Fix bugs with mock/spy result tracking of recursive functions.

CHANGELOG.md

@@ -61,6 +61,7 @@
 - `[jest-config]` Use strings instead of `RegExp` instances in normalized configuration ([#7251](https://github.com/facebook/jest/pull/7251))
 - `[jest-circus]` Make sure to display real duration even if time is mocked ([#7264](https://github.com/facebook/jest/pull/7264))
 - `[expect]` Improves the failing message for `toStrictEqual` matcher. ([#7224](https://github.com/facebook/jest/pull/7224))
+- `[jest-mock]` [**BREAKING**] Fix bugs with mock/spy result tracking of recursive functions ([#6381](https://github.com/facebook/jest/pull/6381)
 
 ### Chore & Maintenance
 
@@ -185,9 +186,6 @@
 ### Fixes
 
 - `[jest-haste-map]` Optimize watchman crawler by using `glob` on initial query ([#6689](https://github.com/facebook/jest/pull/6689))
-
-### Fixes
-
 - `[pretty-format]` Fix formatting of invalid Date objects ([#6635](https://github.com/facebook/jest/pull/6635))
 
 ## 23.4.0
@@ -348,7 +346,7 @@
 - `[jest-diff]` Support returning diff from oneline strings ([#6221](https://github.com/facebook/jest/pull/6221))
 - `[expect]` Improve return matchers ([#6172](https://github.com/facebook/jest/pull/6172))
 - `[jest-cli]` Overhaul watch plugin hooks names ([#6249](https://github.com/facebook/jest/pull/6249))
-- `[jest-mock]` Include tracked call results in serialized mock ([#6244](https://github.com/facebook/jest/pull/6244))
+- `[jest-mock]` [**BREAKING**] Include tracked call results in serialized mock ([#6244](https://github.com/facebook/jest/pull/6244))
 
 ### Fixes
 

docs/MockFunctionAPI.md

@@ -29,24 +29,30 @@ For example: A mock function `f` that has been called twice, with the arguments
 
 ### `mockFn.mock.results`
 
-An array containing the results of all calls that have been made to this mock function. Each entry in this array is an object containing a boolean `isThrow` property, and a `value` property. `isThrow` is true if the call terminated due to a `throw`, or false if the the call returned normally. The `value` property contains the value that was thrown or returned.
+An array containing the results of all calls that have been made to this mock function. Each entry in this array is an object containing a `type` property, and a `value` property. `type` will be one of the following:
 
-For example: A mock function `f` that has been called three times, returning `result1`, throwing an error, and then returning `result2`, would have a `mock.results` array that looks like this:
+- `'return'` - Indicates that the call completed by returning normally.
+- `'throw'` - Indicates that the call completed by throwing a value.
+- `'incomplete'` - Indicates that the call has not yet completed. This occurs if you test the result from within the mock function itself, or from within a function that was called by the mock.
+
+The `value` property contains the value that was thrown or returned. `value` is undefined when `type === 'incomplete'`.
+
+For example: A mock function `f` that has been called three times, returning `'result1'`, throwing an error, and then returning `'result2'`, would have a `mock.results` array that looks like this:
 
 ```js
 [
   {
-    isThrow: false,
+    type: 'return',
     value: 'result1',
   },
   {
-    isThrow: true,
+    type: 'throw',
     value: {
       /* Error instance */
     },
   },
   {
-    isThrow: false,
+    type: 'return',
     value: 'result2',
   },
 ];

packages/expect/src/__tests__/__snapshots__/spyMatchers.test.js.snap

@@ -149,6 +149,14 @@ Expected mock function \\"named-mock\\" to have last returned:
 But it was <red>not called</>"
 `;
 
+exports[`lastReturnedWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).lastReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function to have last returned:
+  <green>0</>
+But the last call <red>has not returned yet</>"
+`;
+
 exports[`lastReturnedWith works only on spies or jest.fn 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>)[.not].lastReturnedWith(</><dim>)</>
 
@@ -237,6 +245,15 @@ But the last call returned:
   <red>\\"foo\\"</>"
 `;
 
+exports[`lastReturnedWith works with three calls 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.lastReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function to not have last returned:
+  <green>\\"foo3\\"</>
+But it last returned exactly:
+  <red>\\"foo3\\"</>"
+`;
+
 exports[`lastReturnedWith works with undefined 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>).not.lastReturnedWith(</><green>expected</><dim>)</>
 
@@ -406,6 +423,40 @@ Expected mock function \\"named-mock\\" first call to have returned with:
 But it was <red>not called</>"
 `;
 
+exports[`nthReturnedWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).nthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function first call to have returned with:
+  <green>6</>
+But the first call <red>has not returned yet</>"
+`;
+
+exports[`nthReturnedWith incomplete recursive calls are handled properly 2`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).nthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function second call to have returned with:
+  <green>3</>
+But the second call <red>has not returned yet</>"
+`;
+
+exports[`nthReturnedWith incomplete recursive calls are handled properly 3`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.nthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function third call to not have returned with:
+  <green>1</>
+But the third call returned exactly:
+  <red>1</>"
+`;
+
+exports[`nthReturnedWith incomplete recursive calls are handled properly 4`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.nthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function 4th call to not have returned with:
+  <green>0</>
+But the 4th call returned exactly:
+  <red>0</>"
+`;
+
 exports[`nthReturnedWith should reject non integer nth value 1`] = `"nth value <red>0.1</> must be a positive integer greater than <green>0</>"`;
 
 exports[`nthReturnedWith should reject nth value greater than number of calls 1`] = `
@@ -1437,6 +1488,14 @@ Expected mock function \\"named-mock\\" to have last returned:
 But it was <red>not called</>"
 `;
 
+exports[`toHaveLastReturnedWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toHaveLastReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function to have last returned:
+  <green>0</>
+But the last call <red>has not returned yet</>"
+`;
+
 exports[`toHaveLastReturnedWith works only on spies or jest.fn 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>)[.not].toHaveLastReturnedWith(</><dim>)</>
 
@@ -1525,6 +1584,15 @@ But the last call returned:
   <red>\\"foo\\"</>"
 `;
 
+exports[`toHaveLastReturnedWith works with three calls 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.toHaveLastReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function to not have last returned:
+  <green>\\"foo3\\"</>
+But it last returned exactly:
+  <red>\\"foo3\\"</>"
+`;
+
 exports[`toHaveLastReturnedWith works with undefined 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>).not.toHaveLastReturnedWith(</><green>expected</><dim>)</>
 
@@ -1558,6 +1626,40 @@ Expected mock function \\"named-mock\\" first call to have returned with:
 But it was <red>not called</>"
 `;
 
+exports[`toHaveNthReturnedWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toHaveNthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function first call to have returned with:
+  <green>6</>
+But the first call <red>has not returned yet</>"
+`;
+
+exports[`toHaveNthReturnedWith incomplete recursive calls are handled properly 2`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toHaveNthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function second call to have returned with:
+  <green>3</>
+But the second call <red>has not returned yet</>"
+`;
+
+exports[`toHaveNthReturnedWith incomplete recursive calls are handled properly 3`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.toHaveNthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function third call to not have returned with:
+  <green>1</>
+But the third call returned exactly:
+  <red>1</>"
+`;
+
+exports[`toHaveNthReturnedWith incomplete recursive calls are handled properly 4`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.toHaveNthReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function 4th call to not have returned with:
+  <green>0</>
+But the 4th call returned exactly:
+  <red>0</>"
+`;
+
 exports[`toHaveNthReturnedWith should reject non integer nth value 1`] = `"nth value <red>0.1</> must be a positive integer greater than <green>0</>"`;
 
 exports[`toHaveNthReturnedWith should reject nth value greater than number of calls 1`] = `
@@ -1735,6 +1837,12 @@ Expected mock function \\"named-mock\\" not to have returned, but it returned:
   <red>42</>"
 `;
 
+exports[`toHaveReturned incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toHaveReturned(</><dim>)</>
+
+Expected mock function to have returned."
+`;
+
 exports[`toHaveReturned passes when at least one call does not throw 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>).not.toHaveReturned(</><dim>)</>
 
@@ -1850,6 +1958,12 @@ exports[`toHaveReturnedTimes includes the custom mock name in the error message
 Expected mock function \\"named-mock\\" to have returned <green>one time</>, but it returned <red>two times</>."
 `;
 
+exports[`toHaveReturnedTimes incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.toHaveReturnedTimes(</><green>2</><dim>)</>
+
+Expected mock function not to have returned <green>two times</>, but it returned exactly <red>two times</>."
+`;
+
 exports[`toHaveReturnedTimes only accepts a number argument 1`] = `
 "<dim>expect(</><red>received</><dim>)[.not].toHaveReturnedTimes(</><green>expected</><dim>)</>
 
@@ -1936,6 +2050,14 @@ Expected mock function \\"named-mock\\" to have returned:
 But it did <red>not return</>."
 `;
 
+exports[`toHaveReturnedWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toHaveReturnedWith(</><green>expected</><dim>)</>
+
+Expected mock function to have returned:
+  <green>undefined</>
+But it did <red>not return</>."
+`;
+
 exports[`toHaveReturnedWith works only on spies or jest.fn 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>)[.not].toHaveReturnedWith(</><dim>)</>
 
@@ -2093,6 +2215,12 @@ Expected mock function \\"named-mock\\" not to have returned, but it returned:
   <red>42</>"
 `;
 
+exports[`toReturn incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toReturn(</><dim>)</>
+
+Expected mock function to have returned."
+`;
+
 exports[`toReturn passes when at least one call does not throw 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>).not.toReturn(</><dim>)</>
 
@@ -2208,6 +2336,12 @@ exports[`toReturnTimes includes the custom mock name in the error message 1`] =
 Expected mock function \\"named-mock\\" to have returned <green>one time</>, but it returned <red>two times</>."
 `;
 
+exports[`toReturnTimes incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).not.toReturnTimes(</><green>2</><dim>)</>
+
+Expected mock function not to have returned <green>two times</>, but it returned exactly <red>two times</>."
+`;
+
 exports[`toReturnTimes only accepts a number argument 1`] = `
 "<dim>expect(</><red>received</><dim>)[.not].toReturnTimes(</><green>expected</><dim>)</>
 
@@ -2294,6 +2428,14 @@ Expected mock function \\"named-mock\\" to have returned:
 But it did <red>not return</>."
 `;
 
+exports[`toReturnWith incomplete recursive calls are handled properly 1`] = `
+"<dim>expect(</><red>jest.fn()</><dim>).toReturnWith(</><green>expected</><dim>)</>
+
+Expected mock function to have returned:
+  <green>undefined</>
+But it did <red>not return</>."
+`;
+
 exports[`toReturnWith works only on spies or jest.fn 1`] = `
 "<dim>expect(</><red>jest.fn()</><dim>)[.not].toReturnWith(</><dim>)</>