#801 Allow gaps between segment redefined fields as long as they have a single common base redefine.

Author: yruslan

cobol-parser/src/main/scala/za/co/absa/cobrix/cobol/parser/asttransform/SegmentRedefinesMarker.scala

@@ -72,11 +72,20 @@ class SegmentRedefinesMarker(segmentRedefines: Seq[String]) extends AstTransform
             if (foundRedefines.contains(g.name)) {
               throw new IllegalStateException(s"Duplicate segment redefine field '${g.name}' found.")
             }
+
+            if (redefineGroupState == 1 && g.redefines.isEmpty)
+              throw new IllegalStateException(s"The segment redefine field '${g.name}' is not a REDEFINE or redefined by another field.")
+
             ensureSegmentRedefinesAreIneGroup(g.name, isCurrentFieldASegmentRedefine = true)
             foundRedefines += g.name
             g.withUpdatedIsSegmentRedefine(true)
           } else {
-            ensureSegmentRedefinesAreIneGroup(g.name, isCurrentFieldASegmentRedefine = false)
+            // Allow redefines in between segment redefines.
+            val fieldMightBeRedefine = if (redefineGroupState == 1 && g.redefines.nonEmpty)
+              true
+            else
+              false
+            ensureSegmentRedefinesAreIneGroup(g.name, isCurrentFieldASegmentRedefine = fieldMightBeRedefine)
             // Check nested fields recursively only if segment redefines hasn't been found so far.
             if (redefineGroupState == 0) {
               processGroupFields(g)

cobol-parser/src/test/scala/za/co/absa/cobrix/cobol/parser/parse/SegmentRedefinesSpec.scala

@@ -88,6 +88,33 @@ class SegmentRedefinesSpec extends AnyFunSuite {
     assert(!parsedCopybook.ast.children.head.asInstanceOf[Group].children(4).asInstanceOf[Group].isSegmentRedefine)
   }
 
+  test ("Test allow gaps in segment redefines as long as they are in the same group") {
+    val copybook =
+      """      01 RECORD.
+        |        02 A-RECORD.
+        |           03 FIELD0 PIC X(2).
+        |        02 SEGMENT-A.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-B REDEFINES SEGMENT-A.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-C REDEFINES SEGMENT-A.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 SEGMENT-D REDEFINES SEGMENT-A.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 Z-RECORD.
+        |           03 FIELD5 PIC X(2).
+      """.stripMargin
+
+    val segmentRedefines = "SEGMENT-A" :: "SEGMENT-C" :: "SEGMENT-D" :: Nil
+
+    val parsedCopybook = CopybookParser.parseTree(copybook, dropGroupFillers = false, dropValueFillers = true, fillerNamingPolicy = FillerNamingPolicy.SequenceNumbers, segmentRedefines)
+
+    assert(!parsedCopybook.ast.children.head.asInstanceOf[Group].children(0).asInstanceOf[Group].isSegmentRedefine)
+    assert(parsedCopybook.ast.children.head.asInstanceOf[Group].children(1).asInstanceOf[Group].isSegmentRedefine)
+    assert(!parsedCopybook.ast.children.head.asInstanceOf[Group].children(2).asInstanceOf[Group].isSegmentRedefine)
+    assert(parsedCopybook.ast.children.head.asInstanceOf[Group].children(3).asInstanceOf[Group].isSegmentRedefine)
+  }
+
   test ("Test segment redefines should be in the same redefined group") {
     val copybook =
       """      01 RECORD.
@@ -115,5 +142,55 @@ class SegmentRedefinesSpec extends AnyFunSuite {
     assert(exception1.getMessage.contains("The 'SEGMENT_C' field is specified to be a segment redefine."))
   }
 
+  test ("Test first segment should be redefined") {
+    val copybook =
+      """      01 RECORD.
+        |        02 A-RECORD.
+        |           03 FIELD0 PIC X(2).
+        |        02 SEGMENT-A.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-B.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-C  REDEFINES SEGMENT-B.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 SEGMENT-D REDEFINES SEGMENT-C.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 Z-RECORD.
+        |           03 FIELD5 PIC X(2).
+      """.stripMargin
+
+    val segmentRedefines = "SEGMENT-A" :: "SEGMENT-B" :: "SEGMENT-C" :: "SEGMENT-D" :: Nil
+
+    val exception1 = intercept[IllegalStateException] {
+      CopybookParser.parseTree(copybook, dropGroupFillers = false, dropValueFillers = true, fillerNamingPolicy = FillerNamingPolicy.SequenceNumbers, segmentRedefines)
+    }
+    assert(exception1.getMessage.contains("The following segment redefines not found: [ SEGMENT_A ]."))
+  }
+
+  test ("Test don't allow non-redefined fields in between segment redefines") {
+    val copybook =
+      """      01 RECORD.
+        |        02 A-RECORD.
+        |           03 FIELD0 PIC X(2).
+        |        02 SEGMENT-A.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-B REDEFINES SEGMENT-A.
+        |           03 FIELD1 PIC X(2).
+        |        02 SEGMENT-C.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 SEGMENT-D REDEFINES SEGMENT-C.
+        |           03 FIELD4 PICTURE S9(6)USAGE COMP.
+        |        02 Z-RECORD.
+        |           03 FIELD5 PIC X(2).
+      """.stripMargin
+
+    val segmentRedefines = "SEGMENT-A" :: "SEGMENT-B" :: "SEGMENT-C" :: "SEGMENT-D" :: Nil
+
+    val exception1 = intercept[IllegalStateException] {
+      CopybookParser.parseTree(copybook, dropGroupFillers = false, dropValueFillers = true, fillerNamingPolicy = FillerNamingPolicy.SequenceNumbers, segmentRedefines)
+    }
+    assert(exception1.getMessage.contains("The segment redefine field 'SEGMENT_C' is not a REDEFINE or redefined by another field."))
+  }
+
 
 }