, javaOutput.getFormatReplacements(tokenRangeSet))
+        JavaOutput.applyReplacements(code, javaOutput.getFormatReplacements(tokenRangeSet)),
     )
   }
 

diff --git a/core/src/main/java/com/facebook/ktfmt/format/FormattingOptions.kt b/core/src/main/java/com/facebook/ktfmt/format/FormattingOptions.kt
@@ -191,7 +191,7 @@ data class FormattingOptions(
 
     /** @see FormattingOptions.trailingCommaManagementStrategy */
     fun trailingCommaManagementStrategy(
-        trailingCommaManagementStrategy: TrailingCommaManagementStrategy
+        trailingCommaManagementStrategy: TrailingCommaManagementStrategy,
     ): Builder = apply { this.trailingCommaManagementStrategy = trailingCommaManagementStrategy }
 
     /** @see FormattingOptions.removeUnusedImports */

diff --git a/core/src/main/java/com/facebook/ktfmt/format/KotlinInput.kt b/core/src/main/java/com/facebook/ktfmt/format/KotlinInput.kt
@@ -84,7 +84,7 @@ class KotlinInput(private val text: String, file: KtFile) : Input() {
           characterRangeToTokenRange(
               characterRange.lowerEndpoint(),
               characterRange.upperEndpoint() - characterRange.lowerEndpoint(),
-          )
+          ),
       )
     }
     return tokenRangeSet
@@ -107,7 +107,7 @@ class KotlinInput(private val text: String, file: KtFile) : Input() {
               "error: invalid length %d, offset + length (%d) is outside the file",
               length,
               requiredLength,
-          )
+          ),
       )
     }
     val expandedLength =

diff --git a/core/src/main/java/com/facebook/ktfmt/format/KotlinInputAstVisitor.kt b/core/src/main/java/com/facebook/ktfmt/format/KotlinInputAstVisitor.kt
@@ -2283,7 +2283,7 @@ class KotlinInputAstVisitor(
 
   /** Example `a: String` which is part of `(a: String, b: String)` */
   override fun visitDestructuringDeclarationEntry(
-      multiDeclarationEntry: KtDestructuringDeclarationEntry
+      multiDeclarationEntry: KtDestructuringDeclarationEntry,
   ) {
     builder.sync(multiDeclarationEntry)
     declareOne(
@@ -2690,7 +2690,7 @@ class KotlinInputAstVisitor(
             child is PsiComment -> continue
             child is KtScript && importListEmpty -> OpsBuilder.BlankLineWanted.PRESERVE
             else -> OpsBuilder.BlankLineWanted.YES
-          }
+          },
       )
 
       visit(child)

diff --git a/core/src/main/java/com/facebook/ktfmt/format/MultilineStringFormatter.kt b/core/src/main/java/com/facebook/ktfmt/format/MultilineStringFormatter.kt
@@ -150,11 +150,11 @@ class MultilineStringFormatter(val continuationIndentSize: Int) {
                           expression.getParentOfType<KtStringTemplateExpression>(strict = false) !=
                               null,
                       commentsBetweenStringAndTrimCall = comments,
-                  )
+                  ),
               )
             }
           }
-        }
+        },
     )
     return strings.toList()
   }

diff --git a/core/src/main/java/com/facebook/ktfmt/format/ParseError.kt b/core/src/main/java/com/facebook/ktfmt/format/ParseError.kt
@@ -21,7 +21,7 @@ import org.jetbrains.kotlin.com.intellij.psi.PsiElement
 
 class ParseError(val errorDescription: String, val lineColumn: LineColumn) :
     IllegalArgumentException(
-        "${lineColumn.line + 1}:${lineColumn.column + 1}: error: $errorDescription"
+        "${lineColumn.line + 1}:${lineColumn.column + 1}: error: $errorDescription",
     ) {
 
   constructor(

diff --git a/core/src/main/java/com/facebook/ktfmt/format/RedundantElementManager.kt b/core/src/main/java/com/facebook/ktfmt/format/RedundantElementManager.kt
@@ -68,7 +68,7 @@ object RedundantElementManager {
             redundantImportDetector.takeReferenceExpression(expression)
             super.visitReferenceExpression(expression)
           }
-        }
+        },
     )
 
     val elementsToRemove =
@@ -106,7 +106,7 @@ object RedundantElementManager {
             trailingCommaSuggestor.takeElement(element)
             super.visitElement(element)
           }
-        }
+        },
     )
 
     val suggestionElements = trailingCommaSuggestor.getTrailingCommaSuggestions()

diff --git a/core/src/main/java/com/facebook/ktfmt/format/TrailingCommas.kt b/core/src/main/java/com/facebook/ktfmt/format/TrailingCommas.kt
@@ -99,8 +99,8 @@ object TrailingCommas {
       if (!element.textContains('\n')) {
         return // Only suggest trailing commas where there is already a line break
       }
-      if (list.items.size <= 1) {
-        return // Never insert commas to single-element lists
+      if (list.items.isEmpty()) {
+        return // Never insert commas to empty lists
       }
       if (list.trailingComma != null) {
         return // Never insert a comma if there already is one somehow

diff --git a/core/src/main/java/com/facebook/ktfmt/kdoc/KDocCommentsHelper.kt b/core/src/main/java/com/facebook/ktfmt/kdoc/KDocCommentsHelper.kt
@@ -54,7 +54,7 @@ class KDocCommentsHelper(private val lineSeparator: String, private val maxLineL
             convertMarkup = false
             nestedListIndent = 4
             optimal = false // Use greedy line breaking for predictability.
-          }
+          },
       )
 
   override fun rewrite(tok: Tok, maxWidth: Int, column0: Int): String {

diff --git a/core/src/main/java/com/facebook/ktfmt/kdoc/KDocFormattingOptions.kt b/core/src/main/java/com/facebook/ktfmt/kdoc/KDocFormattingOptions.kt
@@ -69,7 +69,7 @@ class KDocFormattingOptions(
       if (value < 3) {
         error(
             "Nested list indent must be at least 3; if list items are only indented 2 spaces they " +
-                "will not be rendered as list items"
+                "will not be rendered as list items",
         )
       }
       field = value

diff --git a/core/src/test/java/com/facebook/ktfmt/cli/EditorConfigResolverTest.kt b/core/src/test/java/com/facebook/ktfmt/cli/EditorConfigResolverTest.kt
@@ -64,7 +64,7 @@ class EditorConfigResolverTest {
         [*.c]
         max_line_length = 80
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -81,7 +81,7 @@ class EditorConfigResolverTest {
         [*.kt]
         max_line_length = 80
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -98,7 +98,7 @@ class EditorConfigResolverTest {
         [*.kt]
         max_line_length = off
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -115,7 +115,7 @@ class EditorConfigResolverTest {
         [*.kt]
         indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -132,7 +132,7 @@ class EditorConfigResolverTest {
         [*.kt]
         indent_size = tab
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -150,7 +150,7 @@ class EditorConfigResolverTest {
         indent_size = tab
         tab_width = 8
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -167,7 +167,7 @@ class EditorConfigResolverTest {
         [*.kt]
         ij_kotlin_indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -185,7 +185,7 @@ class EditorConfigResolverTest {
         indent_size = 2
         ij_kotlin_indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -202,7 +202,7 @@ class EditorConfigResolverTest {
         [*.kt]
         ij_continuation_indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -219,7 +219,7 @@ class EditorConfigResolverTest {
         [*.kt]
         ij_kotlin_continuation_indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -237,7 +237,7 @@ class EditorConfigResolverTest {
         ij_continuation_indent_size = 6
         ij_kotlin_continuation_indent_size = 3
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -254,7 +254,7 @@ class EditorConfigResolverTest {
         [*.kt]
         ktfmt_trailing_comma_management_strategy = only_add
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -272,7 +272,7 @@ class EditorConfigResolverTest {
         [*.kt]
         ktfmt_trailing_comma_management_strategy = whatever
         """
-            .trimIndent()
+            .trimIndent(),
     )
 
     val file = root.resolve("src/main/kotlin/Example.kt")
@@ -292,7 +292,7 @@ class EditorConfigResolverTest {
         [src/**/*.kts]
         max_line_length = 120
         """
-            .trimIndent()
+            .trimIndent(),
     )
     val rootOptions =
         Formatter.GOOGLE_FORMAT.copy(
@@ -309,7 +309,7 @@ class EditorConfigResolverTest {
         max_line_length = 200
         ktfmt_trailing_comma_management_strategy = only_add
         """
-            .trimIndent()
+            .trimIndent(),
     )
     val mainOptions =
         Formatter.GOOGLE_FORMAT.copy(
@@ -329,7 +329,7 @@ class EditorConfigResolverTest {
         ij_continuation_indent_size = 2
         max_line_length = 300
         """
-            .trimIndent()
+            .trimIndent(),
     )
     val testOptions =
         Formatter.GOOGLE_FORMAT.copy(

diff --git a/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt b/core/src/test/java/com/facebook/ktfmt/cli/ParsedArgsTest.kt
@@ -221,7 +221,7 @@ class ParsedArgsTest {
                 formattingOptions = Formatter.GOOGLE_FORMAT,
                 dryRun = true,
                 setExitIfChanged = true,
-            )
+            ),
         )
   }
 
@@ -234,7 +234,7 @@ class ParsedArgsTest {
             parseResultOk(
                 fileNames = listOf("File.kt"),
                 formattingOptions = Formatter.KOTLINLANG_FORMAT,
-            )
+            ),
         )
   }
 
@@ -270,7 +270,7 @@ class ParsedArgsTest {
             stdinName,
             editorConfig,
             quiet,
-        )
+        ),
     )
   }
 }
-Original file line number
+Diff line change
@@ Expand Up / @@ -134,7 +134,7 @@ kotlin { @@
     ktfmt {
       trailingCommaManagementStrategy.set(
-          com.ncorti.ktfmt.gradle.TrailingCommaManagementStrategy.ONLY_ADD
+          com.ncorti.ktfmt.gradle.TrailingCommaManagementStrategy.ONLY_ADD,
       )
     }
@@ Expand Down @@