[Test] Reuse runResolution and runCheckers from analyze.kt

compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/pipeline/analyse.kt

@@ -5,7 +5,8 @@
 
 package org.jetbrains.kotlin.fir.pipeline
 
-import org.jetbrains.kotlin.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.diagnostics.KtDiagnostic
+import org.jetbrains.kotlin.diagnostics.impl.BaseDiagnosticsCollector
 import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.analysis.collectors.FirDiagnosticsCollector
 import org.jetbrains.kotlin.fir.declarations.FirFile
@@ -19,7 +20,11 @@ fun FirSession.runResolution(firFiles: List<FirFile>): Pair<ScopeSession, List<F
     return resolveProcessor.scopeSession to firFiles
 }
 
-fun FirSession.runCheckers(scopeSession: ScopeSession, firFiles: List<FirFile>, reporter: DiagnosticReporter) {
+fun FirSession.runCheckers(
+    scopeSession: ScopeSession,
+    firFiles: List<FirFile>,
+    reporter: BaseDiagnosticsCollector
+): Map<FirFile, List<KtDiagnostic>> {
     val collector = FirDiagnosticsCollector.create(this, scopeSession)
     collector.collectDiagnosticsInSettings(reporter)
     for (file in firFiles) {
@@ -27,4 +32,8 @@ fun FirSession.runCheckers(scopeSession: ScopeSession, firFiles: List<FirFile>,
             collector.collectDiagnostics(file, reporter)
         }
     }
+    return firFiles.associateWith {
+        val path = it.sourceFile?.path ?: return@associateWith emptyList()
+        reporter.diagnosticsByFilePath[path] ?: emptyList()
+    }
 }

compiler/fir/entrypoint/src/org/jetbrains/kotlin/fir/pipeline/firUtils.kt

@@ -66,7 +66,7 @@ fun buildResolveAndCheckFirFromKtFiles(
 fun resolveAndCheckFir(
     session: FirSession,
     firFiles: List<FirFile>,
-    diagnosticsReporter: DiagnosticReporter
+    diagnosticsReporter: BaseDiagnosticsCollector
 ): ModuleCompilerAnalyzedOutput {
     val (scopeSession, fir) = session.runResolution(firFiles)
     session.runCheckers(scopeSession, fir, diagnosticsReporter)
@@ -76,7 +76,7 @@ fun resolveAndCheckFir(
 fun buildResolveAndCheckFirViaLightTree(
     session: FirSession,
     ktFiles: Collection<KtSourceFile>,
-    diagnosticsReporter: DiagnosticReporter,
+    diagnosticsReporter: BaseDiagnosticsCollector,
     countFilesAndLines: KFunction2<Int, Int, Unit>?
 ): ModuleCompilerAnalyzedOutput {
     val firFiles = session.buildFirViaLightTree(ktFiles, diagnosticsReporter, countFilesAndLines)