Add assertion messages (#204)

src/junitxml.ts

@@ -9,23 +9,23 @@ export type JunitXml = {
 }
 
 function assertJunitXml(x: unknown): asserts x is JunitXml {
-  assert(typeof x === 'object')
-  assert(x != null)
+  assert(typeof x === 'object', 'root document must be an object')
+  assert(x != null, 'root document must not be null')
 
   if ('testsuites' in x) {
-    assert(typeof x.testsuites === 'object')
-    assert(x.testsuites != null)
+    assert(typeof x.testsuites === 'object', 'testsuites must be an object')
+    assert(x.testsuites != null, 'testsuites must not be null')
 
     if ('testsuite' in x.testsuites) {
-      assert(Array.isArray(x.testsuites.testsuite))
+      assert(Array.isArray(x.testsuites.testsuite), 'testsuite must be an array')
       for (const testsuite of x.testsuites.testsuite) {
         assertTestSuite(testsuite)
       }
     }
   }
 
   if ('testsuite' in x) {
-    assert(Array.isArray(x.testsuite))
+    assert(Array.isArray(x.testsuite), 'testsuite must be an array')
     for (const testsuite of x.testsuite) {
       assertTestSuite(testsuite)
     }
@@ -40,21 +40,21 @@ export type TestSuite = {
 }
 
 function assertTestSuite(x: unknown): asserts x is TestSuite {
-  assert(typeof x === 'object')
-  assert(x != null)
-  assert('@_name' in x)
-  assert(typeof x['@_name'] === 'string')
-  assert('@_time' in x)
-  assert(typeof x['@_time'] === 'number')
+  assert(typeof x === 'object', 'testsuite must be an object')
+  assert(x != null, 'testsuite must not be null')
+  assert('@_name' in x, 'testsuite must have name attribute')
+  assert(typeof x['@_name'] === 'string', 'name attribute must be a string')
+  assert('@_time' in x, 'testsuite must have time attribute')
+  assert(typeof x['@_time'] === 'number', 'time attribute must be a number')
 
   if ('testsuite' in x) {
-    assert(Array.isArray(x.testsuite))
+    assert(Array.isArray(x.testsuite), 'testsuite must be an array')
     for (const testsuite of x.testsuite) {
       assertTestSuite(testsuite)
     }
   }
   if ('testcase' in x) {
-    assert(Array.isArray(x.testcase))
+    assert(Array.isArray(x.testcase), 'testcase must be an array')
     for (const testcase of x.testcase) {
       assertTestCase(testcase)
     }
@@ -75,31 +75,31 @@ export type TestCase = {
 }
 
 function assertTestCase(x: unknown): asserts x is TestCase {
-  assert(typeof x === 'object')
-  assert(x != null)
-  assert('@_name' in x)
-  assert(typeof x['@_name'] === 'string')
-  assert('@_time' in x)
-  assert(typeof x['@_time'] === 'number')
+  assert(typeof x === 'object', 'testcase must be an object')
+  assert(x != null, 'testcase must not be null')
+  assert('@_name' in x, 'testcase must have name attribute')
+  assert(typeof x['@_name'] === 'string', 'name attribute must be a string')
+  assert('@_time' in x, 'testcase must have time attribute')
+  assert(typeof x['@_time'] === 'number', 'time attribute must be a number')
 
   if ('@_classname' in x) {
-    assert(typeof x['@_classname'] === 'string')
+    assert(typeof x['@_classname'] === 'string', 'classname attribute must be a string')
   }
   if ('@_file' in x) {
-    assert(typeof x['@_file'] === 'string')
+    assert(typeof x['@_file'] === 'string', 'file attribute must be a string')
   }
   if ('failure' in x) {
-    assert(typeof x.failure === 'object')
-    assert(x.failure != null)
+    assert(typeof x.failure === 'object', 'failure must be an object')
+    assert(x.failure != null, 'failure must not be null')
     if ('@_message' in x.failure) {
-      assert(typeof x.failure['@_message'] === 'string')
+      assert(typeof x.failure['@_message'] === 'string', 'message attribute of failure element must be a string')
     }
   }
   if ('error' in x) {
-    assert(typeof x.error === 'object')
-    assert(x.error != null)
+    assert(typeof x.error === 'object', 'error must be an object')
+    assert(x.error != null, 'error must not be null')
     if ('@_message' in x.error) {
-      assert(typeof x.error['@_message'] === 'string')
+      assert(typeof x.error['@_message'] === 'string', 'message attribute of error element must be a string')
     }
   }
 }