Merge pull request #106 from mircohacker/feature/add_full_stacktrace_to_error_message

Print full stack trace if verifyAllWhenMocksCalled fails

Author: timkindberg

src/when.js

@@ -2,7 +2,7 @@ const assert = require('assert')
 
 let registry = new Set()
 
-const getCallLine = () => (new Error()).stack.split('\n')[4]
+const getCallLines = () => (new Error()).stack.split('\n').slice(4).join('\n')
 
 /**
  * A hack to capture a reference to the `equals` jasmineUtil
@@ -73,7 +73,7 @@ class WhenMock {
       // * `once` mocks are used prioritized
       this.callMocks = this.callMocks
         .filter((callMock) => once || callMock.once || !equals(callMock.matchers, matchers))
-        .concat({ matchers, mockImplementation, expectCall, once, called: false, id: this.nextCallMockId, callLine: getCallLine() })
+        .concat({ matchers, mockImplementation, expectCall, once, called: false, id: this.nextCallMockId, callLines: getCallLines() })
         .sort((a, b) => {
           // Once mocks should appear before the rest
           if (a.once !== b.once) {
@@ -95,12 +95,12 @@ class WhenMock {
           let isMatch = false
 
           if (matchers && matchers[0] &&
-              // is a possible all args matcher object
-              (typeof matchers[0] === 'function' || typeof matchers[0] === 'object') &&
-              // ensure not a proxy
-              '_isAllArgsFunctionMatcher' in matchers[0] &&
-              // check for the special property name
-              matchers[0]._isAllArgsFunctionMatcher === true
+            // is a possible all args matcher object
+            (typeof matchers[0] === 'function' || typeof matchers[0] === 'object') &&
+            // ensure not a proxy
+            '_isAllArgsFunctionMatcher' in matchers[0] &&
+            // check for the special property name
+            matchers[0]._isAllArgsFunctionMatcher === true
           ) {
             if (matchers.length > 1) throw new Error('When using when.allArgs, it must be the one and only matcher provided to calledWith. You have incorrectly provided other matchers along with when.allArgs.')
             isMatch = checkArgumentMatchers(expectCall, [args])(true, matchers[0], 0)
@@ -224,11 +224,11 @@ const verifyAllWhenMocksCalled = () => {
   }, [[], [], []])
 
   const callLines = uncalledMocks
-    .filter(m => Boolean(m.callLine))
-    .map(m => `\n  ${String(m.callLine).trim()}`)
+    .filter(m => Boolean(m.callLines))
+    .map(m => `\n  ${String(m.callLines).trim()}`)
     .join('')
 
-  const msg = `Failed verifyAllWhenMocksCalled: ${uncalledMocks.length} not called at:${callLines}\n\n\n...rest of the stack...`
+  const msg = `Failed verifyAllWhenMocksCalled: ${uncalledMocks.length} not called: ${callLines}\n\n\n...rest of the stack...`
 
   assert.equal(`called mocks: ${calledMocks.length}`, `called mocks: ${allMocks.length}`, msg)
 }

src/when.test.js

@@ -109,6 +109,29 @@ describe('When', () => {
       expect(caughtErr.message).toMatch(/Failed verifyAllWhenMocksCalled: 2 not called/)
     })
 
+    it('should print a full stacktrace if verification check fails', () => {
+      const fn1 = jest.fn()
+
+      function extractedWhenConfiguration () {
+        when(fn1).expectCalledWith(expect.anything()).mockReturnValueOnce('z')
+      }
+
+      extractedWhenConfiguration()
+      extractedWhenConfiguration()
+
+      fn1(1)
+
+      let caughtErr
+
+      try {
+        verifyAllWhenMocksCalled()
+      } catch (e) {
+        caughtErr = e
+      }
+
+      expect(caughtErr.message).toContain('at Object.extractedWhenConfiguration')
+    })
+
     it('fails verification check if all mocks were not called with line numbers', () => {
       const fn1 = jest.fn()
       const fn2 = jest.fn()
@@ -121,8 +144,14 @@ describe('When', () => {
       fn1(1)
       fn2(1)
 
-      // Should be two call lines printed, hence the {2} at the end of the regex
-      expect(verifyAllWhenMocksCalled).toThrow(/(src(?:\\|\/)when\.test\.js:\d{3}(.|\s)*){2}/)
+      try {
+        verifyAllWhenMocksCalled()
+      } catch (e) {
+        const errorLines = e.message.split('\n')
+        const currentFilePathPattern = /src(?:\\|\/)when\.test\.js:\d{3}(.|\s)*/
+        const numberOfMatches = errorLines.filter(line => currentFilePathPattern.test(line)).length
+        expect(numberOfMatches).toBe(2)
+      }
     })
   })