Fix indent of "by" keyword

Original fix for pinterest#1210 solved the runtime exception during formatting but also
reformatted some delegate by constructs which are conflicting with the default
IntelliJ formatting.

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

@@ -26,6 +26,7 @@ import com.pinterest.ktlint.core.ast.ElementType.EQ
 import com.pinterest.ktlint.core.ast.ElementType.FUN
 import com.pinterest.ktlint.core.ast.ElementType.FUNCTION_LITERAL
 import com.pinterest.ktlint.core.ast.ElementType.GT
+import com.pinterest.ktlint.core.ast.ElementType.IDENTIFIER
 import com.pinterest.ktlint.core.ast.ElementType.KDOC
 import com.pinterest.ktlint.core.ast.ElementType.KDOC_END
 import com.pinterest.ktlint.core.ast.ElementType.KDOC_LEADING_ASTERISK
@@ -163,6 +164,11 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
         Companion.debug { "phase: indentation" }
         // step 2: correct indentation
         indent(node, autoCorrect, emit, editorConfig)
+
+        // The expectedIndent should never be negative. If so, it is very likely that ktlint crashes at runtime when
+        // autocorrecting is executed while no error occurs with linting only. Such errors often are not found in unit
+        // tests, as the examples are way more simple than realistic code.
+        assert(expectedIndent >= 0)
     }
 
     private fun rearrange(
@@ -742,7 +748,13 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
         val byKeywordLeaf = n
             .findChildByType(DELEGATED_SUPER_TYPE_ENTRY)
             ?.findChildByType(BY_KEYWORD)
-        if (n.prevLeaf()?.textContains('\n') == true && byKeywordLeaf?.prevLeaf().isWhiteSpaceWithNewline()) {
+        if (n.prevLeaf()?.textContains('\n') == true &&
+            byKeywordLeaf?.prevLeaf().isWhiteSpaceWithNewline()
+        ) {
+            Unit
+        } else if (byKeywordLeaf?.prevLeaf()?.textContains('\n') == true &&
+            byKeywordLeaf.prevLeaf()?.treeParent?.nextLeaf()?.elementType == IDENTIFIER
+        ) {
             Unit
         } else {
             expectedIndent--
@@ -1014,6 +1026,10 @@ class IndentationRule : Rule("indent"), Rule.Modifier.RestrictToRootLast {
                     node.treeParent.prevLeaf()?.textContains('\n') == true
                 ) {
                     0
+                } else if (node.isPartOf(DELEGATED_SUPER_TYPE_ENTRY) &&
+                    node.treeParent.nextLeaf()?.elementType == IDENTIFIER
+                ) {
+                    0
                 } else {
                     expectedIndent++
                     debug { "++whitespace followed by BY keyword -> $expectedIndent" }

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

@@ -955,39 +955,15 @@ internal class IndentationRuleTest {
     fun `lint and format delegation 2`() {
         val code =
             """
-            interface Foo
-
-            class Bar(a: Int, b: Int, c: Int) : Foo
-
             class Test2 : Foo
             by Bar(
                 a = 1,
                 b = 2,
                 c = 3
             )
             """.trimIndent()
-        val formattedCode =
-            """
-            interface Foo
-
-            class Bar(a: Int, b: Int, c: Int) : Foo
-
-            class Test2 : Foo
-                by Bar(
-                    a = 1,
-                    b = 2,
-                    c = 3
-                )
-            """.trimIndent()
-
-        assertThat(IndentationRule().lint(code)).containsExactly(
-            LintError(6, 1, "indent", "Unexpected indentation (0) (should be 4)"),
-            LintError(7, 1, "indent", "Unexpected indentation (4) (should be 8)"),
-            LintError(8, 1, "indent", "Unexpected indentation (4) (should be 8)"),
-            LintError(9, 1, "indent", "Unexpected indentation (4) (should be 8)"),
-            LintError(10, 1, "indent", "Unexpected indentation (0) (should be 4)"),
-        )
-        assertThat(IndentationRule().format(code)).isEqualTo(formattedCode)
+        assertThat(IndentationRule().format(code)).isEqualTo(code)
+        assertThat(IndentationRule().lint(code)).isEmpty()
     }
 
     @Test
@@ -1582,30 +1558,6 @@ internal class IndentationRuleTest {
             object ApplicationComponentFactory : ApplicationComponent.Factory
             by DaggerApplicationComponent.factory()
             """.trimIndent()
-        val formattedCode =
-            """
-            object ApplicationComponentFactory : ApplicationComponent.Factory
-                by DaggerApplicationComponent.factory()
-            """.trimIndent()
-        assertThat(IndentationRule().lint(code)).containsExactly(
-            LintError(2, 1, "indent", "Unexpected indentation (0) (should be 4)")
-        )
-        assertThat(IndentationRule().format(code)).isEqualTo(formattedCode)
-    }
-
-    @Test
-    fun `Issue 1210 - format of statements after supertype delegated entry 1`() {
-        val code =
-            """
-            object Issue1210 : ApplicationComponent.Factory
-                by DaggerApplicationComponent.factory()
-
-            // The next line ensures that the fix regarding the expectedIndex due to alignment of "by" keyword in
-            // class above, is still in place. Without this fix, the expectedIndex would hold a negative value,
-            // resulting in the formatting to crash on the next line.
-            val bar = 1
-            """.trimIndent()
-
         assertThat(IndentationRule().lint(code)).isEmpty()
         assertThat(IndentationRule().format(code)).isEqualTo(code)
     }