From 3575180dfe1a897e97bb8052ebd2c01cc7509484 Mon Sep 17 00:00:00 2001
From: Brice Jaglin <bjaglin@gmail.com>
Date: Thu, 9 Nov 2023 16:54:44 +0100
Subject: [PATCH] rules capturing leading tokens can be suppressed with
 scalafix:ok

---
 .../scalafix/internal/patch/EscapeHatch.scala | 40 ++++++++++++++++---
 .../disableSyntax/DisableSyntaxBase.scala     |  3 ++
 2 files changed, 37 insertions(+), 6 deletions(-)

diff --git a/scalafix-core/src/main/scala/scalafix/internal/patch/EscapeHatch.scala b/scalafix-core/src/main/scala/scalafix/internal/patch/EscapeHatch.scala
index 85429664b4..b198f7a4bc 100644
--- a/scalafix-core/src/main/scala/scalafix/internal/patch/EscapeHatch.scala
+++ b/scalafix-core/src/main/scala/scalafix/internal/patch/EscapeHatch.scala
@@ -365,7 +365,8 @@ object EscapeHatch {
         associatedComments: LazyValue[AssociatedComments]
     ): AnchoredEscapes = {
       val enable = TreeMap.newBuilder[EscapeOffset, List[EscapeFilter]]
-      val disable = TreeMap.newBuilder[EscapeOffset, List[EscapeFilter]]
+      val disableList =
+        ListBuffer.newBuilder[(EscapeOffset, List[EscapeFilter])]
       val visitedFilterExpression = mutable.Set.empty[Position]
       val onOffTracker = new OnOffTracker
 
@@ -422,9 +423,11 @@ object EscapeHatch {
             case comment @ Token.Comment(ScalafixOkRgx(rules)) =>
               if (!visitedFilterExpression.contains(comment.pos)) {
                 val rulesPos = rulesWithPosition(rules, comment)
-                val start = EscapeOffset(t.pos.start)
+                // include line start in case the rule captures leading tokens
+                val start = EscapeOffset(t.pos.start - t.pos.startColumn)
                 val end = Some(EscapeOffset(t.pos.end))
-                disable += (start -> makeFilters(rulesPos, start, end, comment))
+                disableList +=
+                  (start -> makeFilters(rulesPos, start, end, comment))
                 visitedFilterExpression += comment.pos
               }
 
@@ -444,7 +447,12 @@ object EscapeHatch {
             case ScalafixOffRgx(rules) =>
               val rulesPos = rulesWithPosition(rules, comment)
               val start = EscapeOffset(comment.pos.start)
-              disable += (start -> makeFilters(rulesPos, start, None, comment))
+              disableList += (start -> makeFilters(
+                rulesPos,
+                start,
+                None,
+                comment
+              ))
               onOffTracker.trackOff(rulesPos, comment)
 
             // matches on anchors
@@ -470,7 +478,8 @@ object EscapeHatch {
                 val start =
                   EscapeOffset(comment.pos.start - comment.pos.startColumn)
                 val end = Some(EscapeOffset(comment.pos.end))
-                disable += (start -> makeFilters(rulesPos, start, end, comment))
+                disableList +=
+                  (start -> makeFilters(rulesPos, start, end, comment))
               }
 
             case _ => ()
@@ -479,10 +488,29 @@ object EscapeHatch {
         case _ => ()
       }
 
+      val disable = TreeMap.newBuilder[EscapeOffset, List[EscapeFilter]]
+      val unused = ListBuffer.from(onOffTracker.allUnused)
+
+      // for filters starting on the same offset, pick the one with the wider range
+      // and mark the others as unused
+      disableList.result().groupBy(_._1).valuesIterator.foreach {
+        filtersForOffset =>
+          val sorted = filtersForOffset.sortBy { case (_, filters) =>
+            filters.headOption.flatMap(_.endOffset.map(-_.offset))
+          }
+
+          sorted.result() match {
+            case head :: tail =>
+              disable += head
+              unused ++= tail.flatMap(_._2).map(_.cause)
+            case _ =>
+          }
+      }
+
       new AnchoredEscapes(
         enable.result(),
         disable.result(),
-        onOffTracker.allUnused
+        unused.result()
       )
     }
   }
diff --git a/scalafix-tests/input/src/main/scala/test/disableSyntax/DisableSyntaxBase.scala b/scalafix-tests/input/src/main/scala/test/disableSyntax/DisableSyntaxBase.scala
index 873dfc1793..1c821abd65 100644
--- a/scalafix-tests/input/src/main/scala/test/disableSyntax/DisableSyntaxBase.scala
+++ b/scalafix-tests/input/src/main/scala/test/disableSyntax/DisableSyntaxBase.scala
@@ -22,6 +22,7 @@ DisableSyntax.regex = [
     message = "Numbers ({$1} in this instance) should always have a named parameter attached, or be assigned to a val."
   }
   "Await\\.result"
+  ".*bar\\s"
 ]
 */
 package test.disableSyntax
@@ -61,6 +62,8 @@ Numbers (5 in this instance) should always have a named parameter attached, or b
   // actually 7.5 million years
   Await.result(Future(fortyTwo), someDays) // assert: DisableSyntax.Await\.result
 
+  val bar = 1 // scalafix:ok
+
   override def finalize(): Unit = println("exit") // assert: DisableSyntax.noFinalize
 
   val Right(notFound) = 1.asInstanceOf[Either[String, String]]