[c#] refactor local summary creator into its own util (#5236)

joern-cli/frontends/csharpsrc2cpg/src/main/scala/io/joern/csharpsrc2cpg/CSharpSrc2Cpg.scala

@@ -5,7 +5,7 @@ import io.joern.csharpsrc2cpg.astcreation.AstCreator
 import io.joern.csharpsrc2cpg.datastructures.CSharpProgramSummary
 import io.joern.csharpsrc2cpg.parser.DotNetJsonParser
 import io.joern.csharpsrc2cpg.passes.{AstCreationPass, DependencyPass}
-import io.joern.csharpsrc2cpg.utils.{DependencyDownloader, DotNetAstGenRunner}
+import io.joern.csharpsrc2cpg.utils.{DependencyDownloader, DotNetAstGenRunner, ProgramSummaryCreator}
 import io.joern.x2cpg.X2Cpg.withNewEmptyCpg
 import io.joern.x2cpg.astgen.AstGenRunner.AstGenRunnerResult
 import io.joern.x2cpg.astgen.ParserResult
@@ -35,13 +35,7 @@ class CSharpSrc2Cpg extends X2CpgFrontend[Config] {
       File.usingTemporaryDirectory("csharpsrc2cpgOut") { tmpDir =>
         val astGenResult = new DotNetAstGenRunner(config).execute(tmpDir)
         val astCreators  = CSharpSrc2Cpg.processAstGenRunnerResults(astGenResult.parsedFiles, config)
-        // Pre-parse the AST creators for high level structures
-        val internalProgramSummary = summarizeAstCreators(astCreators)
-        // Load built-in and/or external summaries for missing imports
-        val builtinSummary            = createBuiltinSummary(config, internalProgramSummary)
-        val internalAndBuiltinSummary = internalProgramSummary ++= builtinSummary
-        val externalSummary           = createExternalSummary(config, internalAndBuiltinSummary)
-        val localSummary              = internalAndBuiltinSummary ++= externalSummary
+        val localSummary = ProgramSummaryCreator.from(astCreators, config)
 
         val hash = HashUtil.sha256(astCreators.map(_.parserResult).map(x => Paths.get(x.fullPath)))
         new MetaDataPass(cpg, Languages.CSHARPSRC, config.inputPath, Option(hash)).createAndApply()
@@ -61,33 +55,6 @@ class CSharpSrc2Cpg extends X2CpgFrontend[Config] {
     }
   }
 
-  private def summarizeAstCreators(astCreators: Seq[AstCreator]): CSharpProgramSummary = {
-    ConcurrentTaskUtil
-      .runUsingThreadPool(astCreators.map(x => () => x.summarize()).iterator)
-      .flatMap {
-        case Failure(exception) =>
-          logger.warn(s"Unable to pre-parse C# file, skipping - ", exception)
-          None
-        case Success(summary) => Option(summary)
-      }
-      .foldLeft(CSharpProgramSummary(imports = CSharpProgramSummary.initialImports))(_ ++= _)
-  }
-
-  private def createBuiltinSummary(config: Config, internalSummary: CSharpProgramSummary): CSharpProgramSummary = {
-    Option
-      .when(config.useBuiltinSummaries)(CSharpProgramSummary.builtinTypesSummary)
-      .map(_.filter(namespacePred = (ns, _) => internalSummary.imports.contains(ns)))
-      .getOrElse(CSharpProgramSummary())
-  }
-
-  private def createExternalSummary(config: Config, internalSummary: CSharpProgramSummary): CSharpProgramSummary = {
-    val jsonFilePaths = config.externalSummaryPaths
-    Option
-      .when(jsonFilePaths.nonEmpty)(CSharpProgramSummary.externalTypesSummary(jsonFilePaths))
-      .map(_.filter(namespacePred = (ns, _) => internalSummary.imports.contains(ns)))
-      .getOrElse(CSharpProgramSummary())
-  }
-
   private def buildFiles(config: Config): List[String] = {
     SourceFiles.determine(
       config.inputPath,

joern-cli/frontends/csharpsrc2cpg/src/main/scala/io/joern/csharpsrc2cpg/utils/ProgramSummaryCreator.scala

@@ -0,0 +1,43 @@
+package io.joern.csharpsrc2cpg.utils
+
+import io.joern.csharpsrc2cpg.Config
+import io.joern.csharpsrc2cpg.astcreation.AstCreator
+import io.joern.csharpsrc2cpg.datastructures.CSharpProgramSummary
+import io.joern.x2cpg.utils.ConcurrentTaskUtil
+import org.slf4j.LoggerFactory
+
+import scala.util.{Failure, Success}
+
+/** Builds a `CSharpProgramSummary` by pre-parsing AST creators for high level structures, taking into account related
+  * frontend options.
+  */
+object ProgramSummaryCreator {
+
+  private val logger = LoggerFactory.getLogger(getClass)
+
+  def from(astCreators: Seq[AstCreator], config: Config): CSharpProgramSummary = {
+    val internalSummary = summarizeAstCreators(astCreators)
+    val externalSummary = buildExternalSummary(config.useBuiltinSummaries, config.externalSummaryPaths)
+    internalSummary ++= externalSummary.filter(namespacePred = (ns, _) => internalSummary.imports.contains(ns))
+  }
+
+  private def summarizeAstCreators(astCreators: Seq[AstCreator]): CSharpProgramSummary = {
+    ConcurrentTaskUtil
+      .runUsingThreadPool(astCreators.map(x => () => x.summarize()).iterator)
+      .flatMap {
+        case Failure(exception) =>
+          logger.warn(s"Unable to pre-parse C# file, skipping - ", exception)
+          None
+        case Success(summary) => Option(summary)
+      }
+      .foldLeft(CSharpProgramSummary(imports = CSharpProgramSummary.initialImports))(_ ++= _)
+  }
+
+  private def buildExternalSummary(withBuiltinTypes: Boolean, withJsonFiles: Set[String]): CSharpProgramSummary = {
+    val builtin = if withBuiltinTypes then CSharpProgramSummary.builtinTypesSummary else CSharpProgramSummary()
+    val fromJson =
+      if withJsonFiles.nonEmpty then CSharpProgramSummary.externalTypesSummary(withJsonFiles)
+      else CSharpProgramSummary()
+    builtin ++= fromJson
+  }
+}