fix: ensure Terraform is available for integration tests

.github/workflows/ci.yaml

@@ -16,14 +16,23 @@ jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: coder/coder/.github/actions/setup-tf@main
-      - uses: oven-sh/setup-bun@v2
+      - name: Check out code
+        uses: actions/checkout@v4
+      - name: Set up Terraform
+        uses: coder/coder/.github/actions/setup-tf@main
+      - name: Set up Bun
+        uses: oven-sh/setup-bun@v2
         with:
+          # We're using the latest version of Bun for now, but it might be worth
+          # reconsidering. They've pushed breaking changes in patch releases
+          # that have broken our CI.
+          # Our PR where issues started to pop up: https://github.com/coder/modules/pull/383
+          # The Bun PR that broke things: https://github.com/oven-sh/bun/pull/16067
           bun-version: latest
-      - name: Setup
+      - name: Install dependencies
         run: bun install
-      - run: bun test
+      - name: Run tests
+        run: bun test
   pretty:
     runs-on: ubuntu-latest
     steps:

setup.ts

@@ -25,7 +25,7 @@ const removeOldContainers = async () => {
     "-a",
     "-q",
     "--filter",
-    `label=modules-test`,
+    "label=modules-test",
   ]);
   let containerIDsRaw = await readableStreamToText(proc.stdout);
   let exitCode = await proc.exited;

test.ts

@@ -194,13 +194,18 @@ export const testRequiredVariables = <TVars extends TerraformVariables>(
 export const runTerraformApply = async <TVars extends TerraformVariables>(
   dir: string,
   vars: Readonly<TVars>,
-  env?: Record<string, string>,
+  customEnv?: Record<string, string>,
 ): Promise<TerraformState> => {
   const stateFile = `${dir}/${crypto.randomUUID()}.tfstate`;
 
-  const combinedEnv = env === undefined ? {} : { ...env };
-  for (const [key, value] of Object.entries(vars)) {
-    combinedEnv[`TF_VAR_${key}`] = String(value);
+  const childEnv: Record<string, string | undefined> = {
+    ...process.env,
+    ...(customEnv ?? {}),
+  };
+  for (const [key, value] of Object.entries(vars) as [string, JsonValue][]) {
+    if (value !== null) {
+      childEnv[`TF_VAR_${key}`] = String(value);
+    }
   }
 
   const proc = spawn(
@@ -216,7 +221,7 @@ export const runTerraformApply = async <TVars extends TerraformVariables>(
     ],
     {
       cwd: dir,
-      env: combinedEnv,
+      env: childEnv,
       stderr: "pipe",
       stdout: "pipe",
     },