assert: show thrown message in doesNotThrow()

assert.doesNotThrow() should show actual error message instead of "Got unwanted exception" which is not really helpful. PR-URL: nodejs#12167 Reviewed-By: Anna Henningsen <[email protected]> Reviewed-By: Yuta Hiroto <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Joyee Cheung <[email protected]> Reviewed-By: Refael Ackermann <[email protected]>
refack · Jul 9, 2017 · 7011772 · 7011772
1 parent 1b2733f
commit 7011772
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Showing 2 changed files with 18 additions and 5 deletions.
diff --git a/lib/assert.js b/lib/assert.js
@@ -517,7 +517,7 @@ function tryBlock(block) {
   }
 }
 
-function innerThrows(shouldThrow, block, expected, message) {
+function innerThrows(shouldThrow, block, expected, message, caller) {
   var details = '';
 
   if (typeof block !== 'function') {
@@ -538,27 +538,32 @@ function innerThrows(shouldThrow, block, expected, message) {
         details += ` (${expected.name})`;
       }
       details += message ? `: ${message}` : '.';
-      fail(actual, expected, `Missing expected exception${details}`, fail);
+      fail(actual, expected, `Missing expected exception${details}`, caller);
     }
     if (expected && expectedException(actual, expected) === false) {
       throw actual;
     }
   } else if (actual !== undefined) {
     if (!expected || expectedException(actual, expected)) {
       details = message ? `: ${message}` : '.';
-      fail(actual, expected, `Got unwanted exception${details}`, fail);
+      fail(
+        actual,
+        expected,
+        `Got unwanted exception${details}\n${actual.message}`,
+        caller
+      );
     }
     throw actual;
   }
 }
 
 // Expected to throw an error.
 assert.throws = function throws(block, error, message) {
-  innerThrows(true, block, error, message);
+  innerThrows(true, block, error, message, throws);
 };
 
 assert.doesNotThrow = function doesNotThrow(block, error, message) {
-  innerThrows(false, block, error, message);
+  innerThrows(false, block, error, message, doesNotThrow);
 };
 
 assert.ifError = function ifError(err) { if (err) throw err; };
diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js
@@ -468,6 +468,14 @@ assert.throws(() => {
 }, /Got unwanted exception: user message/,
               'a.doesNotThrow ignores user message');
 
+assert.throws(() => {
+  assert.doesNotThrow(makeBlock(thrower, Error), 'user message');
+}, /Got unwanted exception: user message\ntest/);
+
+assert.throws(() => {
+  assert.doesNotThrow(makeBlock(thrower, Error));
+}, /Got unwanted exception\.\ntest/);
+
 // make sure that validating using constructor really works
 {
   let threw = false;