Fix #3394: Validating Kdoc ending sequence (#5622)

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Fix #3394
Updated the `file_content_checks` to validate against
`\\*(\\s*\\*|\\*)/` for KDoc and block comment endings. This change
ensures the script correctly detects improperly formatted endings, such
as those with multiple asterisks or unnecessary whitespace before the
closing /.

Additionally, updated the existing incorrect KDoc endings flagged by the
RegexPatternValidationCheck.kt script to conform to the correct format.
## Essential Checklist
<!-- Please tick the relevant boxes by putting an "x" in them. -->
- [x] The PR title and explanation each start with "Fix #bugnum: " (If
this PR fixes part of an issue, prefix the title with "Fix part of
#bugnum: ...".)
- [x] Any changes to
[scripts/assets](https://github.com/oppia/oppia-android/tree/develop/scripts/assets)
files have their rationale included in the PR explanation.
- [x] The PR follows the [style
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app/src/main/java/org/oppia/android/app/player/audio/LanguageInterface.kt

@@ -11,7 +11,7 @@ interface LanguageInterface {
   /**
    * Returns whether the user is actively seeking a new audio position, that is, dragging the
    * knob to a new position in the audio track.
-   * */
+   */
   fun getUserIsSeeking(): Boolean
 
   /** Returns the position of the knob on the audio track. */

app/src/main/java/org/oppia/android/app/shim/IntentFactoryShim.kt

@@ -16,7 +16,7 @@ interface IntentFactoryShim {
   /**
    * Creates a [TopicActivity] intent for [PromotedStoryViewModel] and passes necessary string
    * data.
-   * */
+   */
   fun createTopicPlayStoryActivityIntent(
     context: Context,
     internalProfileId: Int,
@@ -27,7 +27,7 @@ interface IntentFactoryShim {
 
   /**
    * Creates a [TopicActivity] intent which opens info-tab.
-   * */
+   */
   fun createTopicActivityIntent(
     context: Context,
     internalProfileId: Int,

app/src/main/java/org/oppia/android/app/story/StoryFragmentScroller.kt

@@ -4,6 +4,6 @@ interface StoryFragmentScroller {
   /**
    * Scrolls smoothly (with animation) to the specified vertical pixel position in
    * [StoryFragment].
-   * */
+   */
   fun smoothScrollToPosition(position: Int)
 }

domain/src/main/java/org/oppia/android/domain/hintsandsolution/HintHandler.kt

@@ -35,7 +35,7 @@ interface HintHandler {
    * @param trackedWrongAnswerCount the count of wrong answers saved in the checkpoint
    * @param helpIndex the cached state of hints/solution from the checkpoint
    * @param state the restored pending state
-   * */
+   */
   suspend fun resumeHintsForSavedState(
     trackedWrongAnswerCount: Int,
     helpIndex: HelpIndex,

domain/src/main/java/org/oppia/android/domain/oppialogger/exceptions/ExceptionsController.kt

@@ -113,7 +113,7 @@ class ExceptionsController @Inject constructor(
    * At first, it checks if the size of the store isn't exceeding [exceptionLogStorageCacheSize].
    * If the limit is exceeded then the least recent exception is removed from the [exceptionLogStore].
    * After this, the [exceptionLog] is added to the store.
-   * */
+   */
   private fun cacheExceptionLog(exceptionLog: ExceptionLog) {
     exceptionLogStore.storeDataAsync(true) { oppiaExceptionLogs ->
       val storeSize = oppiaExceptionLogs.exceptionLogList.size

scripts/assets/file_content_validation_checks.textproto

@@ -503,8 +503,8 @@ file_content_checks {
 }
 file_content_checks {
   file_path_regex: ".+?\\.kt$"
-  prohibited_content_regex: "\\*\\*/"
-  failure_message: "Badly formatted KDoc or block comment. KDocs and block comments should only end with \"*/\"."
+  prohibited_content_regex: "\\*(\\s*\\*|\\*)/"
+  failure_message: "Badly formatted KDoc or block comment. KDocs and block comments should only end with \"*/\". Multiple asterisks or whitespace between asterisks are not allowed."
   exempted_file_name: "scripts/src/javatests/org/oppia/android/scripts/regex/RegexPatternValidationCheckTest.kt"
 }
 file_content_checks {

scripts/src/javatests/org/oppia/android/scripts/regex/RegexPatternValidationCheckTest.kt

@@ -206,7 +206,8 @@ class RegexPatternValidationCheckTest {
     "Badly formatted KDoc. Single-line KDocs should always end with exactly one space before the" +
       " final \"*/\"."
   private val badKdocOrBlockCommentShouldEndWithCorrectEnding =
-    "Badly formatted KDoc or block comment. KDocs and block comments should only end with \"*/\"."
+    "Badly formatted KDoc or block comment. KDocs and block comments should only" +
+      " end with \"*/\". Multiple asterisks or whitespace between asterisks are not allowed."
   private val badKdocParamsAndPropertiesShouldHaveNameFollowing =
     "Badly formatted KDoc param or property at-clause: the name of the parameter or property" +
       " should immediately follow the at-clause without any additional linking with brackets."
@@ -2607,6 +2608,37 @@ class RegexPatternValidationCheckTest {
       )
   }
 
+  @Test
+  fun testFileContent_kdocWithInvalidEndingSequences_failsValidation() {
+    val prohibitedContent =
+      """
+      /**
+       * Incorrect KDoc comment.
+       * */
+       /**
+       * Incorrect KDoc comment.
+       **/
+       /**
+         * Correct KDoc comment.
+         */
+      """.trimIndent()
+    tempFolder.newFolder("testfiles", "app", "src", "main", "java", "org", "oppia", "android")
+    val stringFilePath = "app/src/main/java/org/oppia/android/TestPresenter.kt"
+    tempFolder.newFile("testfiles/$stringFilePath").writeText(prohibitedContent)
+
+    val exception = assertThrows<Exception>() { runScript() }
+
+    assertThat(exception).hasMessageThat().contains(REGEX_CHECK_FAILED_OUTPUT_INDICATOR)
+    assertThat(outContent.toString().trim())
+      .isEqualTo(
+        """
+      $stringFilePath:3: $badKdocOrBlockCommentShouldEndWithCorrectEnding
+      $stringFilePath:6: $badKdocOrBlockCommentShouldEndWithCorrectEnding
+      $wikiReferenceNote
+        """.trimIndent()
+      )
+  }
+
   @Test
   fun testFileContent_singleLineKdocWithExtraSpacesBeforeEnd_fileContentIsNotCorrect() {
     val prohibitedContent =