Add --ignoreConfig and dont allow specifying files on commandline without it if there is config file present (#62477)

src/testRunner/tests.ts

@@ -119,6 +119,7 @@ export * from "./unittests/tsc/composite.js";
 export * from "./unittests/tsc/declarationEmit.js";
 export * from "./unittests/tsc/extends.js";
 export * from "./unittests/tsc/forceConsistentCasingInFileNames.js";
+export * from "./unittests/tsc/ignoreConfig.js";
 export * from "./unittests/tsc/incremental.js";
 export * from "./unittests/tsc/libraryResolution.js";
 export * from "./unittests/tsc/listFilesOnly.js";

src/testRunner/unittests/tsc/ignoreConfig.ts

@@ -0,0 +1,58 @@
+import * as ts from "../../_namespaces/ts.js";
+import { jsonToReadableText } from "../helpers.js";
+import { verifyTsc } from "../helpers/tsc.js";
+import { TestServerHost } from "../helpers/virtualFileSystemWithWatch.js";
+
+describe("unittests:: tsc:: ignoreConfig::", () => {
+    function sysWithoutConfig() {
+        return TestServerHost.createWatchedSystem({
+            "/home/src/workspaces/project/src/a.ts": "export const a = 10;",
+            "/home/src/workspaces/project/src/b.ts": "export const b = 10;",
+            "/home/src/workspaces/project/c.ts": "export const c = 10;",
+        });
+    }
+    function sysWithConfig() {
+        const sys = sysWithoutConfig();
+        sys.writeFile(
+            "/home/src/workspaces/project/tsconfig.json",
+            jsonToReadableText({
+                include: ["src"],
+            }),
+        );
+        return sys;
+    }
+    function runScenario(subScenario: string, commandLineArgs: readonly string[]) {
+        verifyTsc({
+            scenario: "ignoreConfig",
+            subScenario,
+            sys: sysWithConfig,
+            commandLineArgs,
+        });
+
+        verifyTsc({
+            scenario: "ignoreConfig",
+            subScenario: subScenario + " with --ignoreConfig",
+            sys: sysWithConfig,
+            commandLineArgs: commandLineArgs.concat("--ignoreConfig"),
+        });
+
+        verifyTsc({
+            scenario: "ignoreConfig",
+            subScenario: subScenario + " when config file absent",
+            sys: sysWithoutConfig,
+            commandLineArgs,
+        });
+
+        verifyTsc({
+            scenario: "ignoreConfig",
+            subScenario: subScenario + " when config file absent with --ignoreConfig",
+            sys: sysWithoutConfig,
+            commandLineArgs: commandLineArgs.concat("--ignoreConfig"),
+        });
+    }
+
+    runScenario("without any options", ts.emptyArray);
+    runScenario("specifying files", ["src/a.ts"]);
+    runScenario("specifying project", ["-p", "."]);
+    runScenario("mixing project and files", ["-p", ".", "src/a.ts", "c.ts"]);
+});

src/testRunner/unittests/tscWatch/resolutionCache.ts

@@ -424,7 +424,7 @@ declare module "fs" {
                 ],
             });
         }
-        verifyIgnore("watch without configFile", ["--w", `/user/username/projects/myproject/test.ts`]);
+        verifyIgnore("watch without configFile", ["--w", "--ignoreConfig", `/user/username/projects/myproject/test.ts`]);
         verifyIgnore("watch with configFile", ["--w", "-p", `/user/username/projects/myproject/tsconfig.json`]);
     });