Improve detection of a changed project

Author: Denis Mikhaylov

src/main/scala/com/elarib/PartialSbtPlugin.scala

@@ -2,9 +2,9 @@ package com.elarib
 
 import com.elarib.model.{ChangeGetter, PartialSbParser}
 import org.apache.logging.log4j.LogManager
-import sbt.Keys._
+import sbt.*
+import sbt.Keys.*
 import sbt.internal.BuildDependencies.DependencyMap
-import sbt._
 
 object BuildKeys {
   val partialSbtExcludedFiles = sbt.settingKey[Seq[sbt.File]]("Files that should be excluded from analysis.")
@@ -112,10 +112,17 @@ object PartialSbtPlugin extends AutoPlugin {
 
         val diffsFiles: Seq[sbt.File] = changeGetter.changes.filterNot(f => isFileExcluded(baseDir)(f, excludedFiles))
 
-        val modulesToBuild: Seq[ResolvedProject] = modulesWithPath
-          .filter { case (_, resolvedProject) =>
-            diffsFiles.exists(file => file.getAbsolutePath.contains(resolvedProject.base.getAbsolutePath))
-          }
+        def findContainingProject(file: File): Option[(ProjectRef, ResolvedProject)] =
+          modulesWithPath
+            .filter { case (_, resolvedProject) =>
+              file.getAbsolutePath.contains(resolvedProject.base.getAbsolutePath)
+            }
+            .sortBy(_._2.base.getAbsolutePath.length)
+            .lastOption
+
+        diffsFiles
+          .flatMap(findContainingProject)
+          .distinct
           .flatMap { case (projectRef, resolvedProject) =>
             reverseDependencyMap
               .get(projectRef)
@@ -124,8 +131,6 @@ object PartialSbtPlugin extends AutoPlugin {
           }
           .distinct
           .sortBy(_.id)
-
-        modulesToBuild
     }
 
   }
@@ -162,5 +167,4 @@ object PartialSbtPlugin extends AutoPlugin {
         else
           file.getCanonicalPath == ef.getCanonicalPath
     }
-
 }

src/sbt-test/test-projects/multi-module-project/build.sbt

@@ -83,6 +83,10 @@ lazy val secondLib = sbt
   .settings(com.elarib.BuildKeys.partialSbtOpaqueProject := ())
 
 //Tools
+lazy val toolsProject = sbt
+  .Project("tools", tools)
+  .settings(settings("tools"))
+
 lazy val firstTool = sbt
   .Project("tool-1", tools / "tool-1")
   .dependsOn(firstLib)

src/sbt-test/test-projects/multi-module-project/expected/5.log

@@ -1,5 +1,5 @@
-Metabuild files have changed. Need to reload all the 10 projects
-10 projects have been changed
+Metabuild files have changed. Need to reload all the 11 projects
+11 projects have been changed
 lib-1
 lib-2
 multi-module-project
@@ -9,4 +9,5 @@ service-3
 service-4
 tool-1
 tool-2
-tool-3
+tool-3
+tools