Prevent adjacent unary operators from merging

facebook · Jun 8, 2022 · 03b8ddc · 03b8ddc
1 parent e563773
commit 03b8ddc
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Showing 2 changed files with 53 additions and 6 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
@@ -1075,19 +1075,33 @@ class KotlinInputAstVisitor(
     builder.close()
   }
 
-  override fun visitUnaryExpression(expression: KtUnaryExpression) {
+  override fun visitPostfixExpression(expression: KtPostfixExpression) {
     builder.sync(expression)
     builder.block(ZERO) {
-      visit(expression.baseExpression)
-      builder.token(expression.operationReference.text)
+      val baseExpression = expression.baseExpression
+      val operator = expression.operationReference.text
+
+      visit(baseExpression)
+      if (baseExpression is KtPostfixExpression &&
+          baseExpression.operationReference.text.last() == operator.first()) {
+          builder.space()
+      }
+      builder.token(operator)
     }
   }
 
   override fun visitPrefixExpression(expression: KtPrefixExpression) {
     builder.sync(expression)
     builder.block(ZERO) {
-      builder.token(expression.operationReference.text)
-      visit(expression.baseExpression)
+      val baseExpression = expression.baseExpression
+      val operator = expression.operationReference.text
+
+      builder.token(operator)
+      if (baseExpression is KtPrefixExpression &&
+          operator.last() == baseExpression.operationReference.text.first()) {
+          builder.space()
+      }
+      visit(baseExpression)
     }
   }
 

diff --git a/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt b/core/src/test/java/com/facebook/ktfmt/format/FormatterTest.kt
@@ -2834,7 +2834,7 @@ class FormatterTest {
       |""".trimMargin())
 
   @Test
-  fun `Unary expressions`() =
+  fun `Unary prefix expressions`() =
       assertFormatted(
           """
       |fun f() {
@@ -2844,6 +2844,39 @@ class FormatterTest {
       |  +4
       |  ++a
       |  --a
+      |
+      |  + +a
+      |  +-a
+      |  +!a
+      |  -+a
+      |  - -a
+      |  -!a
+      |  !+a
+      |  !a
+      |  ! !a
+      |
+      |  + ++a
+      |  +--a
+      |  -++a
+      |  - --a
+      |  !++a
+      |  !--a
+      |}
+      |""".trimMargin())
+
+  @Test
+  fun `Unary postfix expressions`() =
+      assertFormatted(
+          """
+      |fun f() {
+      |  a!!
+      |  a++
+      |  a--
+      |
+      |  a--!!
+      |  a++!!
+      |
+      |  a!! !!
       |}
       |""".trimMargin())