From 91a577a8e097acb48e5c1a51c72b488c40738e9c Mon Sep 17 00:00:00 2001
From: Albert Meltzer <7529386+kitbellew@users.noreply.github.com>
Date: Sun, 28 Nov 2021 23:47:02 -0800
Subject: [PATCH] FileOps: move getFileMatcher from dynamic runner

---
 .../scalafmt/cli/ScalafmtDynamicRunner.scala  | 19 +---------------
 .../scala/org/scalafmt/sysops/FileOps.scala   | 22 +++++++++++++++++++
 2 files changed, 23 insertions(+), 18 deletions(-)

diff --git a/scalafmt-cli/src/main/scala/org/scalafmt/cli/ScalafmtDynamicRunner.scala b/scalafmt-cli/src/main/scala/org/scalafmt/cli/ScalafmtDynamicRunner.scala
index 1c438c0c39..0e5bf17fc8 100644
--- a/scalafmt-cli/src/main/scala/org/scalafmt/cli/ScalafmtDynamicRunner.scala
+++ b/scalafmt-cli/src/main/scala/org/scalafmt/cli/ScalafmtDynamicRunner.scala
@@ -1,6 +1,5 @@
 package org.scalafmt.cli
 
-import java.io.File
 import java.nio.file.Path
 import java.util.concurrent.atomic.{AtomicInteger, AtomicReference}
 
@@ -36,7 +35,7 @@ object ScalafmtDynamicRunner extends ScalafmtRunner {
     val sessionMatcher = session.matchesProjectFilters _
     val filterMatcher: Path => Boolean =
       options.customFilesOpt.fold(sessionMatcher) { customFiles =>
-        val customMatcher = getFileMatcher(customFiles.map(_.path))
+        val customMatcher = FileOps.getFileMatcher(customFiles.map(_.path))
         x => customMatcher(x) && sessionMatcher(x)
       }
     val inputMethods = getInputMethods(options, filterMatcher)
@@ -81,20 +80,4 @@ object ScalafmtDynamicRunner extends ScalafmtRunner {
     inputMethod.write(formatResult, input, options)
   }
 
-  private def getFileMatcher(paths: Seq[Path]): Path => Boolean = {
-    require(paths.nonEmpty)
-    val (files, dirs) = paths.partition(FileOps.isRegularFile)
-    (x: Path) =>
-      files.contains(x) || {
-        val filename = x.toString()
-        dirs.exists { dir =>
-          val dirname = dir.toString()
-          filename.startsWith(dirname) && (
-            filename.length == dirname.length ||
-              filename.charAt(dirname.length) == File.separatorChar
-          )
-        }
-      }
-  }
-
 }
diff --git a/scalafmt-sysops/shared/src/main/scala/org/scalafmt/sysops/FileOps.scala b/scalafmt-sysops/shared/src/main/scala/org/scalafmt/sysops/FileOps.scala
index 73d72c5e9e..6719a83f6e 100644
--- a/scalafmt-sysops/shared/src/main/scala/org/scalafmt/sysops/FileOps.scala
+++ b/scalafmt-sysops/shared/src/main/scala/org/scalafmt/sysops/FileOps.scala
@@ -118,4 +118,26 @@ object FileOps {
     else if (file.isRegularFile) Some(Success(file.path))
     else Some(Failure(new AccessDeniedException(s"Config not a file: $file")))
 
+  def getFileMatcher(paths: Seq[Path]): Path => Boolean = {
+    val dirBuilder = Seq.newBuilder[Path]
+    val fileBuilder = Set.newBuilder[Path]
+    paths.foreach { path =>
+      if (isRegularFile(path)) fileBuilder += path else dirBuilder += path
+    }
+    val dirs = dirBuilder.result()
+    val files = fileBuilder.result()
+    x =>
+      files(x) || {
+        val filename = x.toString()
+        val sep = x.getFileSystem.getSeparator
+        dirs.exists { dir =>
+          val dirname = dir.toString()
+          filename.startsWith(dirname) && {
+            filename.length == dirname.length ||
+            filename.startsWith(sep, dirname.length)
+          }
+        }
+      }
+  }
+
 }