[jest-each] Fix each array title concatenation

CHANGELOG.md

@@ -6,6 +6,7 @@
 
 ### Fixes
 
+* `[jest-each]` Stop test title concatenating extra args ([##6346](https://github.com/facebook/jest/pull/#6346))
 * `[expect]` toMatchObject throws TypeError when a source property is null ([#6313](https://github.com/facebook/jest/pull/6313))
 * `[jest-cli]` Normalize slashes in paths in CLI output on Windows ([#6310](https://github.com/facebook/jest/pull/6310))
 

e2e/__tests__/__snapshots__/each.test.js.snap

@@ -29,7 +29,7 @@ exports[`shows error message when not enough arguments are supplied to tests 1`]
 
     Missing 1 arguments
 
-      at packages/jest-each/build/bind.js:81:17
+      at packages/jest-each/build/bind.js:82:17
 
 "
 `;

packages/jest-each/src/__tests__/array.test.js

@@ -72,23 +72,70 @@ describe('jest-each', () => {
         );
       });
 
-      test('calls global with title containing param values when using sprintf format', () => {
+      test('calls global with title containing param values when using printf format', () => {
         const globalTestMocks = getGlobalTestMocks();
         const eachObject = each.withGlobal(globalTestMocks)([
-          ['hello', 1],
-          ['world', 2],
+          [
+            'hello',
+            1,
+            null,
+            undefined,
+            1.2,
+            {foo: 'bar'},
+            () => {},
+            [],
+            Infinity,
+            NaN,
+          ],
+          [
+            'world',
+            1,
+            null,
+            undefined,
+            1.2,
+            {baz: 'qux'},
+            () => {},
+            [],
+            Infinity,
+            NaN,
+          ],
         ]);
         const testFunction = get(eachObject, keyPath);
-        testFunction('expected string: %s %s', noop);
+        testFunction('expected string: %s %d %s %s %d %j %s %j %d %d', noop);
 
         const globalMock = get(globalTestMocks, keyPath);
         expect(globalMock).toHaveBeenCalledTimes(2);
         expect(globalMock).toHaveBeenCalledWith(
-          'expected string: hello 1',
+          `expected string: hello 1 null undefined 1.2 ${JSON.stringify({
+            foo: 'bar',
+          })} () => {} [] Infinity NaN`,
           expectFunction,
         );
         expect(globalMock).toHaveBeenCalledWith(
-          'expected string: world 2',
+          `expected string: world 1 null undefined 1.2 ${JSON.stringify({
+            baz: 'qux',
+          })} () => {} [] Infinity NaN`,
+          expectFunction,
+        );
+      });
+
+      test('does not call global test with title containing more param values than sprintf placeholders', () => {
+        const globalTestMocks = getGlobalTestMocks();
+        const eachObject = each.withGlobal(globalTestMocks)([
+          ['hello', 1, 2, 3, 4, 5],
+          ['world', 1, 2, 3, 4, 5],
+        ]);
+        const testFunction = get(eachObject, keyPath);
+        testFunction('expected string: %s', noop);
+
+        const globalMock = get(globalTestMocks, keyPath);
+        expect(globalMock).toHaveBeenCalledTimes(2);
+        expect(globalMock).toHaveBeenCalledWith(
+          'expected string: hello',
+          expectFunction,
+        );
+        expect(globalMock).toHaveBeenCalledWith(
+          'expected string: world',
           expectFunction,
         );
       });

packages/jest-each/src/bind.js

@@ -15,6 +15,7 @@ type Table = Array<Array<any>>;
 
 const EXPECTED_COLOR = chalk.green;
 const RECEIVED_COLOR = chalk.red;
+const SUPPORTED_PLACEHOLDERS = /%[sdifjoO%]/g;
 
 export default (cb: Function) => (...args: any) => (
   title: string,
@@ -23,7 +24,7 @@ export default (cb: Function) => (...args: any) => (
   if (args.length === 1) {
     const table: Table = args[0];
     return table.forEach(row =>
-      cb(util.format(title, ...row), applyRestParams(row, test)),
+      cb(arrayFormat(title, ...row), applyRestParams(row, test)),
     );
   }
 
@@ -52,6 +53,11 @@ export default (cb: Function) => (...args: any) => (
   );
 };
 
+const arrayFormat = (str, ...args) => {
+  const matches = (str.match(SUPPORTED_PLACEHOLDERS) || []).length;
+  return util.format(str, ...args.slice(0, matches));
+};
+
 const applyRestParams = (params: Array<any>, test: Function) => {
   if (params.length < test.length) return done => test(...params, done);