Implement toMatchInlineDiffSnapshot custom matcher

README.md

@@ -93,6 +93,13 @@ exports[`snapshot difference between 2 React components state 1`] = `
 `;
 ```
 
+### Inline Snapshots
+
+You might want to use inline snapshots.
+
+With a default matcher, you can use `toMatchInlineSnapshot` instead of
+`toMatchSnapshot`. With a custom matcher, you can use `toMatchInlineDiffSnapshot` instead of `toMatchDiffSnapshot`.
+
 ## Custom serializers
 
 By default, `snapshot-diff` uses a built in React serializer based on `react-test-renderer`. The

__tests__/toMatchInlineDiffSnapshot.test.js

@@ -0,0 +1,82 @@
+const snapshotDiff = require('../src/index');
+
+const a = `
+ some
+ some
+ some
+ some
+ some
+ some
+ some
+ not
+ very
+ long
+ script
+`;
+const b = `
+ some
+ some
+ some
+ some
+ some
+ some
+ some
+ not
+ so
+ very
+ long
+ script
+`;
+
+beforeAll(() => {
+ expect.extend({
+ toMatchInlineDiffSnapshot: snapshotDiff.toMatchInlineDiffSnapshot,
+ });
+});
+
+test('works with default options', () => {
+ expect(a).toMatchInlineDiffSnapshot(
+ b,
+ `
+ "Snapshot Diff:
+ - First value
+ + Second value
+
+ @@ -5,9 +5,10 @@
+ some
+ some
+ some
+ some
+ not
+ + so
+ very
+ long
+ script
+ "
+ `
+ );
+});
+
+test('works with non-default options', () => {
+ expect(a).toMatchInlineDiffSnapshot(
+ b,
+ { stablePatchmarks: true },
+ `
+ "Snapshot Diff:
+ - First value
+ + Second value
+
+ @@ --- --- @@
+ some
+ some
+ some
+ some
+ not
+ + so
+ very
+ long
+ script
+ "
+ `
+ );
+});

extend-expect.js

@@ -1,4 +1,4 @@
 /* global expect */
-const { toMatchDiffSnapshot } = require('./build/');
+const { toMatchDiffSnapshot, toMatchInlineDiffSnapshot } = require('./build/');
 
-expect.extend({ toMatchDiffSnapshot });
+expect.extend({ toMatchDiffSnapshot, toMatchInlineDiffSnapshot });

index.d.ts

@@ -40,6 +40,10 @@ declare module 'snapshot-diff' {
  * make it available via `expect.extend({ toMatchDiffSnapshot })`.
  */
  toMatchDiffSnapshot: jest.CustomMatcher;
+ /**
+ * Compare the changes from a to b with the diff inlined into tests
+ */
+ toMatchInlineDiffSnapshot: jest.CustomMatcher;
  /**
  * By default Jest adds extra quotes around strings so it makes diff
  * snapshots of objects too noisy. To fix this – snapshot-diff comes

src/index.js

@@ -91,6 +91,28 @@ function toMatchDiffSnapshot(
  return snapshot.toMatchSnapshot.call(this, difference, testName || '');
 }
 
+function toMatchInlineDiffSnapshot(
+ valueA: any,
+ valueB: any,
+ optionsOrSnapshot?: Options | string,
+ inlineSnapshot?: string
+) {
+ let options = undefined;
+ if (typeof optionsOrSnapshot === 'string') {
+ inlineSnapshot = optionsOrSnapshot;
+ } else {
+ options = optionsOrSnapshot;
+ }
+
+ const difference = snapshotDiff(valueA, valueB, options);
+
+ if (inlineSnapshot) {
+ return snapshot.toMatchInlineSnapshot.call(this, difference, inlineSnapshot);
+ } else {
+ return snapshot.toMatchInlineSnapshot.call(this, difference)
+ }
+}
+
 function getSnapshotDiffSerializer() {
  return {
  test(value: any) {
@@ -109,6 +131,7 @@ function setSerializers(customSerializers) {
 module.exports = snapshotDiff;
 module.exports.snapshotDiff = snapshotDiff;
 module.exports.toMatchDiffSnapshot = toMatchDiffSnapshot;
+module.exports.toMatchInlineDiffSnapshot = toMatchInlineDiffSnapshot;
 module.exports.getSnapshotDiffSerializer = getSnapshotDiffSerializer;
 module.exports.setSerializers = setSerializers;
 module.exports.defaultSerializers = defaultSerializers;