From 130a955d53e62016ea0c98ec34caa2c1941ae5f1 Mon Sep 17 00:00:00 2001
From: Piotr Chabelski <ged.subfan@gmail.com>
Date: Fri, 4 Oct 2024 16:06:06 +0200
Subject: [PATCH] Ensure resource directories passed via a `using` directive
 aren't ignored in `--watch` mode

---
 .../src/main/scala/scala/build/Build.scala    | 19 +++++++++++--
 .../RunWithWatchTestDefinitions.scala         | 28 +++++++++++++++++++
 2 files changed, 44 insertions(+), 3 deletions(-)

diff --git a/modules/build/src/main/scala/scala/build/Build.scala b/modules/build/src/main/scala/scala/build/Build.scala
index d22552c71c..73fe4a2fe5 100644
--- a/modules/build/src/main/scala/scala/build/Build.scala
+++ b/modules/build/src/main/scala/scala/build/Build.scala
@@ -687,10 +687,23 @@ object Build {
       either {
         val (crossSources: CrossSources, inputs0: Inputs) =
           value(allInputs(inputs, options, logger))
+        val resourceDirectoriesFromDirectives = {
+          // resource directories passed via a command line option are registered as Input elements.
+          // however, those passed via a using directive are only passed via build options.
+          // TODO: refactor and clean this up
+          val resourceDirsFromCli =
+            inputs0.elements.flatMap { case rd: ResourceDirectory => Some(rd.path); case _ => None }
+          val latestResourceDirsFromBuildOptions: Seq[os.Path] =
+            crossSources.buildOptions.flatMap(_.value.classPathOptions.resourcesDir).distinct
+          latestResourceDirsFromBuildOptions
+            .filter(!resourceDirsFromCli.contains(_))
+            .map(ResourceDirectory(_))
+        }
+        val finalInputs   = inputs0.add(resourceDirectoriesFromDirectives)
         val sharedOptions = crossSources.sharedOptions(options)
         val compiler: ScalaCompiler = value {
           compilerMaker.create(
-            inputs0.workspace / Constants.workspaceDirName,
+            finalInputs.workspace / Constants.workspaceDirName,
             classesDir0,
             buildClient,
             logger,
@@ -698,13 +711,13 @@ object Build {
           )
         }
         val docCompilerOpt: Option[ScalaCompiler] = docCompilerMakerOpt.map(_.create(
-          inputs0.workspace / Constants.workspaceDirName,
+          finalInputs.workspace / Constants.workspaceDirName,
           classesDir0,
           buildClient,
           logger,
           sharedOptions
         )).map(value)
-        (compiler, docCompilerOpt, crossSources, inputs0)
+        (compiler, docCompilerOpt, crossSources, finalInputs)
       }
 
     var res: Either[BuildException, Builds] = null
diff --git a/modules/integration/src/test/scala/scala/cli/integration/RunWithWatchTestDefinitions.scala b/modules/integration/src/test/scala/scala/cli/integration/RunWithWatchTestDefinitions.scala
index a298d03849..c740aa1a69 100644
--- a/modules/integration/src/test/scala/scala/cli/integration/RunWithWatchTestDefinitions.scala
+++ b/modules/integration/src/test/scala/scala/cli/integration/RunWithWatchTestDefinitions.scala
@@ -308,4 +308,32 @@ trait RunWithWatchTestDefinitions { _: RunTestDefinitions =>
         }
       }
     }
+
+  for {
+    useDirective <- Seq(false, true)
+    directive       = if (useDirective) "//> using resourceDirs ./resources" else ""
+    resourceOptions = if (useDirective) Nil else Seq("--resource-dirs", "./src/proj/resources")
+    title           = if (useDirective) "directive" else "command line"
+  } test(s"resources via $title with --watch") {
+    val expectedMessage1 = "Hello"
+    val expectedMessage2 = "world"
+    resourcesInputs(directive = directive, resourceContent = expectedMessage1)
+      .fromRoot { root =>
+        TestUtil.withProcessWatching(
+          os.proc(TestUtil.cli, "run", "src", "--watch", resourceOptions, extraOptions)
+            .spawn(cwd = root, stderr = os.Pipe)
+        ) { (proc, timeout, ec) =>
+          val output1 = TestUtil.readLine(proc.stdout, ec, timeout)
+          expect(output1 == expectedMessage1)
+          proc.printStderrUntilRerun(timeout)(ec)
+          val Some((resourcePath, newResourceContent)) =
+            resourcesInputs(directive = directive, resourceContent = expectedMessage2)
+              .files
+              .find(_._1.toString.contains("resources"))
+          os.write.over(root / resourcePath, newResourceContent)
+          val output2 = TestUtil.readLine(proc.stdout, ec, timeout)
+          expect(output2 == expectedMessage2)
+        }
+      }
+  }
 }