Update readme with config needed to run tests locally (#1056)

* Update readme with config needed to run tests locally

* Remove coma from README.md

* FIx typos in README.md

* Refactor driver./test/testUtil.ts

README.md

@@ -231,6 +231,14 @@ $ yarn workspaces run build      # build all packages
 $ yarn workspaces run test       # run tests for all packages
 ```
 
+> In order to be able to run all tests you need to have `edgedb-server` in your
+> path. This can be done by either running tests from within a Python 3.12
+> virtual environment (you will have it if you built EdgeDB locally), or by
+> [installing](https://docs.edgedb.com/cli/edgedb_server/edgedb_server_install#ref-cli-edgedb-server-install)
+> specific EdgeDB version and then adding its binary path to the `EDGEDB_SERVER_BIN` environment variable.
+> Check [here](https://docs.edgedb.com/cli/edgedb_server/edgedb_server_info#ref-cli-edgedb-server-info)
+> to find how to get the binary path.
+
 ## License
 
 `edgedb-js` is developed and distributed under the Apache 2.0 license.

packages/driver/test/testUtil.ts

@@ -147,8 +147,16 @@ export const startServer = async (
   if (process.env.EDGEDB_DEBUG_SERVER) {
     console.log(`running command: ${cmd.join(" ")}`);
   }
+
+  const maybeEnvWithDevMode =
+    process.env.EDGEDB_SERVER_BIN || process.env.CI
+      ? {}
+      : {
+          __EDGEDB_DEVMODE: "1",
+        };
+
   const proc = child_process.spawn(cmd[0], cmd.slice(1), {
-    env: { ...process.env, ...env },
+    env: { ...process.env, ...env, ...maybeEnvWithDevMode },
   });
 
   try {