fix for 3725, with tests to verify this fix, passing in WSL

Author: philwalk

modules/build/src/main/scala/scala/build/preprocessing/SheBang.scala

@@ -3,7 +3,7 @@ package scala.build.preprocessing
 import scala.util.matching.Regex
 
 object SheBang {
-  private val sheBangRegex: Regex = s"""(^(#!.*(\\X)?)+(\\X*!#.*)?)""".r
+  private val sheBangRegex: Regex = s"""(^(#!.*(\\X)?)+(\\X*^!#.*)?)""".r
 
   def isShebangScript(content: String): Boolean = sheBangRegex.unanchored.matches(content)
 

modules/build/src/test/scala/scala/build/tests/SourcesTests.scala

@@ -325,7 +325,14 @@ class SourcesTests extends TestUtil.ScalaCliBuildSuite {
           |VAL=1
           |!#
           |
-          |println("Hello World #!")""".stripMargin
+          |println("Hello World #!")""".stripMargin,
+      os.rel / "hasBangHashInComment.sc" ->
+        """#!/usr/bin/scala-cli
+          |
+          |
+          |
+          |
+          |println("Hello World !#")""".stripMargin
     )
     val expectedParsedCodes = Seq(
       """
@@ -349,7 +356,14 @@ class SourcesTests extends TestUtil.ScalaCliBuildSuite {
         |
         |
         |
-        |println("Hello World #!")""".stripMargin
+        |println("Hello World #!")""".stripMargin,
+      """
+        |
+        |
+        |
+        |
+        |
+        |println("Hello World !#")""".stripMargin
     )
 
     testInputs.withInputs { (root, inputs) =>

modules/build/src/test/scala/scala/build/tests/markdown/MarkdownCodeBlockTests.scala

@@ -69,6 +69,28 @@ class MarkdownCodeBlockTests extends TestUtil.ScalaCliBuildSuite {
     expect(actualResult == expectedResult)
   }
 
+  test("shebang closing line allowed in scala code") {
+    val code     = """println("Hello !#")""".stripMargin
+    val markdown =
+      s"""# Some snippet
+         |
+         |```scala
+         |#!/usr/bin/env -S scala-cli shebang
+         |$code
+         |```
+         |""".stripMargin
+    val expectedResult =
+      MarkdownCodeBlock(
+        info = PlainScalaInfo,
+        body = "\n" + code,
+        startLine = 3,
+        endLine = 4
+      )
+    val Right(Seq(actualResult: MarkdownCodeBlock)) =
+      MarkdownCodeBlock.findCodeBlocks(os.sub / "Example.md", markdown)
+    expect(actualResult == expectedResult)
+  }
+
   test("a raw Scala code block is extracted correctly from markdown") {
     val code = """object Main extends App {
                  |  println("Hello")