Show the number of test cases that ran at the end of a test (#972)

### Motivation:

To have the number of test cases at the end of the test in for
parameterized tests, so the logs don’t easily get buried.

### Modifications:

Log the number of test cases for parameterized tests at the end of a
test.

### Result:

If the user runs the parameterized tests, an extra piece of information
(with * test cases) would get bound to the end log.

Resolves #943.

### Checklist:

- [x] Code and documentation should follow the style of the [Style
Guide](https://github.com/apple/swift-testing/blob/main/Documentation/StyleGuide.md).
- [x] If public symbols are renamed or modified, DocC references should
be updated.

Author: hrayatnia

Sources/Testing/Events/Recorder/Event.HumanReadableOutputRecorder.swift

@@ -62,6 +62,9 @@ extension Event {
 
         /// The number of known issues recorded for the test.
         var knownIssueCount = 0
+        
+        /// The number of test cases for the test.
+        var testCasesCount = 0
       }
 
       /// Data tracked on a per-test basis.
@@ -281,6 +284,10 @@ extension Event.HumanReadableOutputRecorder {
           testData.issueCount[issue.severity] = issueCount + 1
         }
         context.testData[id] = testData
+      
+      case .testCaseStarted:
+        let test = test!
+        context.testData[test.id.keyPathRepresentation]?.testCasesCount += 1
 
       default:
         // These events do not manipulate the context structure.
@@ -366,18 +373,23 @@ extension Event.HumanReadableOutputRecorder {
       let testData = testDataGraph?.value ?? .init(startInstant: instant)
       let issues = _issueCounts(in: testDataGraph)
       let duration = testData.startInstant.descriptionOfDuration(to: instant)
+      let testCasesCount = if test.isParameterized {
+        " with \(testData.testCasesCount.counting("test case"))"
+      } else {
+        ""
+      }
       return if issues.errorIssueCount > 0 {
         CollectionOfOne(
           Message(
             symbol: .fail,
-            stringValue: "\(_capitalizedTitle(for: test)) \(testName) failed after \(duration)\(issues.description)."
+            stringValue: "\(_capitalizedTitle(for: test)) \(testName)\(testCasesCount) failed after \(duration)\(issues.description)."
           )
         ) + _formattedComments(for: test)
       } else {
         [
           Message(
             symbol: .pass(knownIssueCount: issues.knownIssueCount),
-            stringValue: "\(_capitalizedTitle(for: test)) \(testName) passed after \(duration)\(issues.description)."
+            stringValue: "\(_capitalizedTitle(for: test)) \(testName)\(testCasesCount) passed after \(duration)\(issues.description)."
           )
         ]
       }

Tests/TestingTests/EventRecorderTests.swift

@@ -178,6 +178,44 @@ struct EventRecorderTests {
         .first != nil
     )
   }
+  
+  @available(_regexAPI, *)
+  @Test(
+    "Log the total number of test cases in parameterized tests at the end of the test run",
+    arguments: [
+      ("f()", #".* Test f\(\) failed after .*"#),
+      ("h()", #".* Test h\(\) passed after .+"#),
+      ("l(_:)", #".* Test l\(_:\) with .+ test cases passed after.*"#),
+      ("m(_:)", #".* Test m\(_:\) with .+ test cases failed after.*"#),
+      ("n(_:)", #".* Test n\(_:\) with .+ test case passed after.*"#),
+      ("PredictablyFailingTests", #".* Suite PredictablyFailingTests failed after .*"#),
+    ]
+  )
+  func numberOfTestCasesAtTestEnd(testName: String, expectedPattern: String) async throws {
+    let stream = Stream()
+
+    var configuration = Configuration()
+    let eventRecorder = Event.ConsoleOutputRecorder(writingUsing: stream.write)
+    configuration.eventHandler = { event, context in
+      eventRecorder.record(event, in: context)
+    }
+
+    await runTest(for: PredictablyFailingTests.self, configuration: configuration)
+
+    let buffer = stream.buffer.rawValue
+    if testsWithSignificantIOAreEnabled {
+      print(buffer, terminator: "")
+    }
+
+    let aurgmentRegex = try Regex(expectedPattern)
+    
+    #expect(
+      (try buffer
+        .split(whereSeparator: \.isNewline)
+        .compactMap(aurgmentRegex.wholeMatch(in:))
+        .first) != nil
+    )
+  }
 
   @available(_regexAPI, *)
   @Test(
@@ -189,7 +227,7 @@ struct EventRecorderTests {
       ("i()", #".* Test i\(\) failed after .+ seconds with 2 issues \(including 1 warning\)\."#),
       ("j()", #".* Test j\(\) passed after .+ seconds with 1 warning and 1 known issue\."#),
       ("k()", #".* Test k\(\) passed after .+ seconds with 1 known issue\."#),
-      ("PredictablyFailingTests", #".* Suite PredictablyFailingTests failed after .+ seconds with 13 issues \(including 3 warnings and 6 known issues\)\."#),
+      ("PredictablyFailingTests", #".* Suite PredictablyFailingTests failed after .+ seconds with 16 issues \(including 3 warnings and 6 known issues\)\."#),
     ]
   )
   func issueCountSummingAtTestEnd(testName: String, expectedPattern: String) async throws {
@@ -284,7 +322,7 @@ struct EventRecorderTests {
         .compactMap(runFailureRegex.wholeMatch(in:))
         .first
     )
-    #expect(match.output.1 == 9)
+    #expect(match.output.1 == 12)
     #expect(match.output.2 == 5)
   }
 
@@ -565,4 +603,19 @@ struct EventRecorderTests {
       Issue(kind: .unconditional, severity: .warning, comments: [], sourceContext: .init()).record()
     }
   }
+  
+  @Test(.hidden, arguments: [1, 2, 3])
+  func l(_ arg: Int) {
+    #expect(arg > 0)
+  }
+  
+  @Test(.hidden, arguments: [1, 2, 3])
+  func m(_ arg: Int) {
+      #expect(arg < 0)
+  }
+  
+  @Test(.hidden, arguments: [1])
+  func n(_ arg: Int) {
+    #expect(arg > 0)
+  }
 }