Do not install core deps on self-hosted runners

Author: Sam Eagen

src/install.ts

@@ -24,9 +24,12 @@ export async function install(platform: string, architecture: string, release: s
         return Promise.reject(Error(`Release '${releaseInfo.name}' is not supported. Use 'R2020b' or a later release.`));
     }
 
-    await core.group("Preparing system for MATLAB", async () =>
-        matlab.installSystemDependencies(platform, architecture, releaseInfo.name)
-    );
+    // Install system dependencies if cloud-hosted
+    if (process.env["RUNNER_ENVIRONMENT"] === "github-hosted" && process.env["AGENT_ISSELFHOSTED"] !== "1") {
+        await core.group("Preparing system for MATLAB", async () => {
+            await matlab.installSystemDependencies(platform, architecture, releaseInfo.name);
+        });
+    }
 
     await core.group("Setting up MATLAB", async () => {
         let matlabArch = architecture;

src/install.unit.test.ts

@@ -26,6 +26,9 @@ describe("install procedure", () => {
     let setOutputMock: jest.Mock;
     let restoreMATLABMock: jest.Mock;
 
+    const runnerEnv = "github-hosted";
+    const agentIsSelfHosted = "0";
+
     const platform = "linux";
     const arch = "x64";
     const release = "latest";
@@ -57,6 +60,9 @@ describe("install procedure", () => {
         });
         matlabGetReleaseInfoMock.mockResolvedValue(releaseInfo);
         matlabGetToolcacheDirMock.mockResolvedValue(["/opt/hostedtoolcache/MATLAB/9.13.0/x64", false]);
+
+        process.env["RUNNER_ENVIRONMENT"] = runnerEnv;
+        process.env["AGENT_ISSELFHOSTED"] = agentIsSelfHosted;
     });
 
     it("ideally works", async () => {
@@ -91,6 +97,17 @@ describe("install procedure", () => {
         await expect(doInstall()).rejects.toBeDefined();
     });
 
+    it("sets up dependencies for github-hosted runners", async () => {
+        await doInstall();
+        expect(matlabInstallSystemDependenciesMock).toHaveBeenCalled();
+    });
+
+    it("does not set up dependencies for self-hosted runners", async () => {
+        process.env["RUNNER_ENVIRONMENT"] = "self-hosted";
+        await doInstall();
+        expect(matlabInstallSystemDependenciesMock).not.toHaveBeenCalled();
+    });
+
     it("rejects when the setup deps fails", async () => {
         matlabInstallSystemDependenciesMock.mockRejectedValueOnce(Error("oof"));
         await expect(doInstall()).rejects.toBeDefined();