test: package.json eol is removed

.prettierignore

@@ -0,0 +1 @@
+test/fixtures

package.json

@@ -43,7 +43,7 @@
     "ofetch": "^1.3.4",
     "open": "^10.1.0",
     "pathe": "^1.1.2",
-    "pkg-types": "^1.0.3",
+    "pkg-types": "^1.1.3",
     "scule": "^1.3.0",
     "semver": "^7.6.0",
     "std-env": "^3.7.0",
@@ -63,4 +63,4 @@
     "vitest": "^1.4.0"
   },
   "packageManager": "[email protected]"
-}
+}

test/fixtures/package.json

@@ -0,0 +1,3 @@
+{
+  "//": "This file must have an empty ending line"
+}

test/package.test.ts

@@ -0,0 +1,43 @@
+import { promises as fsp } from "node:fs";
+import { describe, expect, test } from "vitest";
+import { readPackageJSON, writePackageJSON } from "../src/package";
+
+describe("package", () => {
+  const config = {
+    cwd: "./test/fixtures",
+    types: {},
+    scopeMap: {},
+    tokens: {},
+    from: "",
+    to: "",
+    output: "",
+    publish: {},
+    templates: {},
+    excludeAuthors: [],
+  };
+
+  test("read package.json with trailing newlines", async () => {
+    const file = await readPackageJSON(config);
+
+    expect(file).toMatchInlineSnapshot(`
+      {
+        "//": "This file must have an empty ending line",
+      }
+    `);
+  });
+
+  test("write package.json with trailing newlines", async () => {
+    const file = await readPackageJSON(config);
+
+    await writePackageJSON(config, file);
+
+    const newFile = await fsp.readFile("./test/fixtures/package.json", "utf8");
+
+    expect(newFile).toMatchInlineSnapshot(`
+      "{
+        "//": "This file must have an empty ending line"
+      }
+      "
+    `);
+  });
+});

vitest.config.ts

@@ -1,9 +1,14 @@
-import { defineConfig } from 'vitest/config'
+import { defineConfig } from "vitest/config";
 
 export default defineConfig({
+  server: {
+    watch: {
+      ignored: ["**/test/fixtures/package.json"],
+    },
+  },
   test: {
     coverage: {
-      reporter: ['text', 'clover', 'json']
-    }
-  }
-})
+      reporter: ["text", "clover", "json"],
+    },
+  },
+});