feat: add unit tests for plugin metadata resolution (#70)

Author: subhashkhileri

.husky/pre-commit

@@ -1 +1,2 @@
 yarn lint-staged
+yarn build && yarn test

src/utils/plugin-metadata.test.ts

@@ -0,0 +1,112 @@
+/**
+ * Shared test helpers for plugin-metadata tests.
+ */
+import fs from "fs-extra";
+import path from "path";
+import os from "os";
+import yaml from "js-yaml";
+
+/** Saves and restores process.env around each test. */
+export function withCleanEnv() {
+  let savedEnv: Record<string, string | undefined>;
+  return {
+    save() {
+      savedEnv = { ...process.env };
+    },
+    restore() {
+      for (const key of Object.keys(process.env)) {
+        if (!(key in savedEnv)) delete process.env[key];
+      }
+      Object.assign(process.env, savedEnv);
+    },
+  };
+}
+
+/** Creates a temporary metadata directory with Package CRD YAML files. */
+export async function createMetadataFixture(
+  plugins: Array<{
+    name: string;
+    packageName: string;
+    dynamicArtifact: string;
+    appConfigExamples?: Record<string, unknown>;
+  }>,
+): Promise<string> {
+  const tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), "metadata-test-"));
+  for (const plugin of plugins) {
+    const content: Record<string, unknown> = {
+      apiVersion: "extensions.backstage.io/v1alpha1",
+      kind: "Package",
+      metadata: { name: plugin.name },
+      spec: {
+        packageName: plugin.packageName,
+        dynamicArtifact: plugin.dynamicArtifact,
+        ...(plugin.appConfigExamples
+          ? {
+              appConfigExamples: [
+                { title: "Default", content: plugin.appConfigExamples },
+              ],
+            }
+          : {}),
+      },
+    };
+    await fs.writeFile(
+      path.join(tmpDir, `${plugin.name}.yaml`),
+      yaml.dump(content),
+    );
+  }
+  return tmpDir;
+}
+
+/**
+ * Creates a workspace-like directory structure with metadata, source.json,
+ * and plugins-list.yaml. Used for tests that trigger PR OCI URL fetching.
+ */
+export async function createWorkspaceFixture(
+  plugins: Array<{
+    name: string;
+    packageName: string;
+    dynamicArtifact: string;
+    appConfigExamples?: Record<string, unknown>;
+  }>,
+): Promise<{ wsDir: string; metadataDir: string }> {
+  const wsDir = await fs.mkdtemp(path.join(os.tmpdir(), "workspace-test-"));
+  const metadataDir = path.join(wsDir, "metadata");
+  await fs.mkdir(metadataDir);
+
+  /* eslint-disable @typescript-eslint/naming-convention */
+  await fs.writeFile(
+    path.join(wsDir, "source.json"),
+    JSON.stringify({
+      repo: "https://github.com/test/repo",
+      "repo-ref": "main",
+      "repo-flat": false,
+    }),
+  );
+  /* eslint-enable @typescript-eslint/naming-convention */
+  await fs.writeFile(path.join(wsDir, "plugins-list.yaml"), "{}");
+
+  for (const plugin of plugins) {
+    const content: Record<string, unknown> = {
+      apiVersion: "extensions.backstage.io/v1alpha1",
+      kind: "Package",
+      metadata: { name: plugin.name },
+      spec: {
+        packageName: plugin.packageName,
+        dynamicArtifact: plugin.dynamicArtifact,
+        ...(plugin.appConfigExamples
+          ? {
+              appConfigExamples: [
+                { title: "Default", content: plugin.appConfigExamples },
+              ],
+            }
+          : {}),
+      },
+    };
+    await fs.writeFile(
+      path.join(metadataDir, `${plugin.name}.yaml`),
+      yaml.dump(content),
+    );
+  }
+
+  return { wsDir, metadataDir };
+}