test(jest-snapshot): add new case for inline snapshot behaviour

Author: G-Rath

Diff for: e2e/__tests__/__snapshots__/toMatchInlineSnapshot.test.ts.snap

@@ -118,6 +118,20 @@ test('handles property matchers', () => {
 
 `;
 
+exports[`indentation is correct in the presences of existing snapshots, when the file is correctly formatted by prettier: existing snapshot 1`] = `
+it('is true', () => {
+  expect(true).toMatchInlineSnapshot(\`true\`);
+  expect([1, 2, 3]).toMatchInlineSnapshot(\`
+    Array [
+      1,
+      2,
+      3,
+    ]
+  \`);
+});
+
+`;
+
 exports[`indentation is correct in the presences of existing snapshots: existing snapshot 1`] = `
 test('existing snapshot', () => {
   expect({hello: 'world'}).toMatchInlineSnapshot(\`

Diff for: e2e/__tests__/toMatchInlineSnapshot.test.ts

@@ -382,3 +382,20 @@ test('indentation is correct in the presences of existing snapshots', () => {
   expect(exitCode).toBe(0);
   expect(wrap(fileAfter)).toMatchSnapshot('existing snapshot');
 });
+
+test('indentation is correct in the presences of existing snapshots, when the file is correctly formatted by prettier', () => {
+  const filename = 'existing-snapshot.test.js';
+  const test = `
+    it('is true', () => {
+      expect(true).toMatchInlineSnapshot(\`true\`);
+      expect([1, 2, 3]).toMatchInlineSnapshot();
+    });\\n
+  `;
+
+  writeFiles(TESTS_DIR, {[filename]: test});
+  const {stderr, exitCode} = runJest(DIR, ['-w=1', '--ci=false', filename]);
+  const fileAfter = readFile(filename);
+  expect(stderr).toMatch('1 snapshot written from 1 test suite.');
+  expect(exitCode).toBe(0);
+  expect(wrap(fileAfter)).toMatchSnapshot('existing snapshot');
+});