Merge pull request #2329 from github/henrymercer/csharp-buildless-rollback-mechanism

Add rollback mechanism for C# buildless

Author: henrymercer

Diff for: lib/config-utils.js

@@ -1086,44 +1086,56 @@ const mockRepositoryNwo = parseRepositoryNwo("owner/repo");
   });
 });
 
-test("Build mode not overridden when disable Java buildless feature flag disabled", async (t) => {
-  const messages: LoggedMessage[] = [];
-  const buildMode = await configUtils.parseBuildModeInput(
-    "none",
-    [Language.java],
-    createFeatures([]),
-    getRecordingLogger(messages),
-  );
-  t.is(buildMode, BuildMode.None);
-  t.deepEqual(messages, []);
-});
+for (const { displayName, language, feature } of [
+  {
+    displayName: "Java",
+    language: Language.java,
+    feature: Feature.DisableJavaBuildlessEnabled,
+  },
+  {
+    displayName: "C#",
+    language: Language.csharp,
+    feature: Feature.DisableCsharpBuildless,
+  },
+]) {
+  test(`Build mode not overridden when disable ${displayName} buildless feature flag disabled`, async (t) => {
+    const messages: LoggedMessage[] = [];
+    const buildMode = await configUtils.parseBuildModeInput(
+      "none",
+      [language],
+      createFeatures([]),
+      getRecordingLogger(messages),
+    );
+    t.is(buildMode, BuildMode.None);
+    t.deepEqual(messages, []);
+  });
 
-test("Build mode not overridden for other languages", async (t) => {
-  const messages: LoggedMessage[] = [];
-  const buildMode = await configUtils.parseBuildModeInput(
-    "none",
-    [Language.python],
-    createFeatures([Feature.DisableJavaBuildlessEnabled]),
-    getRecordingLogger(messages),
-  );
-  t.is(buildMode, BuildMode.None);
-  t.deepEqual(messages, []);
-});
+  test(`Build mode not overridden for other languages when disable ${displayName} buildless feature flag enabled`, async (t) => {
+    const messages: LoggedMessage[] = [];
+    const buildMode = await configUtils.parseBuildModeInput(
+      "none",
+      [Language.python],
+      createFeatures([feature]),
+      getRecordingLogger(messages),
+    );
+    t.is(buildMode, BuildMode.None);
+    t.deepEqual(messages, []);
+  });
 
-test("Build mode overridden when analyzing Java and disable Java buildless feature flag enabled", async (t) => {
-  const messages: LoggedMessage[] = [];
-  const buildMode = await configUtils.parseBuildModeInput(
-    "none",
-    [Language.java],
-    createFeatures([Feature.DisableJavaBuildlessEnabled]),
-    getRecordingLogger(messages),
-  );
-  t.is(buildMode, BuildMode.Autobuild);
-  t.deepEqual(messages, [
-    {
-      message:
-        "Scanning Java code without a build is temporarily unavailable. Falling back to 'autobuild' build mode.",
-      type: "warning",
-    },
-  ]);
-});
+  test(`Build mode overridden when analyzing ${displayName} and disable ${displayName} buildless feature flag enabled`, async (t) => {
+    const messages: LoggedMessage[] = [];
+    const buildMode = await configUtils.parseBuildModeInput(
+      "none",
+      [language],
+      createFeatures([feature]),
+      getRecordingLogger(messages),
+    );
+    t.is(buildMode, BuildMode.Autobuild);
+    t.deepEqual(messages, [
+      {
+        message: `Scanning ${displayName} code without a build is temporarily unavailable. Falling back to 'autobuild' build mode.`,
+        type: "warning",
+      },
+    ]);
+  });
+}

Diff for: lib/config-utils.js.map

@@ -1108,6 +1108,16 @@ export async function parseBuildModeInput(
     );
   }
 
+  if (
+    languages.includes(Language.csharp) &&
+    (await features.getValue(Feature.DisableCsharpBuildless))
+  ) {
+    logger.warning(
+      "Scanning C# code without a build is temporarily unavailable. Falling back to 'autobuild' build mode.",
+    );
+    return BuildMode.Autobuild;
+  }
+
   if (
     languages.includes(Language.java) &&
     (await features.getValue(Feature.DisableJavaBuildlessEnabled))

Diff for: lib/config-utils.test.js

@@ -49,6 +49,7 @@ export enum Feature {
   CleanupTrapCaches = "cleanup_trap_caches",
   CppDependencyInstallation = "cpp_dependency_installation_enabled",
   CppTrapCachingEnabled = "cpp_trap_caching_enabled",
+  DisableCsharpBuildless = "disable_csharp_buildless",
   DisableJavaBuildlessEnabled = "disable_java_buildless_enabled",
   DisableKotlinAnalysisEnabled = "disable_kotlin_analysis_enabled",
   ExportDiagnosticsEnabled = "export_diagnostics_enabled",
@@ -109,6 +110,11 @@ export const featureConfig: Record<
     legacyApi: true,
     minimumVersion: "2.16.1",
   },
+  [Feature.DisableCsharpBuildless]: {
+    defaultValue: false,
+    envVar: "CODEQL_ACTION_DISABLE_CSHARP_BUILDLESS",
+    minimumVersion: undefined,
+  },
   [Feature.DisableJavaBuildlessEnabled]: {
     defaultValue: false,
     envVar: "CODEQL_ACTION_DISABLE_JAVA_BUILDLESS",