Make error messages more explicit for toBeCalledWith assertions

jestjs · Jul 5, 2017 · 5b78d9b · 5b78d9b
1 parent a7acc5a
commit 5b78d9b
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Showing 4 changed files with 390 additions and 44 deletions.
diff --git a/packages/jest-matchers/src/__tests__/__snapshots__/spy_matchers.test.js.snap b/packages/jest-matchers/src/__tests__/__snapshots__/spy_matchers.test.js.snap
@@ -34,9 +34,7 @@ exports[`lastCalledWith works with Map 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).lastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}]</>
-But it was last called with:
-  <red>[Map {1 => 2, 2 => 1}]</>"
+  <green>Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}</> as argument 1, but it was called with <red>Map {1 => 2, 2 => 1}</>."
 `;
 
 exports[`lastCalledWith works with Set 1`] = `
@@ -50,18 +48,14 @@ exports[`lastCalledWith works with Set 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).lastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[Set {3, 4}]</>
-But it was last called with:
-  <red>[Set {1, 2}]</>"
+  <green>Set {3, 4}</> as argument 1, but it was called with <red>Set {1, 2}</>."
 `;
 
 exports[`lastCalledWith works with arguments that don't match 1`] = `
 "<dim>expect(<red>jest.fn()</><dim>).lastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was last called with:
-  <red>[\\"foo\\", \\"bar1\\"]</>"
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar1\\"</>."
 `;
 
 exports[`lastCalledWith works with arguments that match 1`] = `
@@ -82,10 +76,7 @@ exports[`lastCalledWith works with many arguments that don't match 1`] = `
 "<dim>expect(<red>jest.fn()</><dim>).lastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was last called with:
-  <red>[\\"foo\\", \\"bar3\\"]</>
-and <red>two more calls</>."
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar3\\"</>."
 `;
 
 exports[`toBeCalled works only on spies or jest.fn 1`] = `
@@ -262,9 +253,7 @@ exports[`toHaveBeenCalledWith works with Map 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been called with:
-  <green>[Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}]</>
-But it was called with:
-  <red>[Map {1 => 2, 2 => 1}]</>"
+  <green>Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}</> as argument 1, but it was called with <red>Map {1 => 2, 2 => 1}</>."
 `;
 
 exports[`toHaveBeenCalledWith works with Set 1`] = `
@@ -278,18 +267,14 @@ exports[`toHaveBeenCalledWith works with Set 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been called with:
-  <green>[Set {3, 4}]</>
-But it was called with:
-  <red>[Set {1, 2}]</>"
+  <green>Set {3, 4}</> as argument 1, but it was called with <red>Set {1, 2}</>."
 `;
 
 exports[`toHaveBeenCalledWith works with arguments that don't match 1`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was called with:
-  <red>[\\"foo\\", \\"bar1\\"]</>"
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar1\\"</>."
 `;
 
 exports[`toHaveBeenCalledWith works with arguments that match 1`] = `
@@ -310,9 +295,11 @@ exports[`toHaveBeenCalledWith works with many arguments that don't match 1`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was called with:
-  <red>[\\"foo\\", \\"bar3\\"]</>, <red>[\\"foo\\", \\"bar2\\"]</>, <red>[\\"foo\\", \\"bar1\\"]</>"
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar3\\"</>.
+
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar2\\"</>.
+
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar1\\"</>."
 `;
 
 exports[`toHaveBeenLastCalledWith works only on spies or jest.fn 1`] = `
@@ -349,9 +336,7 @@ exports[`toHaveBeenLastCalledWith works with Map 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenLastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}]</>
-But it was last called with:
-  <red>[Map {1 => 2, 2 => 1}]</>"
+  <green>Map {\\"a\\" => \\"b\\", \\"b\\" => \\"a\\"}</> as argument 1, but it was called with <red>Map {1 => 2, 2 => 1}</>."
 `;
 
 exports[`toHaveBeenLastCalledWith works with Set 1`] = `
@@ -365,18 +350,14 @@ exports[`toHaveBeenLastCalledWith works with Set 2`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenLastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[Set {3, 4}]</>
-But it was last called with:
-  <red>[Set {1, 2}]</>"
+  <green>Set {3, 4}</> as argument 1, but it was called with <red>Set {1, 2}</>."
 `;
 
 exports[`toHaveBeenLastCalledWith works with arguments that don't match 1`] = `
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenLastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was last called with:
-  <red>[\\"foo\\", \\"bar1\\"]</>"
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar1\\"</>."
 `;
 
 exports[`toHaveBeenLastCalledWith works with arguments that match 1`] = `
@@ -397,8 +378,5 @@ exports[`toHaveBeenLastCalledWith works with many arguments that don't match 1`]
 "<dim>expect(<red>jest.fn()</><dim>).toHaveBeenLastCalledWith(<green>expected</><dim>)
 
 Expected mock function to have been last called with:
-  <green>[\\"foo\\", \\"bar\\"]</>
-But it was last called with:
-  <red>[\\"foo\\", \\"bar3\\"]</>
-and <red>two more calls</>."
+  <green>\\"bar\\"</> as argument 2, but it was called with <red>\\"bar3\\"</>."
 `;
diff --git a/packages/jest-matchers/src/spy_matchers.js b/packages/jest-matchers/src/spy_matchers.js
@@ -24,7 +24,7 @@ import {
   RECEIVED_COLOR,
 } from 'jest-matcher-utils';
 import {equals} from './jasmine_utils';
-import {iterableEquality} from './utils';
+import {iterableEquality, partition} from './utils';
 
 const RECEIVED_NAME = {
   'mock function': 'jest.fn()',
@@ -69,7 +69,11 @@ const createToBeCalledWithMatcher = matcherName => (
   const calls = receivedIsSpy
     ? received.calls.all().map(x => x.args)
     : received.mock.calls;
-  const pass = calls.some(call => equals(call, expected, [iterableEquality]));
+
+  const [match, fail] = partition(calls, call =>
+    equals(call, expected, [iterableEquality]),
+  );
+  const pass = match.length > 0;
 
   const message = pass
     ? () =>
@@ -81,8 +85,7 @@ const createToBeCalledWithMatcher = matcherName => (
         matcherHint(matcherName, RECEIVED_NAME[type]) +
         '\n\n' +
         `Expected ${type} to have been called with:\n` +
-        `  ${printExpected(expected)}\n` +
-        formatReceivedCalls(calls, CALL_PRINT_LIMIT);
+        formatMismatchedCalls(fail, expected, CALL_PRINT_LIMIT);
 
   return {message, pass};
 };
@@ -110,8 +113,7 @@ const createLastCalledWithMatcher = matcherName => (
         matcherHint(matcherName, RECEIVED_NAME[type]) +
         '\n\n' +
         `Expected ${type} to have been last called with:\n` +
-        `  ${printExpected(expected)}\n` +
-        formatReceivedCalls(calls, LAST_CALL_PRINT_LIMIT, {isLast: true});
+        formatMismatchedCalls(calls, expected, LAST_CALL_PRINT_LIMIT);
 
   return {message, pass};
 };
@@ -198,4 +200,34 @@ const formatReceivedCalls = (calls, limit, options) => {
   }
 };
 
+const formatMismatchedCalls = (calls, expected, limit) => {
+  if (calls.length) {
+    return calls
+      .slice(-limit)
+      .reverse()
+      .map(formatMismatchedArgs.bind(null, expected))
+      .join('\n\n');
+  } else {
+    return (
+      `  ${printExpected(expected)}\n` +
+      `But it was ${RECEIVED_COLOR('not called')}.`
+    );
+  }
+};
+
+const formatMismatchedArgs = (expected, received) => {
+  const length = Math.max(expected.length, received.length);
+
+  const printedArgs = [];
+  for (let i = 0; i < length; i++) {
+    if (!equals(expected[i], received[i], [iterableEquality])) {
+      printedArgs.push(
+        `  ${printExpected(expected[i])} as argument ${i + 1}, ` +
+          `but it was called with ${printReceived(received[i])}.`,
+      );
+    }
+  }
+  return printedArgs.join('\n');
+};
+
 export default spyMatchers;
diff --git a/packages/jest-matchers/src/utils.js b/packages/jest-matchers/src/utils.js
@@ -123,3 +123,14 @@ export const iterableEquality = (a: any, b: any) => {
   }
   return true;
 };
+
+export const partition = <T>(
+  items: Array<T>,
+  predicate: T => boolean,
+): [Array<T>, Array<T>] => {
+  const result = [[], []];
+
+  items.forEach(item => result[predicate(item) ? 0 : 1].push(item));
+
+  return result;
+};