Enable sub-language file coverage behind a feature flag

CHANGELOG.md

@@ -5,6 +5,7 @@ See the [releases page](https://github.com/github/codeql-action/releases) for th
 ## [UNRELEASED]
 
 - We are rolling out a feature in October 2023 that will improve the success rate of C/C++ autobuild. [#1889](https://github.com/github/codeql-action/pull/1889)
+- We are rolling out a feature in October 2023 that will provide specific file coverage information for C and C++, Java and Kotlin, and JavaScript and TypeScript. Currently file coverage information for each of these pairs of languages is grouped together. [#1903](https://github.com/github/codeql-action/pull/1903)
 - Add a warning to help customers avoid inadvertently analyzing the same CodeQL language in multiple matrix jobs. [#1901](https://github.com/github/codeql-action/pull/1901)
 
 ## 2.21.8 - 19 Sep 2023

src/codeql.ts

@@ -20,6 +20,7 @@ import {
   Feature,
   FeatureEnablement,
   useCodeScanningConfigInCli,
+  CODEQL_VERSION_SUBLANGUAGE_FILE_COVERAGE,
 } from "./feature-flags";
 import { isTracedLanguage, Language } from "./languages";
 import { Logger } from "./logging";
@@ -611,6 +612,19 @@ export async function getCodeQLForCmd(
         extraArgs.push("--calculate-language-specific-baseline");
       }
 
+      if (
+        await features.getValue(Feature.SublanguageFileCoverageEnabled, this)
+      ) {
+        extraArgs.push("--sublanguage-file-coverage");
+      } else if (
+        await util.codeQlVersionAbove(
+          this,
+          CODEQL_VERSION_SUBLANGUAGE_FILE_COVERAGE,
+        )
+      ) {
+        extraArgs.push("--no-sublanguage-file-coverage");
+      }
+
       await runTool(
         cmd,
         [

src/feature-flags.ts

@@ -29,6 +29,11 @@ export const CODEQL_VERSION_ANALYSIS_SUMMARY_V2 = "2.14.0";
  */
 export const CODEQL_VERSION_INTRA_LAYER_PARALLELISM = "2.14.6";
 
+/**
+ * Versions 2.15.0+ of the CodeQL CLI support sub-language file coverage information.
+ */
+export const CODEQL_VERSION_SUBLANGUAGE_FILE_COVERAGE = "2.15.0";
+
 export interface CodeQLDefaultVersionInfo {
   cliVersion: string;
   tagName: string;
@@ -59,6 +64,7 @@ export enum Feature {
   ExportDiagnosticsEnabled = "export_diagnostics_enabled",
   MlPoweredQueriesEnabled = "ml_powered_queries_enabled",
   QaTelemetryEnabled = "qa_telemetry_enabled",
+  SublanguageFileCoverageEnabled = "sublanguage_file_coverage_enabled",
   UploadFailedSarifEnabled = "upload_failed_sarif_enabled",
 }
 
@@ -111,6 +117,11 @@ export const featureConfig: Record<
     minimumVersion: undefined,
     defaultValue: false,
   },
+  [Feature.SublanguageFileCoverageEnabled]: {
+    envVar: "CODEQL_ACTION_SUBLANGUAGE_FILE_COVERAGE",
+    minimumVersion: CODEQL_VERSION_SUBLANGUAGE_FILE_COVERAGE,
+    defaultValue: false,
+  },
   [Feature.UploadFailedSarifEnabled]: {
     envVar: "CODEQL_ACTION_UPLOAD_FAILED_SARIF",
     minimumVersion: "2.11.3",