add test cases

Author: chouchouji

simple-git-hooks.test.js

@@ -361,6 +361,30 @@ describe("Simple Git Hooks tests", () => {
         expect(isEqual(installedHooks, {})).toBe(true);
       });
 
+      it("only removes git hooks which are not in preserveUnused", () => {
+        createGitHooksFolder(PROJECT_WITH_UNUSED_CONF_IN_PACKAGE_JSON);
+
+        const installedHooksDir = path.normalize(
+            path.join(PROJECT_WITH_UNUSED_CONF_IN_PACKAGE_JSON, ".git", "hooks")
+        );
+
+        fs.writeFileSync(
+            path.resolve(installedHooksDir, "commit-msg"),
+            "# do nothing"
+        );
+
+        let installedHooks = getInstalledGitHooks(installedHooksDir);
+
+        expect(isEqual(installedHooks, { "commit-msg": "# do nothing" })).toBe(true);
+
+        simpleGitHooks.setHooksFromConfig(PROJECT_WITH_UNUSED_CONF_IN_PACKAGE_JSON);
+
+        simpleGitHooks.removeHooks(PROJECT_WITH_UNUSED_CONF_IN_PACKAGE_JSON);
+
+        installedHooks = getInstalledGitHooks(installedHooksDir);
+        expect(isEqual(installedHooks, { "commit-msg": "# do nothing" })).toBe(true);
+      });
+
       it("creates git hooks and removes unused git hooks", () => {
         createGitHooksFolder(PROJECT_WITH_CONF_IN_PACKAGE_JSON);