Print recompilation reasons in build report

compiler/incremental-compilation-impl/src/org/jetbrains/kotlin/incremental/DirtyFilesContainer.kt

@@ -18,10 +18,13 @@ class DirtyFilesContainer(
     fun toMutableList(): MutableList<File> =
         ArrayList(myDirtyFiles)
 
-    fun add(files: Iterable<File>) {
+    fun add(files: Iterable<File>, reason: String?) {
         val existingKotlinFiles = files.filter { it.isKotlinFile(sourceFilesExtensions) }
         if (existingKotlinFiles.isNotEmpty()) {
             myDirtyFiles.addAll(existingKotlinFiles)
+            if (reason != null) {
+                reporter.reportMarkDirty(existingKotlinFiles, reason)
+            }
         }
     }
 
@@ -29,7 +32,8 @@ class DirtyFilesContainer(
         if (lookupSymbols.isEmpty()) return
 
         val dirtyFilesFromLookups = mapLookupSymbolsToFiles(caches.lookupCache, lookupSymbols, reporter)
-        add(dirtyFilesFromLookups)
+        // reason is null, because files are reported in mapLookupSymbolsToFiles
+        add(dirtyFilesFromLookups, reason = null)
     }
 
     fun addByDirtyClasses(dirtyClassesFqNames: Collection<FqName>) {
@@ -43,6 +47,7 @@ class DirtyFilesContainer(
         }
         val dirtyFilesFromFqNames =
             mapClassesFqNamesToFiles(listOf(caches.platformCache), fqNamesWithSubtypes, reporter)
-        add(dirtyFilesFromFqNames)
+        // reason is null, because files are reported in mapClassesFqNamesToFiles
+        add(dirtyFilesFromFqNames, reason = null)
     }
 }

compiler/incremental-compilation-impl/src/org/jetbrains/kotlin/incremental/IncrementalCompilerRunner.kt

@@ -139,16 +139,16 @@ abstract class IncrementalCompilerRunner<
     protected abstract fun calculateSourcesToCompile(caches: CacheManager, changedFiles: ChangedFiles.Known, args: Args): CompilationMode
 
     protected fun initDirtyFiles(dirtyFiles: DirtyFilesContainer, changedFiles: ChangedFiles.Known) {
-        dirtyFiles.add(changedFiles.modified)
-        dirtyFiles.add(changedFiles.removed)
+        dirtyFiles.add(changedFiles.modified, "was modified since last time")
+        dirtyFiles.add(changedFiles.removed, "was removed since last time")
 
         if (dirtySourcesSinceLastTimeFile.exists()) {
             val files = dirtySourcesSinceLastTimeFile.readLines().map(::File)
             if (files.isNotEmpty()) {
-                reporter.report { "Source files added since last compilation: ${reporter.pathsAsString(files)}" }
+                reporter.reportVerbose { "Source files added since last compilation: ${reporter.pathsAsString(files)}" }
             }
 
-            dirtyFiles.add(files)
+            dirtyFiles.add(files, "was not compiled last time")
         }
     }