Restrict Scala CLI detection to .sc and .scala files (#2971)

Author: fthomas

modules/core/src/main/scala/org/scalasteward/core/buildtool/scalacli/ScalaCliAlg.scala

@@ -41,9 +41,10 @@ final class ScalaCliAlg[F[_]](implicit
 
   override def containsBuild(buildRoot: BuildRoot): F[Boolean] = {
     val buildRootPath = buildRoot.relativePath.dropWhile(Set('.', '/'))
+    val extensions = Set(".sc", ".scala")
     gitAlg
       .findFilesContaining(buildRoot.repo, "//> using lib ")
-      .map(_.exists(_.startsWith(buildRootPath)))
+      .map(_.exists(path => path.startsWith(buildRootPath) && extensions.exists(path.endsWith)))
   }
 
   override def getDependencies(buildRoot: BuildRoot): F[List[Scope.Dependencies]] =

modules/core/src/test/scala/org/scalasteward/core/buildtool/scalacli/ScalaCliAlgTest.scala

@@ -5,12 +5,25 @@ import org.scalasteward.core.buildtool.BuildRoot
 import org.scalasteward.core.buildtool.sbt.command._
 import org.scalasteward.core.data.{GroupId, Repo, Version}
 import org.scalasteward.core.edit.scalafix.ScalafixMigration
+import org.scalasteward.core.git.FileGitAlg
 import org.scalasteward.core.mock.MockContext.context._
 import org.scalasteward.core.mock.MockState
 import org.scalasteward.core.mock.MockState.TraceEntry.{Cmd, Log}
 import org.scalasteward.core.util.Nel
 
 class ScalaCliAlgTest extends CatsEffectSuite {
+  test("containsBuild: directive in non-source file") {
+    val repo = Repo("user", "repo")
+    val buildRoot = BuildRoot(repo, ".")
+    val fileWithUsingLib = "test.md" // this test fails if the extension is .scala or .sc
+    val grepCmd = FileGitAlg.gitCmd.toList ++
+      List("grep", "-I", "--fixed-strings", "--files-with-matches", "//> using lib ")
+    val initial =
+      MockState.empty.copy(commandOutputs = Map(grepCmd -> Right(List(fileWithUsingLib))))
+    val obtained = scalaCliAlg.containsBuild(buildRoot).runA(initial)
+    assertIO(obtained, false)
+  }
+
   test("getDependencies") {
     val repo = Repo("user", "repo")
     val buildRoot = BuildRoot(repo, ".")