Scalafmt: don't parse shebang line as scala

scalameta · Oct 3, 2023 · d8ffb3f · d8ffb3f
1 parent 5641152
commit d8ffb3f
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Showing 4 changed files with 24 additions and 21 deletions.
diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/Scalafmt.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/Scalafmt.scala
@@ -79,19 +79,33 @@ object Scalafmt {
     )
   }
 
+  private[scalafmt] def splitCodePrefix(input: String): (String, String) =
+    if (!input.startsWith("#!")) ("", input)
+    else {
+      val beforeNL = input.indexOf(UnixLineEnding, 2)
+      if (beforeNL < 0) (input + UnixLineEnding, "")
+      else {
+        val afterNL = beforeNL + UnixLineEnding.length
+        val hasBlank = input.startsWith(UnixLineEnding, afterNL)
+        val idx = if (hasBlank) afterNL + UnixLineEnding.length else afterNL
+        (input.substring(0, idx), input.substring(idx))
+      }
+    }
+
   private def formatCodeWithStyle(
       code: String,
       style: ScalafmtConfig,
       range: Set[Range],
       filename: String
   ): Formatted.Result = {
     val isWin = code.contains(WinLineEnding)
-    val unixCode =
+    val (prefix, unixCode) = splitCodePrefix(
       if (isWin) code.replaceAll(WinLineEnding, UnixLineEnding) else code
+    )
     doFormat(unixCode, style, filename, range) match {
       case Failure(e) => Formatted.Result(Formatted.Failure(e), style)
       case Success(x) =>
-        val s = if (x.isEmpty) UnixLineEnding else x
+        val s = if (prefix.isEmpty && x.isEmpty) UnixLineEnding else prefix + x
         val asWin = style.lineEndings == LineEndings.windows ||
           (isWin && style.lineEndings == LineEndings.preserve)
         val res = if (asWin) s.replaceAll(UnixLineEnding, WinLineEnding) else s

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
@@ -68,21 +68,9 @@ class Router(formatOps: FormatOps) {
       case FormatToken(_: T.EOF, _, _) => Seq(Split(Newline, 0))
       case ft @ FormatToken(_, _: T.BOF, _) =>
         Seq(Split(NoSplit.orNL(next(ft).right.is[T.EOF]), 0))
-      case FormatToken(_: T.BOF, right, _) =>
-        val policy = right match {
-          case T.Ident(name) if name.startsWith("#!") =>
-            val nl = findFirst(next(formatToken), Int.MaxValue) { x =>
-              x.hasBreak || x.right.is[T.EOF]
-            }
-            nl.fold(Policy.noPolicy) { ft =>
-              Policy.on(ft.left) { case Decision(t, _) =>
-                Seq(Split(Space(t.between.nonEmpty), 0))
-              }
-            }
-          case _ => Policy.NoPolicy
-        }
+      case FormatToken(_: T.BOF, _, _) =>
         Seq(
-          Split(NoSplit, 0).withPolicy(policy)
+          Split(NoSplit, 0)
         )
       case FormatToken(_, _: T.EOF, _) =>
         Seq(

diff --git a/scalafmt-tests/src/test/resources/test/Dialect.source b/scalafmt-tests/src/test/resources/test/Dialect.source
@@ -40,7 +40,7 @@ addSbtPlugin( "io.get-coursier" % "sbt-coursier" %  "1.0.0-M14")
 addSbtPlugin( "com.eed3si9n" % "sbt-assembly" %  "0.14.3")
 addSbtPlugin( "org.brianmckenna" % "sbt-wartremover" % "0.14")
 >>> foo.sc
-#!/usr/bin/env amm
+#!/usr/bin/env   amm
 
 addSbtPlugin("io.get-coursier"  % "sbt-coursier"    % "1.0.0-M14")
 addSbtPlugin("com.eed3si9n"     % "sbt-assembly"    % "0.14.3")
@@ -51,7 +51,7 @@ rewrite.rules = [AvoidInfix]
 ===
 #!/usr/bin/env   amm
 >>> foo.sc
-#!/usr/bin/env amm
+#!/usr/bin/env   amm
 <<< #2104
 runner.dialect = scala3
 ===
@@ -232,6 +232,6 @@ foo(
 def main(args: Array[String]): Unit =
    println("hello")
 >>>
-test does not parse
 #!/usr/bin/env -S scala @classpathAtfile
-                        ^
+def main(args: Array[String]): Unit =
+  println("hello")
diff --git a/scalafmt-tests/src/test/scala/org/scalafmt/util/FormatAssertions.scala b/scalafmt-tests/src/test/scala/org/scalafmt/util/FormatAssertions.scala
@@ -32,7 +32,8 @@ trait FormatAssertions {
       obtained: String
   )(implicit ev: Parse[T], dialect: Dialect): Unit = {
     import scala.meta._
-    def toInput(code: String) = Scalafmt.toInput(code, filename)
+    def toInput(code: String) =
+      Scalafmt.toInput(Scalafmt.splitCodePrefix(code)._2, filename)
     toInput(original).parse[T] match {
       case Parsed.Error(pos, message, _) =>
         val msgWithPos = pos.formatMessage("error", message)