From ae66fce69116b5c18450fe2bed0ebad0fca6f3ce Mon Sep 17 00:00:00 2001
From: Nick Price <n.m.price@gmail.com>
Date: Tue, 7 Jun 2022 21:36:16 +0100
Subject: [PATCH] Config to control if a space is added after Constructor
 Annotation

Fixes #3260, allowing users to opt-out from the change made by #1516 for #618
---
 docs/configuration.md                         | 12 ++++++++++
 .../scala/org/scalafmt/config/Spaces.scala    |  6 ++++-
 .../scala/org/scalafmt/internal/Router.scala  |  3 ++-
 .../spaces/AfterConstructorAnnotation.stat    | 24 +++++++++++++++++++
 4 files changed, 43 insertions(+), 2 deletions(-)
 create mode 100644 scalafmt-tests/src/test/resources/spaces/AfterConstructorAnnotation.stat

diff --git a/docs/configuration.md b/docs/configuration.md
index 4231b682e2..048830555b 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -4035,6 +4035,18 @@ spaces.afterSymbolicDefs=true
 def +++(a: A): F[A]
 ```
 
+### `spaces.afterConstructorAnnotation`
+
+```scala mdoc:defaults
+spaces.afterConstructorAnnotation
+```
+
+```scala mdoc:scalafmt
+spaces.afterConstructorAnnotation=true
+---
+class A @Inject() (param1: B)
+```
+
 ## Literals
 
 > Since v2.5.0.
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/config/Spaces.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/config/Spaces.scala
index 77af28af2a..08efed6dff 100644
--- a/scalafmt-core/shared/src/main/scala/org/scalafmt/config/Spaces.scala
+++ b/scalafmt-core/shared/src/main/scala/org/scalafmt/config/Spaces.scala
@@ -43,6 +43,9 @@ import metaconfig._
   * @param afterSymbolicDefs
   *   If true, adds a single space after an operator method. For example:
   *   {{{def <=> [T](that: T): Boolean}}}
+  * @param afterConstructorAnnotation
+  *   If true, adds a single space after a constructor annotation. For example:
+  *   {{{class MyClass @Inject() (param1: SomeType)}}}
   */
 case class Spaces(
     beforeContextBoundColon: Spaces.BeforeContextBound =
@@ -54,7 +57,8 @@ case class Spaces(
     neverAroundInfixTypes: Seq[String] = Nil,
     afterKeywordBeforeParen: Boolean = true,
     inByNameTypes: Boolean = true,
-    afterSymbolicDefs: Boolean = false
+    afterSymbolicDefs: Boolean = false,
+    afterConstructorAnnotation: Boolean = true
 ) {
   def isSpaceAfterKeyword(tokenAfter: Token): Boolean =
     afterKeywordBeforeParen || !tokenAfter.is[Token.LeftParen]
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
index de8c0b3601..298fe00d94 100644
--- a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
+++ b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
@@ -674,7 +674,8 @@ class Router(formatOps: FormatOps) {
           // see:
           // https://github.com/scalameta/scalafmt/pull/1516
           // https://github.com/scalameta/scalafmt/issues/1528
-          case init: Init if init.parent.forall(_.is[Mod.Annot]) => Space
+          case init: Init if init.parent.forall(_.is[Mod.Annot]) =>
+            Space(style.spaces.afterConstructorAnnotation)
           case t: Term.Name
               if style.spaces.afterTripleEquals && t.value == "===" =>
             Space
diff --git a/scalafmt-tests/src/test/resources/spaces/AfterConstructorAnnotation.stat b/scalafmt-tests/src/test/resources/spaces/AfterConstructorAnnotation.stat
new file mode 100644
index 0000000000..f998283786
--- /dev/null
+++ b/scalafmt-tests/src/test/resources/spaces/AfterConstructorAnnotation.stat
@@ -0,0 +1,24 @@
+spaces.afterConstructorAnnotation = true
+<<< Space between annotation and ctor argument list
+class A @Inject()(b: C)
+>>>
+class A @Inject() (b: C)
+
+<<< Space between annotation and ctor argument list (with multiple argument list)
+class MyComponent @Inject()(ctx: Context)(ws: WSClient)
+>>>
+class MyComponent @Inject() (ctx: Context)(ws: WSClient)
+
+<<< No space between annotation and ctor argument list
+spaces.afterConstructorAnnotation = false
+===
+class A @Inject() (b: C)
+>>>
+class A @Inject()(b: C)
+
+<<< No space between annotation and ctor argument list (with multiple argument list)
+spaces.afterConstructorAnnotation = false
+===
+class MyComponent @Inject() (ctx: Context)(ws: WSClient)
+>>>
+class MyComponent @Inject()(ctx: Context)(ws: WSClient)