Add environment variable override

src/init.ts

@@ -1,18 +1,22 @@
 import * as fs from "fs";
 import * as path from "path";
 
+import * as core from "@actions/core";
 import * as toolrunner from "@actions/exec/lib/toolrunner";
+import * as github from "@actions/github";
 import * as io from "@actions/io";
 import * as yaml from "js-yaml";
 
 import {
   getOptionalInput,
   isAnalyzingPullRequest,
+  isDefaultSetup,
   isSelfHostedRunner,
 } from "./actions-util";
 import { GitHubApiDetails } from "./api-client";
 import { CodeQL, setupCodeQL } from "./codeql";
 import * as configUtils from "./config-utils";
+import { EnvVar } from "./environment";
 import {
   CodeQLDefaultVersionInfo,
   Feature,
@@ -329,6 +333,18 @@ export async function getFileCoverageInformationEnabled(
       showDeprecationWarning: false,
     };
   }
+  // If the user has explicitly opted out via an environment variable, don't
+  // show the deprecation warning.
+  if (
+    (process.env[EnvVar.FILE_COVERAGE_ON_PRS] || "").toLocaleLowerCase() ===
+    "true"
+  ) {
+    return {
+      enabled: true,
+      enabledByRepositoryProperty: false,
+      showDeprecationWarning: false,
+    };
+  }
   // Allow repositories to opt in to file coverage information on PRs
   // using a repository property. In this case, don't show the deprecation
   // warning since the repository has explicitly opted in.
@@ -358,3 +374,45 @@ export async function getFileCoverageInformationEnabled(
     showDeprecationWarning: false,
   };
 }
+
+/**
+ * Log a warning about the deprecation of file coverage information on PRs, including how to opt
+ * back in via an environment variable or repository property.
+ */
+export function logFileCoverageOnPrsDeprecationWarning(logger: Logger): void {
+  if (process.env[EnvVar.DID_LOG_FILE_COVERAGE_ON_PRS_DEPRECATION]) {
+    return;
+  }
+
+  const repositoryOwnerType: string | undefined =
+    github.context.payload.repository?.owner.type;
+
+  let message =
+    "Starting April 2026, the CodeQL Action will skip computing file coverage information on pull requests " +
+    "to improve analysis performance. File coverage information will still be computed on non-PR analyses.";
+  const envVarOptOut =
+    "set the `CODEQL_ACTION_FILE_COVERAGE_ON_PRS` environment variable to `true`.";
+  const repoPropertyOptOut =
+    "create a custom repository property with the name " +
+    '`github-codeql-file-coverage-on-prs` and the type "True/false", then set this property to ' +
+    "`true` in the repository's settings.";
+
+  if (repositoryOwnerType === "Organization") {
+    // Org-owned repo: can use the repository property
+    if (isDefaultSetup()) {
+      message += `\n\nTo opt out of this change, ${repoPropertyOptOut}`;
+    } else {
+      message += `\n\nTo opt out of this change, ${envVarOptOut} Alternatively, ${repoPropertyOptOut}`;
+    }
+  } else if (isDefaultSetup()) {
+    // User-owned repo on default setup: no repo property available and
+    // no way to set env vars, so need to switch to advanced setup.
+    message += `\n\nTo opt out of this change, switch to an advanced setup workflow and ${envVarOptOut}`;
+  } else {
+    // User-owned repo on advanced setup: can set the env var
+    message += `\n\nTo opt out of this change, ${envVarOptOut}`;
+  }
+
+  logger.warning(message);
+  core.exportVariable(EnvVar.DID_LOG_FILE_COVERAGE_ON_PRS_DEPRECATION, "true");
+}