Fix false positive with value argument list has lambda (indent) (#1176

)

CHANGELOG.md

@@ -11,6 +11,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - Fix false positive with eol comment (`annotation-spacing`) ([#1124](https://github.com/pinterest/ktlint/issues/1124))
 - Fix KtLint dependency variant selection ([#1114](https://github.com/pinterest/ktlint/issues/1114))
 - Fix false positive with 'by lazy {}' (`indent`) ([#1162](https://github.com/pinterest/ktlint/issues/1162))
+- Fix false positive with value argument list has lambda (`indent`) ([#764](https://github.com/pinterest/ktlint/issues/764))
 ### Changed
 - Updated to dokka 1.4.32 ([#1148](https://github.com/pinterest/ktlint/pull/1148))
 - Updated Kotlin to 1.5.20 version

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

@@ -84,6 +84,7 @@ import java.util.LinkedList
 import org.jetbrains.kotlin.com.intellij.lang.ASTNode
 import org.jetbrains.kotlin.com.intellij.psi.PsiComment
 import org.jetbrains.kotlin.com.intellij.psi.impl.source.tree.LeafPsiElement
+import org.jetbrains.kotlin.com.intellij.psi.tree.IElementType
 import org.jetbrains.kotlin.com.intellij.psi.tree.TokenSet
 import org.jetbrains.kotlin.psi.KtStringTemplateExpression
 import org.jetbrains.kotlin.psi.KtSuperTypeList
@@ -189,9 +190,11 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
         var firstArg: ASTNode? = null
         // matching ), ] or }
         val r = node.nextSibling {
-            newlineInBetween = newlineInBetween || it.textContains('\n')
+            val isValueArgument = it.elementType == VALUE_ARGUMENT
+            val hasLineBreak = if (isValueArgument) it.hasLineBreak(LAMBDA_EXPRESSION, FUN) else it.hasLineBreak()
+            newlineInBetween = newlineInBetween || hasLineBreak
             parameterListInBetween = parameterListInBetween || it.elementType == VALUE_PARAMETER_LIST
-            if (it.elementType == VALUE_ARGUMENT) {
+            if (isValueArgument) {
                 numberOfArgs++
                 firstArg = it
             }
@@ -291,10 +294,12 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
         emit: (offset: Int, errorMessage: String, canBeAutoCorrected: Boolean) -> Unit
     ) {
         for (c in node.children()) {
-            if (
-                (c.elementType == VALUE_PARAMETER || c.elementType == VALUE_ARGUMENT || c.elementType == ANNOTATION) &&
-                c.textContains('\n')
-            ) {
+            val hasLineBreak = when (c.elementType) {
+                VALUE_ARGUMENT -> c.hasLineBreak(LAMBDA_EXPRESSION, FUN)
+                VALUE_PARAMETER, ANNOTATION -> c.hasLineBreak()
+                else -> false
+            }
+            if (hasLineBreak) {
                 // rearrange
                 //
                 // a, b, value(
@@ -460,7 +465,8 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
                     LPAR, LBRACE, LBRACKET -> {
                         // ({[ should increase expectedIndent by 1
                         val prevBlockLine = ctx.blockOpeningLineStack.peek() ?: -1
-                        if (prevBlockLine != line) {
+                        val leftBrace = n.takeIf { it.elementType == LBRACE }
+                        if (prevBlockLine != line && !leftBrace.isAfterLambdaArgumentOnSameLine()) {
                             expectedIndent++
                             debug { "++${n.text} -> $expectedIndent" }
                         }
@@ -470,12 +476,10 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
                         // ]}) should decrease expectedIndent by 1
                         val blockLine = ctx.blockOpeningLineStack.pop()
                         val prevBlockLine = ctx.blockOpeningLineStack.peek() ?: -1
-                        if (prevBlockLine != blockLine) {
+                        val pairedLeftBrace = n.pairedLeftBrace()
+                        if (prevBlockLine != blockLine && !pairedLeftBrace.isAfterLambdaArgumentOnSameLine()) {
                             expectedIndent--
-                            val byKeywordOnSameLine = n.pairedLeftBrace()
-                                ?.leaves(forward = false)
-                                ?.takeWhile { !it.isWhiteSpaceWithNewline() }
-                                ?.firstOrNull { it.elementType == BY_KEYWORD }
+                            val byKeywordOnSameLine = pairedLeftBrace?.prevLeafOnSameLine(BY_KEYWORD)
                             if (byKeywordOnSameLine != null &&
                                 byKeywordOnSameLine.prevLeaf()?.isWhiteSpaceWithNewline() == true &&
                                 !byKeywordOnSameLine.isPartOf(DELEGATED_SUPER_TYPE_ENTRY)
@@ -1111,4 +1115,24 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
         }
         return null
     }
+
+    private fun ASTNode.prevLeafOnSameLine(prevLeafType: IElementType): ASTNode? {
+        return leaves(forward = false)
+            .takeWhile { !it.isWhiteSpaceWithNewline() }
+            .firstOrNull { it.elementType == prevLeafType }
+    }
+
+    private fun ASTNode?.isAfterLambdaArgumentOnSameLine(): Boolean {
+        return this?.prevLeafOnSameLine(RBRACE)?.nextCodeLeaf()?.treeParent?.elementType == VALUE_ARGUMENT_LIST
+    }
+
+    private fun ASTNode.hasLineBreak(vararg ignoreElementTypes: IElementType): Boolean {
+        if (isWhiteSpaceWithNewline()) return true
+        return if (ignoreElementTypes.isEmpty()) {
+            textContains('\n')
+        } else {
+            elementType !in ignoreElementTypes &&
+                children().any { c -> c.textContains('\n') && c.elementType !in ignoreElementTypes }
+        }
+    }
 }

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

@@ -914,4 +914,65 @@ internal class IndentationRuleTest {
             )
         ).isEmpty()
     }
+
+    // https://github.com/pinterest/ktlint/issues/764
+    @Test
+    fun `lint value argument list with lambda`() {
+        assertThat(
+            IndentationRule().lint(
+                """
+                fun test(i: Int, f: (Int) -> Unit) {
+                    f(i)
+                }
+
+                fun main() {
+                    test(1, f = {
+                        println(it)
+                    })
+                }
+                """.trimIndent()
+            )
+        ).isEmpty()
+    }
+
+    @Test
+    fun `lint value argument list with two lambdas`() {
+        assertThat(
+            IndentationRule().lint(
+                """
+                fun test(f: () -> Unit, g: () -> Unit) {
+                    f()
+                    g()
+                }
+
+                fun main() {
+                    test({
+                        println(1)
+                    }, {
+                        println(2)
+                    })
+                }
+                """.trimIndent()
+            )
+        ).isEmpty()
+    }
+
+    @Test
+    fun `lint value argument list with anonymous function`() {
+        assertThat(
+            IndentationRule().lint(
+                """
+                fun test(i: Int, f: (Int) -> Unit) {
+                    f(i)
+                }
+
+                fun main() {
+                    test(1, fun(it: Int) {
+                        println(it)
+                    })
+                }
+                """.trimIndent()
+            )
+        ).isEmpty()
+    }
 }

ktlint-ruleset-standard/src/test/resources/spec/indent/format-argument-list-expected.kt.spec

@@ -1,11 +1,7 @@
 fun main() {
-    f(
-        a, b,
-        {
-            // body
-        },
-        c, d
-    )
+    f(a, b, {
+        // body
+    }, c, d)
 
     fn(
         a,