Improve NoreturnContractCheck

delphi-checks/src/main/java/au/com/integradev/delphi/checks/LoopExecutingAtMostOnceCheck.java

@@ -23,6 +23,7 @@
 import au.com.integradev.delphi.cfg.api.Branch;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
 import au.com.integradev.delphi.cfg.api.Terminated;
+import au.com.integradev.delphi.cfg.api.Terminus;
 import au.com.integradev.delphi.utils.ControlFlowGraphUtils;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
@@ -244,7 +245,7 @@ private static boolean jumpsBeforeLoop(ControlFlowGraph cfg, Block loopBlock, De
         return true;
       }
       if ((search.getSuccessors().size() == 1 && search.getSuccessors().contains(jumpTarget))
-          || search.equals(cfg.getExitBlock())) {
+          || search instanceof Terminus) {
         return false;
       }
 

delphi-checks/src/main/java/au/com/integradev/delphi/checks/NoreturnContractCheck.java

@@ -20,8 +20,10 @@
 
 import au.com.integradev.delphi.cfg.api.Block;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
+import au.com.integradev.delphi.cfg.api.ExceptionalRoutineExit;
 import au.com.integradev.delphi.cfg.api.Finally;
 import au.com.integradev.delphi.cfg.api.PossibleException;
+import au.com.integradev.delphi.cfg.api.RoutineExit;
 import au.com.integradev.delphi.cfg.api.Terminated;
 import au.com.integradev.delphi.cfg.api.UnknownException;
 import au.com.integradev.delphi.cfg.block.TerminatorKind;
@@ -50,11 +52,11 @@ public DelphiCheckContext visit(RoutineImplementationNode routine, DelphiCheckCo
 
   private static boolean canReturnNormally(RoutineImplementationNode routine) {
     ControlFlowGraph cfg = ControlFlowGraphUtils.findContainingCFG(routine);
-    return cfg != null && canReturnNormally(cfg, cfg.getEntryBlock());
+    return cfg != null && canReturnNormally(cfg.getEntryBlock());
   }
 
-  private static boolean canReturnNormally(ControlFlowGraph cfg, Block block) {
-    if (block.equals(cfg.getExitBlock())) {
+  private static boolean canReturnNormally(Block block) {
+    if (block instanceof RoutineExit) {
       return true;
     }
 
@@ -63,18 +65,20 @@ private static boolean canReturnNormally(ControlFlowGraph cfg, Block block) {
     if (isGuaranteedException(block)) {
       successors =
           block.getSuccessors().stream()
-              .filter(s -> notFinallyOrExit(cfg, s))
+              .filter(NoreturnContractCheck::notFinallyOrExit)
               .collect(Collectors.toSet());
     } else if (block instanceof PossibleException) {
       successors = new HashSet<>();
       successors.add(((PossibleException) block).getSuccessor());
       ((PossibleException) block)
-          .getExceptions().stream().filter(s -> notFinallyOrExit(cfg, s)).forEach(successors::add);
+          .getExceptions().stream()
+              .filter(NoreturnContractCheck::notFinallyOrExit)
+              .forEach(successors::add);
     } else {
       successors = block.getSuccessors();
     }
 
-    return successors.stream().anyMatch(s -> canReturnNormally(cfg, s));
+    return successors.stream().anyMatch(NoreturnContractCheck::canReturnNormally);
   }
 
   private static boolean isGuaranteedException(Block block) {
@@ -83,7 +87,7 @@ private static boolean isGuaranteedException(Block block) {
             && ((Terminated) block).getTerminatorKind() == TerminatorKind.RAISE);
   }
 
-  private static boolean notFinallyOrExit(ControlFlowGraph cfg, Block block) {
-    return !(block instanceof Finally || block.equals(cfg.getExitBlock()));
+  private static boolean notFinallyOrExit(Block block) {
+    return !(block instanceof Finally || block instanceof ExceptionalRoutineExit);
   }
 }

delphi-checks/src/main/java/au/com/integradev/delphi/checks/RedundantJumpCheck.java

@@ -20,7 +20,9 @@
 
 import au.com.integradev.delphi.cfg.api.Block;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
+import au.com.integradev.delphi.cfg.api.ExceptionalRoutineExit;
 import au.com.integradev.delphi.cfg.api.Finally;
+import au.com.integradev.delphi.cfg.api.RoutineExit;
 import au.com.integradev.delphi.cfg.api.Terminated;
 import au.com.integradev.delphi.cfg.api.UnconditionalJump;
 import au.com.integradev.delphi.utils.ControlFlowGraphUtils;
@@ -134,7 +136,11 @@ private boolean isViolation(ControlFlowGraph cfg) {
       }
       if (!finallyBlock.getSuccessor().equals(finallyBlock.getExceptionSuccessor())) {
         // multiple paths after the finally corresponds to code that would be skipped from the jump
-        return false;
+        if (!(finallyBlock.getSuccessor() instanceof RoutineExit
+            && finallyBlock.getExceptionSuccessor() instanceof ExceptionalRoutineExit)) {
+          // if both of the paths are routine exits, then they are effectively equivalent
+          return false;
+        }
       }
     }
     // if no invalidating try-finally blocks are found, the use is a violation

delphi-checks/src/test/java/au/com/integradev/delphi/checks/NoreturnContractCheckTest.java

@@ -341,15 +341,15 @@ void testNoreturnRoutineWithRaiseToIrrelevantExceptShouldAddIssue() {
   }
 
   @Test
-  void testFailOnUpgradeNoreturnRoutineWithRaiseToSpecificEmptyExceptShouldNotAddIssue() {
+  void testNoreturnRoutineWithRaiseToSpecificEmptyExceptShouldAddIssue() {
     CheckVerifier.newVerifier()
         .withCheck(new NoreturnContractCheck())
         .onFile(
             new DelphiTestUnitBuilder()
                 .appendImpl("uses")
                 .appendImpl("  System.SysUtils;")
                 .appendImpl("")
-                .appendImpl("procedure RaiseToSpecificExcept; noreturn;")
+                .appendImpl("procedure RaiseToSpecificExcept; noreturn; // Noncompliant")
                 .appendImpl("begin")
                 .appendImpl("  try")
                 .appendImpl("    raise Exception.Create('Error');")
@@ -359,6 +359,6 @@ void testFailOnUpgradeNoreturnRoutineWithRaiseToSpecificEmptyExceptShouldNotAddI
                 .appendImpl("    end;")
                 .appendImpl("  end;")
                 .appendImpl("end;"))
-        .verifyNoIssues();
+        .verifyIssues();
   }
 }

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphBuilder.java

@@ -20,6 +20,8 @@
 
 import au.com.integradev.delphi.cfg.api.Block;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
+import au.com.integradev.delphi.cfg.api.ExceptionalRoutineExit;
+import au.com.integradev.delphi.cfg.api.RoutineExit;
 import au.com.integradev.delphi.cfg.block.BlockImpl;
 import au.com.integradev.delphi.cfg.block.ProtoBlock;
 import au.com.integradev.delphi.cfg.block.ProtoBlockFactory;
@@ -47,6 +49,7 @@
 public class ControlFlowGraphBuilder {
   private final List<ProtoBlock> blocks = new ArrayList<>();
   private final Deque<ProtoBlock> exitBlocks = new ArrayDeque<>();
+  private final Deque<ProtoBlock> exceptionalExitBlocks = new ArrayDeque<>();
   private final Deque<ProtoBlock> breakTargets = new ArrayDeque<>();
   private final Deque<ProtoBlock> continueTargets = new ArrayDeque<>();
   private final Map<String, ProtoBlock> labelTargets = new HashMap<>();
@@ -57,9 +60,14 @@ public class ControlFlowGraphBuilder {
 
   @SuppressWarnings("this-escape")
   public ControlFlowGraphBuilder() {
+    ProtoBlock exceptionalExitBlock = ProtoBlockFactory.exceptionalExitBlock();
+    addBlock(exceptionalExitBlock);
+    exceptionalExitBlocks.add(exceptionalExitBlock);
+
     ProtoBlock exitBlock = ProtoBlockFactory.exitBlock();
     addBlock(exitBlock);
     exitBlocks.add(exitBlock);
+
     addBlockBefore(exitBlock);
   }
 
@@ -73,8 +81,7 @@ public ControlFlowGraph build() {
     }
 
     ControlFlowGraphImpl cfg =
-        new ControlFlowGraphImpl(
-            map.get(currentBlock), map.get(exitBlocks.peek()), new ArrayList<>(map.values()));
+        new ControlFlowGraphImpl(map.get(currentBlock), new ArrayList<>(map.values()));
     cfg.prune();
 
     populatePredecessors(cfg);
@@ -93,15 +100,28 @@ private static void populatePredecessors(ControlFlowGraph cfg) {
 
   private static void populateIds(ControlFlowGraph cfg) {
     List<Block> blocks = Lists.reverse(cfg.getBlocks());
-    for (int blockId = 0; blockId < blocks.size(); blockId++) {
-      ((BlockImpl) blocks.get(blockId)).setId(blockId);
+    int blockId = 0;
+    for (Block block : blocks) {
+      if (block instanceof RoutineExit) {
+        // Ensure `RoutineExit` is always id 0
+        ((BlockImpl) block).setId(0);
+      } else if (block instanceof ExceptionalRoutineExit) {
+        // Ensure `ExceptionalRoutineExit` is always id -1
+        ((BlockImpl) block).setId(-1);
+      } else {
+        ((BlockImpl) block).setId(++blockId);
+      }
     }
   }
 
   public ProtoBlock getExitBlock() {
     return exitBlocks.peek();
   }
 
+  public ProtoBlock getExceptionalExitBlock() {
+    return exceptionalExitBlocks.peek();
+  }
+
   public ProtoBlock getBreakTarget() {
     return breakTargets.peek();
   }
@@ -110,6 +130,10 @@ public ProtoBlock getContinueTarget() {
     return continueTargets.peek();
   }
 
+  public boolean isInLoop() {
+    return !continueTargets.isEmpty();
+  }
+
   public void pushLoopContext(ProtoBlock continueTarget, ProtoBlock breakTarget) {
     continueTargets.push(continueTarget);
     breakTargets.push(breakTarget);
@@ -122,10 +146,12 @@ public void popLoopContext() {
 
   public void pushExitBlock(ProtoBlock target) {
     exitBlocks.push(target);
+    exceptionalExitBlocks.push(target);
   }
 
   public void popExitBlock() {
     exitBlocks.pop();
+    exceptionalExitBlocks.pop();
   }
 
   private static class UnresolvedLabel {
@@ -193,15 +219,15 @@ public boolean inTryContext() {
 
   public ProtoBlock getCatchTarget(Type exceptionType) {
     if (tryContexts.isEmpty()) {
-      return getExitBlock();
+      return getExceptionalExitBlock();
     }
     TryContext tryContext = tryContexts.peek();
     return tryContext.catches.keySet().stream()
         .filter(catchType -> isCompatibleType(exceptionType, catchType))
         .findFirst()
         .map(tryContext.catches::get)
         .or(() -> Optional.ofNullable(tryContext.elseBlock))
-        .orElse(getExitBlock());
+        .orElse(getExceptionalExitBlock());
   }
 
   private static boolean isCompatibleType(Type exceptionType, Type catchType) {
@@ -214,7 +240,7 @@ public Set<ProtoBlock> getAllCatchTargets() {
     }
     TryContext context = tryContexts.peek();
     Stream<ProtoBlock> elseOrExit =
-        Stream.of(Optional.ofNullable(context.elseBlock).orElse(getExitBlock()));
+        Stream.of(Optional.ofNullable(context.elseBlock).orElse(getExceptionalExitBlock()));
     return Stream.concat(context.catches.values().stream(), elseOrExit)
         .filter(Objects::nonNull)
         .collect(Collectors.toSet());

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphImpl.java

@@ -20,6 +20,7 @@
 
 import au.com.integradev.delphi.cfg.api.Block;
 import au.com.integradev.delphi.cfg.api.ControlFlowGraph;
+import au.com.integradev.delphi.cfg.api.ExceptionalRoutineExit;
 import au.com.integradev.delphi.cfg.api.Terminated;
 import au.com.integradev.delphi.cfg.api.UnconditionalJump;
 import au.com.integradev.delphi.cfg.block.BlockImpl;
@@ -32,12 +33,10 @@
 
 public class ControlFlowGraphImpl implements ControlFlowGraph {
   private Block entry;
-  private final Block exit;
   private final List<Block> blocks;
 
-  public ControlFlowGraphImpl(Block entry, Block exit, List<Block> blocks) {
+  public ControlFlowGraphImpl(Block entry, List<Block> blocks) {
     this.entry = entry;
-    this.exit = exit;
     this.blocks = blocks;
   }
 
@@ -46,11 +45,6 @@ public Block getEntryBlock() {
     return entry;
   }
 
-  @Override
-  public Block getExitBlock() {
-    return exit;
-  }
-
   @Override
   public List<Block> getBlocks() {
     return Collections.unmodifiableList(Lists.reverse(blocks));
@@ -75,6 +69,20 @@ public void prune() {
 
       blocks.forEach(inactiveBlocks::remove);
     } while (!inactiveBlocks.isEmpty());
+
+    // Remove the exceptional exit if there are no paths to it
+    Block exceptionalExitBlock =
+        Lists.reverse(blocks).stream()
+            .filter(ExceptionalRoutineExit.class::isInstance)
+            .findFirst()
+            .orElseThrow(
+                () -> new IllegalStateException("Couldn't find the exceptional exit block"));
+
+    if (blocks.stream()
+        .flatMap(block -> block.getSuccessors().stream())
+        .noneMatch(successor -> successor.equals(exceptionalExitBlock))) {
+      blocks.remove(exceptionalExitBlock);
+    }
   }
 
   private boolean isInactive(Block block) {

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/ControlFlowGraphVisitor.java

@@ -208,7 +208,7 @@ private static void handleExceptionalPaths(ControlFlowGraphBuilder builder) {
   private static Set<ProtoBlock> getUnknownExceptionTargets(ControlFlowGraphBuilder builder) {
     Set<ProtoBlock> exceptions = builder.getAllCatchTargets();
     if (exceptions.isEmpty()) {
-      return Set.of(builder.getExitBlock());
+      return Set.of(builder.getExceptionalExitBlock());
     }
     return exceptions;
   }
@@ -548,10 +548,13 @@ private ControlFlowGraphBuilder buildTryFinally(
     FinallyBlockNode finallyNode = node.getFinallyBlock();
     builder.addBlock(
         ProtoBlockFactory.finallyBlock(
-            node.getFinallyBlock(), builder.getCurrentBlock(), builder.getExitBlock()));
+            node.getFinallyBlock(), builder.getCurrentBlock(), builder.getExceptionalExitBlock()));
 
     build(finallyNode.getStatementList(), builder);
-    builder.pushLoopContext(builder.getCurrentBlock(), builder.getCurrentBlock());
+    boolean inLoop = builder.isInLoop();
+    if (inLoop) {
+      builder.pushLoopContext(builder.getCurrentBlock(), builder.getCurrentBlock());
+    }
     builder.pushExitBlock(builder.getCurrentBlock());
 
     builder.addBlockBeforeCurrent();
@@ -565,6 +568,9 @@ private ControlFlowGraphBuilder buildTryFinally(
     builder.addElement(node);
 
     builder.popExitBlock();
+    if (inLoop) {
+      builder.popLoopContext();
+    }
     return builder;
   }
 

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/api/ControlFlowGraph.java

@@ -29,13 +29,6 @@ public interface ControlFlowGraph {
    */
   Block getEntryBlock();
 
-  /**
-   * The final exit block of the control flow graph
-   *
-   * @return the final block of the control flow graph
-   */
-  Block getExitBlock();
-
   /**
    * All the blocks within the control flow graph
    *

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/api/ExceptionalRoutineExit.java

@@ -0,0 +1,22 @@
+/*
+ * Sonar Delphi Plugin
+ * Copyright (C) 2026 Integrated Application Development
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package au.com.integradev.delphi.cfg.api;
+
+/** A block representing an exceptional end of a routine, e.g., an uncaught exception */
+public interface ExceptionalRoutineExit extends Terminus {}

delphi-frontend/src/main/java/au/com/integradev/delphi/cfg/api/RoutineExit.java

@@ -0,0 +1,22 @@
+/*
+ * Sonar Delphi Plugin
+ * Copyright (C) 2026 Integrated Application Development
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
+ */
+package au.com.integradev.delphi.cfg.api;
+
+/** A block representing the end of a routine */
+public interface RoutineExit extends Terminus {}