Fix false -ve on else with single line binary or chained call

CHANGELOG.md

@@ -40,6 +40,7 @@ At this point in time, it is not yet decided what the next steps will be. Ktlint
 * Do not merge an annotated expression body with the function signature even if it fits on a single line ([#2043](https://github.com/pinterest/ktlint/issues/2043))
 * Ignore property with name `serialVersionUID` in `property-naming` ([#2045](https://github.com/pinterest/ktlint/issues/2045))
 * Prevent incorrect reporting of violations in case a nullable function type reference exceeds the maximum line length `parameter-list-wrapping` ([#1324](https://github.com/pinterest/ktlint/issues/1324)) 
+* Prevent false negative on `else` branch when body contains only chained calls or binary expression ([#2057](https://github.com/pinterest/ktlint/issues/2057))
 
 ### Changed
 

ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/MultiLineIfElseRule.kt

@@ -64,23 +64,33 @@ public class MultiLineIfElseRule :
  return
  }
 
- if (node.elementType == ELSE && node.firstChildNode?.elementType == BINARY_EXPRESSION) {
+ if (node.elementType == ELSE &&
+ node.firstChildNode?.elementType == BINARY_EXPRESSION &&
+ node.firstChildNode.firstChildNode?.elementType == IF
+ ) {
  // Allow
- // val foo = if (bar1) {
- // "bar1"
- // } else {
- // null
- // } ?: "something-else"
+ // val foo2 = if (bar1) {
+ // "bar1"
+ // } else if (bar2) {
+ // null
+ // } else {
+ // null
+ // } ?: "something-else"
  return
  }
 
- if (node.elementType == ELSE && node.firstChildNode?.elementType == DOT_QUALIFIED_EXPRESSION) {
+ if (node.elementType == ELSE &&
+ node.firstChildNode?.elementType == DOT_QUALIFIED_EXPRESSION &&
+ node.firstChildNode.firstChildNode?.elementType == IF
+ ) {
  // Allow
- // val foo = if (bar1) {
- // "bar1"
- // } else {
- // "bar2"
- // }.plus("foo")
+ // val foo = if (bar1) {
+ // "bar1"
+ // } else if (bar2) {
+ // "bar2"
+ // } else {
+ // "bar3"
+ // }.plus("foo")
  return
  }
 

ktlint-ruleset-standard/src/test/kotlin/com/pinterest/ktlint/ruleset/standard/rules/MultiLineIfElseRuleTest.kt

@@ -574,8 +574,16 @@ class MultiLineIfElseRuleTest {
  fun `Issue 1904 - Given an nested if else statement followed by an elvis operator`() {
  val code =
  """
- val foo = if (bar1) {
+ val foo1 = if (bar1) {
+ "bar1"
+ } else {
+ null
+ } ?: "something-else"
+
+ val foo2 = if (bar1) {
  "bar1"
+ } else if (bar2) {
+ null
  } else {
  null
  } ?: "something-else"
@@ -584,11 +592,39 @@ class MultiLineIfElseRuleTest {
  }
 
  @Test
- fun `Issue 1904 - Given an nested if else statement and else which is part of a dot qualified expression`() {
+ fun `Issue 2057 - Given an else condition with single line binary expression`() {
  val code =
  """
  val foo = if (bar1) {
  "bar1"
+ } else bar2 ?: "something-else"
+ """.trimIndent()
+ val formattedCode =
+ """
+ val foo = if (bar1) {
+ "bar1"
+ } else {
+ bar2 ?: "something-else"
+ }
+ """.trimIndent()
+ multiLineIfElseRuleAssertThat(code)
+ .hasLintViolations(
+ LintViolation(3, 8, "Missing { ... }"),
+ ).isFormattedAs(formattedCode)
+ }
+
+ @Test
+ fun `Issue 1904 - Given an nested if else statement and else which is part of a dot qualified expression`() {
+ val code =
+ """
+ val foo1 = if (bar1) {
+ "bar1"
+ } else {
+ "bar2"
+ }.plus("foo")
+
+ val foo2 = if (bar1) {
+ "bar1"
  } else if (bar2) {
  "bar2"
  } else {
@@ -597,4 +633,49 @@ class MultiLineIfElseRuleTest {
  """.trimIndent()
  multiLineIfElseRuleAssertThat(code).hasNoLintViolations()
  }
+
+ @Test
+ fun `Issue 2057 - Given an else with chained condition`() {
+ val code =
+ """
+ val foo = if (System.currentTimeMillis() % 2 == 0L) {
+ 0
+ } else System.currentTimeMillis().toInt()
+ """.trimIndent()
+ val formattedCode =
+ """
+ val foo = if (System.currentTimeMillis() % 2 == 0L) {
+ 0
+ } else {
+ System.currentTimeMillis().toInt()
+ }
+ """.trimIndent()
+ multiLineIfElseRuleAssertThat(code)
+ .hasLintViolations(
+ LintViolation(3, 8, "Missing { ... }"),
+ ).isFormattedAs(formattedCode)
+ }
+
+ @Test
+ fun `Issue 2057 - Given an if with chained condition`() {
+ val code =
+ """
+ val foo = if (System.currentTimeMillis() % 2 == 0L) System.currentTimeMillis().toInt()
+ else {
+ System.currentTimeMillis().toInt()
+ }
+ """.trimIndent()
+ val formattedCode =
+ """
+ val foo = if (System.currentTimeMillis() % 2 == 0L) {
+ System.currentTimeMillis().toInt()
+ } else {
+ System.currentTimeMillis().toInt()
+ }
+ """.trimIndent()
+ multiLineIfElseRuleAssertThat(code)
+ .hasLintViolations(
+ LintViolation(1, 53, "Missing { ... }"),
+ ).isFormattedAs(formattedCode)
+ }
 }