Services: Misc fixes mostly related to error handling

CHANGELOG.md

@@ -8,11 +8,17 @@ Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+### Added
+
 - Added `"service": true` setting, which is well suited for long-running
   processes like servers. A service is started either when it is invoked directly,
   or when another script that depends on it is ready to run. A service is stopped
   when all scripts that depend on it have finished, or when Wireit is exited.
 
+### Fixed
+
+- Fixed memory leak in watch mode.
+
 ## [0.7.2] - 2022-09-25
 
 ### Fixed

src/cli.ts

@@ -105,6 +105,22 @@ const run = async (): Promise<Result<void, Failure[]>> => {
     if (!result.ok) {
       return result;
     }
+    const persistentServices = result.value;
+    if (persistentServices.size > 0) {
+      const failures: Failure[] = [];
+      for (const service of persistentServices.values()) {
+        const result = await service.terminated;
+        if (!result.ok) {
+          failures.push(result.error);
+        }
+      }
+      if (failures.length > 0) {
+        return {
+          ok: false,
+          error: failures,
+        };
+      }
+    }
   }
   return {ok: true, value: undefined};
 };

src/event.ts

@@ -94,6 +94,7 @@ export type Failure =
   | DependencyOnMissingScript
   | DependencyInvalid
   | ServiceExitedUnexpectedly
+  | DependencyServiceExitedUnexpectedly
   | Aborted;
 
 interface ErrorBase<T extends PackageReference = ScriptReference>
@@ -250,6 +251,14 @@ export interface ServiceExitedUnexpectedly extends ErrorBase {
   reason: 'service-exited-unexpectedly';
 }
 
+/**
+ * A service that we depend on exited before it was supposed to, causing us to
+ * fail as well.
+ */
+export interface DependencyServiceExitedUnexpectedly extends ErrorBase {
+  reason: 'dependency-service-exited-unexpectedly';
+}
+
 /**
  * A script was killed or is refusing to run because it was intentionally
  * aborted. Usually due to an error occuring in another script somewhere.

src/execution/base.ts

@@ -141,7 +141,7 @@ export abstract class BaseExecutionWithCommand<
       const errors: Failure[] = [];
       for (const result of results) {
         if (!result.ok) {
-          errors.push(...result.error);
+          errors.push(result.error);
         }
       }
       if (errors.length > 0) {