Fix double indentation in Elvis chains (#416)

Summary: This is consistent with other binary operators, and prevents a strange second indent in Elvis chains. Pull Request resolved: #416 Reviewed By: strulovich Differential Revision: D49260663 Pulled By: hick209 fbshipit-source-id: 21feb4fb57700bb93ba01aec43a2e7da7d2afa57
facebook · Sep 14, 2023 · ccc2b74 · ccc2b74
1 parent a06e353
commit ccc2b74
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Showing 2 changed files with 69 additions and 12 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
@@ -1207,20 +1207,31 @@ class KotlinInputAstVisitor(
     val leftMostExpression = parts.first()
     visit(leftMostExpression.left)
     for (leftExpression in parts) {
-      when (leftExpression.operationToken) {
-        KtTokens.RANGE -> {}
-        KtTokens.ELVIS -> builder.breakOp(Doc.FillMode.INDEPENDENT, " ", expressionBreakIndent)
-        else -> builder.space()
-      }
-      builder.token(leftExpression.operationReference.text)
       val isFirst = leftExpression === leftMostExpression
-      if (isFirst) {
-        builder.open(expressionBreakIndent)
-      }
+
       when (leftExpression.operationToken) {
-        KtTokens.RANGE -> {}
-        KtTokens.ELVIS -> builder.space()
-        else -> builder.breakOp(Doc.FillMode.UNIFIED, " ", ZERO)
+        KtTokens.RANGE -> {
+          if (isFirst) {
+            builder.open(expressionBreakIndent)
+          }
+          builder.token(leftExpression.operationReference.text)
+        }
+        KtTokens.ELVIS -> {
+          if (isFirst) {
+            builder.open(expressionBreakIndent)
+          }
+          builder.breakOp(Doc.FillMode.UNIFIED, " ", ZERO)
+          builder.token(leftExpression.operationReference.text)
+          builder.space()
+        }
+        else -> {
+          builder.space()
+          if (isFirst) {
+            builder.open(expressionBreakIndent)
+          }
+          builder.token(leftExpression.operationReference.text)
+          builder.breakOp(Doc.FillMode.UNIFIED, " ", ZERO)
+        }
       }
       visit(leftExpression.right)
     }

diff --git a/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt b/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt
@@ -4379,6 +4379,52 @@ class FormatterTest {
               .trimMargin(),
           deduceMaxWidth = true)
 
+  @Test
+  fun `chain of Elvis operator`() =
+      assertFormatted(
+          """
+        |---------------------------
+        |fun f() {
+        |  return option1()
+        |      ?: option2()
+        |      ?: option3()
+        |      ?: option4()
+        |      ?: option5()
+        |}
+        |"""
+              .trimMargin(),
+          deduceMaxWidth = true)
+
+  @Test
+  fun `Elvis operator mixed with plus operator breaking on plus`() =
+      assertFormatted(
+          """
+        |------------------------
+        |fun f() {
+        |  return option1()
+        |      ?: option2() +
+        |          option3()
+        |      ?: option4() +
+        |          option5()
+        |}
+        |"""
+              .trimMargin(),
+          deduceMaxWidth = true)
+
+  @Test
+  fun `Elvis operator mixed with plus operator breaking on elvis`() =
+      assertFormatted(
+          """
+        |---------------------------------
+        |fun f() {
+        |  return option1()
+        |      ?: option2() + option3()
+        |      ?: option4() + option5()
+        |}
+        |"""
+              .trimMargin(),
+          deduceMaxWidth = true)
+
   @Test
   fun `handle comments in the middle of calling chain`() =
       assertFormatted(