[FIR] Fix TEST SPEC tests

Ensure the test data contents for both the frontends
are identical. This is needed for proper analysis of
K2-differences.

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.1.fir.kt

@@ -1,5 +1,15 @@
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (NEGATIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 2
+ * NUMBER: 1
+ * DESCRIPTION: When with non-boolean value in the when condition.
+ * HELPERS: typesProvider
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: Int, value_2: String, value_3: TypesProvider): String {
     when {

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.fir.kt

@@ -1,5 +1,15 @@
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (NEGATIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 2
+ * NUMBER: 2
+ * DESCRIPTION: When without bound value, forbidden comma in the when condition.
+ * HELPERS: typesProvider, classes
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: TypesProvider) {
     when {

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/neg/2.2.kt

@@ -13,8 +13,8 @@
 // TESTCASE NUMBER: 1
 fun case_1(value_1: TypesProvider) {
     when {
-        getBoolean()<!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> value_1.getBoolean()  -> return 
-        value_1.getBoolean() && getBoolean()<!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> getLong() == 1000L -> return 
+        getBoolean()<!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> value_1.getBoolean()  -> return
+        value_1.getBoolean() && getBoolean()<!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> getLong() == 1000L -> return
         <!TYPE_MISMATCH!>Out<Int>()<!><!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> <!TYPE_MISMATCH!>getLong()<!><!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> <!TYPE_MISMATCH!>{}<!><!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> <!TYPE_MISMATCH!>Any()<!><!COMMA_IN_WHEN_CONDITION_WITHOUT_ARGUMENT!>,<!> throw Exception() -> return
     }
 

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/pos/1.1.fir.kt

@@ -1,6 +1,17 @@
+// LANGUAGE: +WarnAboutNonExhaustiveWhenOnAlgebraicTypes
 // !DIAGNOSTICS: -UNUSED_EXPRESSION -DEBUG_INFO_SMARTCAST
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 1
+ * NUMBER: 1
+ * DESCRIPTION: When without bound value, various expressions in the control structure body.
+ * HELPERS: typesProvider, classes, functions
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: Int) {
     when {
@@ -60,11 +71,14 @@ fun case_5(value_1: Int, value_2: Int, value_3: Boolean?) {
             false -> "2"
             null -> "3"
         }
-        value_1 == 5 -> <!NO_ELSE_IN_WHEN!>when<!> (value_3) {
+        value_1 == 5 -> when (value_3) {
             true -> "1"
             false -> "2"
+            else -> ""
+        }
+        value_1 == 6 -> when (value_3) {
+            else -> ""
         }
-        value_1 == 6 -> <!NO_ELSE_IN_WHEN!>when<!> (value_3) {}
     }
 }
 
@@ -108,7 +122,6 @@ fun case_8(value_1: Int, value_2: Int) = when {
 
 /*
  * TESTCASE NUMBER: 9
- * UNEXPECTED BEHAVIOUR
  * ISSUES: KT-37249
  */
 fun case_9(value_1: Int, value_2: String, value_3: String) = when {

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/pos/1.2.fir.kt

@@ -1,5 +1,14 @@
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 1
+ * NUMBER: 2
+ * DESCRIPTION: Allowed break and continue in the control structure body of when.
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: Int): String {
     while (true) {

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/pos/2.1.fir.kt

@@ -1,5 +1,15 @@
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 2
+ * NUMBER: 1
+ * DESCRIPTION: When without bound value, various boolean values in the when condition.
+ * HELPERS: typesProvider, enumClasses, sealedClasses, classes
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: Boolean, value_2: Long): Int {
     return when {

compiler/tests-spec/testData/diagnostics/linked/expressions/when-expression/p-2/pos/2.3.fir.kt

@@ -1,5 +1,17 @@
 // SKIP_TXT
 
+/*
+ * KOTLIN DIAGNOSTICS SPEC TEST (POSITIVE)
+ *
+ * SPEC VERSION: 0.1-100
+ * MAIN LINK: expressions, when-expression -> paragraph 2 -> sentence 2
+ * NUMBER: 3
+ * DESCRIPTION: 'When' without bound value and with Nothing in condition (subtype of Boolean).
+ * DISCUSSION
+ * ISSUES: KT-25948
+ * HELPERS: typesProvider
+ */
+
 // TESTCASE NUMBER: 1
 fun case_1(value_1: TypesProvider) {
     when {