Fix inline snapshot indenting

CHANGELOG.md

@@ -11,6 +11,7 @@
 - `[jest-matcher-utils]` Fix diff highlight of symbol-keyed object. ([#9499](https://github.com/facebook/jest/pull/9499))
 - `[jest-resolve]` Fix module identity preservation with symlinks and browser field resolution ([#9511](https://github.com/facebook/jest/pull/9511))
 - `[jest-snapshot]` Downgrade semver to v6 to support node 8 ([#9451](https://github.com/facebook/jest/pull/9451))
+- `[jest-snapshot]` Properly indent new snapshots in the presences of existing ones ([#9523](https://github.com/facebook/jest/pull/9523))
 - `[jest-transform]` Correct sourcemap behavior for transformed and instrumented code ([#9460](https://github.com/facebook/jest/pull/9460))
 - `[pretty-format]` Export `OldPlugin` type ([#9491](https://github.com/facebook/jest/pull/9491))
 

e2e/__tests__/__snapshots__/toMatchInlineSnapshot.test.ts.snap

@@ -120,6 +120,22 @@ test('handles property matchers', () => {
 
 `;
 
+exports[`indentation is correct in the presences of existing snapshots: existing snapshot 1`] = `
+test('existing snapshot', () => {
+  expect({hello: 'world'}).toMatchInlineSnapshot(\`
+        Object {
+          "hello": "world",
+        }
+      \`);
+  expect({hello: 'world'}).toMatchInlineSnapshot(\`
+    Object {
+      "hello": "world",
+    }
+  \`);
+});
+
+`;
+
 exports[`multiple custom matchers and native matchers: multiple matchers 1`] = `
 const {toMatchInlineSnapshot} = require('jest-snapshot');
 expect.extend({

e2e/__tests__/toMatchInlineSnapshot.test.ts

@@ -360,3 +360,24 @@ test('multiple custom matchers and native matchers', () => {
   expect(exitCode).toBe(0);
   expect(wrap(fileAfter)).toMatchSnapshot('multiple matchers');
 });
+
+test('indentation is correct in the presences of existing snapshots', () => {
+  const filename = 'existing-snapshot.test.js';
+  const test = `
+    test('existing snapshot', () => {
+      expect({ hello: 'world' }).toMatchInlineSnapshot(\`
+        Object {
+          "hello": "world",
+        }
+      \`);
+      expect({ hello: 'world' }).toMatchInlineSnapshot();
+    });
+  `;
+
+  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');
+});

packages/jest-snapshot/src/inline_snapshots.ts

@@ -262,7 +262,7 @@ const createFormattingParser = (
       if (
         callee.type !== 'MemberExpression' ||
         callee.property.type !== 'Identifier' ||
-        callee.property.name !== snapshotMatcherNames[0] ||
+        !snapshotMatcherNames.includes(callee.property.name) ||
         !callee.loc ||
         callee.computed
       ) {
@@ -282,8 +282,6 @@ const createFormattingParser = (
         return;
       }
 
-      snapshotMatcherNames.shift();
-
       const useSpaces = !options.useTabs;
       snapshot = indent(
         snapshot,