Merge commit '13310fdad' into main

Author: alexarchambault

backend/src/main/scala/sbt/internal/inc/bloop/internal/BloopNameHashing.scala

@@ -1,5 +1,7 @@
 package sbt.internal.inc.bloop.internal
 
+import scala.collection.parallel.immutable.ParVector
+
 import _root_.bloop.UniqueCompileInputs
 import _root_.bloop.tracing.BraveTracer
 import monix.eval.Task
@@ -178,9 +180,16 @@ private final class BloopNameHashing(
           }
         }
       }
+      val removedProducts =
+        lookup.removedProducts(previousAnalysis).getOrElse {
+          new ParVector(previous.allProducts.toVector)
+            .filter(p => {
+              !equivS.equiv(previous.product(p), stamps.product(p))
+            })
+            .toVector
+            .toSet
+        }
 
-      // Unnecessary to compute removed products because we can ensure read-only classes dir is untouched
-      val removedProducts = Set.empty[VirtualFileRef]
       val changedBinaries: Set[VirtualFileRef] = tracer.traceVerbose("changed binaries") { _ =>
         lookup.changedBinaries(previousAnalysis).getOrElse {
           val detectChange = IncrementalCommon.isLibraryModified(

frontend/src/test/scala/bloop/BaseCompileSpec.scala

@@ -463,7 +463,7 @@ abstract class BaseCompileSpec extends bloop.testing.BaseSuite {
             |  public void entrypoint(String[] args) {
             |    A$ a = A$.MODULE$;
             |    System.out.println(a.HelloWorld());
-            |  }  
+            |  }
             |}""".stripMargin
         val `C.scala` =
           """/C.scala
@@ -1829,4 +1829,50 @@ abstract class BaseCompileSpec extends bloop.testing.BaseSuite {
       assertExitStatus(compiledState, ExitStatus.Ok)
     }
   }
+
+  test("detects removed products") {
+    TestUtil.withinWorkspace { workspace =>
+      object Sources {
+        val `A.scala` =
+          """/a/A.scala
+            |package a
+            |class A
+          """.stripMargin
+
+        val `B.scala` =
+          """/a/B.scala
+            |package a
+            |class B extends A
+          """.stripMargin
+
+        val `B2.scala` =
+          """/a/B.scala
+            |package a
+            |class B extends A {
+            |  def foo: Int = ???
+            |}
+          """.stripMargin
+      }
+      val logger = new RecordingLogger(ansiCodesSupported = false)
+      val `A` = TestProject(workspace, "a", List(Sources.`A.scala`, Sources.`B.scala`))
+
+      val projects = List(`A`)
+      val state = loadState(workspace, projects, logger)
+
+      val firstState = state.compile(`A`)
+      assertExitStatus(firstState, ExitStatus.Ok)
+
+      writeFile(`A`.srcFor("a/B.scala"), Sources.`B2.scala`)
+      def deleteAProduct(classesDir: AbsolutePath): Unit = {
+        val productA = classesDir.resolve("a").resolve("A.class")
+        Files.delete(productA.underlying)
+      }
+
+      deleteAProduct(firstState.getLastClassesDir(`A`).get)
+
+      val secondState = firstState.compile(`A`)
+      assertExitStatus(secondState, ExitStatus.Ok)
+
+    }
+  }
 }