refactor(expect): prepare for noUncheckedIndexedAccess (#4150)

* refactor(expect): prepare for `noUncheckedIndexedAccess` * test(expect): better error messages for missing mock call * test(expect): follow testing naming guidelines * tweak --------- Co-authored-by: Asher Gomez <ashersaupingomez@gmail.com>
denoland · Jan 11, 2024 · 508f3f5 · 508f3f5
1 parent a710c21
commit 508f3f5
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Showing 2 changed files with 19 additions and 4 deletions.
diff --git a/expect/_matchers.ts b/expect/_matchers.ts
@@ -542,7 +542,7 @@ export function toHaveBeenLastCalledWith(
 ): MatchResult {
   const calls = getMockCalls(context.value);
   const hasBeenCalled = calls.length > 0 &&
-    equal(calls[calls.length - 1].args, expected);
+    equal(calls.at(-1)?.args, expected);
 
   if (context.isNot) {
     if (hasBeenCalled) {
@@ -583,7 +583,7 @@ export function toHaveBeenNthCalledWith(
   const calls = getMockCalls(context.value);
   const callIndex = nth - 1;
   const hasBeenCalled = calls.length > callIndex &&
-    equal(calls[callIndex].args, expected);
+    equal(calls[callIndex]?.args, expected);
 
   if (context.isNot) {
     if (hasBeenCalled) {
@@ -596,7 +596,7 @@ export function toHaveBeenNthCalledWith(
   } else {
     if (!hasBeenCalled) {
       const nthCall = calls[callIndex];
-      if (!nth) {
+      if (!nthCall) {
         throw new AssertionError(
           `Expected the n-th call (n=${nth}) of mock function is with ${
             inspectArgs(expected)
@@ -689,7 +689,7 @@ export function toHaveLastReturnedWith(
   const calls = getMockCalls(context.value);
   const returned = calls.filter((call) => call.returns);
   const lastReturnedWithExpected = returned.length > 0 &&
-    equal(returned[returned.length - 1].returned, expected);
+    equal(returned.at(-1)?.returned, expected);
 
   if (context.isNot) {
     if (lastReturnedWithExpected) {

diff --git a/expect/_to_have_been_nth_called_with_test.ts b/expect/_to_have_been_nth_called_with_test.ts
@@ -27,3 +27,18 @@ Deno.test("expect().", () => {
     expect(mockFn).not.toHaveBeenNthCalledWith(2, 4, 5, 6);
   });
 });
+
+Deno.test("expect().toHaveBeenNthCalledWith() should throw when mock call does not exist", () => {
+  const mockFn = fn();
+
+  mockFn("hello");
+
+  expect(mockFn).toHaveBeenNthCalledWith(1, "hello");
+  assertThrows(
+    () => {
+      expect(mockFn).toHaveBeenNthCalledWith(2, "hello");
+    },
+    AssertionError,
+    'Expected the n-th call (n=2) of mock function is with "hello", but the n-th call does not exist.',
+  );
+});