Merge pull request #325 from hjotha/refactor/builder-extract-anchor-helpers

refactor: extract microflow anchor selection helpers

Author: ako

mdl/executor/cmd_microflows_builder_control.go

@@ -125,10 +125,7 @@ func (fb *flowBuilder) addIfStatement(s *ast.IfStmt) model.ID {
 					// Destination: prefer the first statement's own @anchor(to: ...) if it
 					// has one; otherwise fall back to trueBranchAnchor.To.
 					flow := newHorizontalFlowWithCase(splitID, actID, "true")
-					applyUserAnchors(flow, trueBranchAnchor, trueBranchAnchor)
-					if thisAnchor != nil && thisAnchor.To != ast.AnchorSideUnset {
-						flow.DestinationConnectionIndex = int(thisAnchor.To)
-					}
+					applyUserAnchors(flow, trueBranchAnchor, branchDestinationAnchor(trueBranchAnchor, thisAnchor))
 					fb.flows = append(fb.flows, flow)
 				} else {
 					flow := newHorizontalFlow(lastThenID, actID)
@@ -180,10 +177,7 @@ func (fb *flowBuilder) addIfStatement(s *ast.IfStmt) model.ID {
 					// First statement in ELSE - connect from split going down (false path).
 					// Same compositional rule as the THEN branch.
 					flow := newDownwardFlowWithCase(splitID, actID, "false")
-					applyUserAnchors(flow, falseBranchAnchor, falseBranchAnchor)
-					if thisAnchor != nil && thisAnchor.To != ast.AnchorSideUnset {
-						flow.DestinationConnectionIndex = int(thisAnchor.To)
-					}
+					applyUserAnchors(flow, falseBranchAnchor, branchDestinationAnchor(falseBranchAnchor, thisAnchor))
 					fb.flows = append(fb.flows, flow)
 				} else {
 					flow := newHorizontalFlow(lastElseID, actID)
@@ -241,10 +235,7 @@ func (fb *flowBuilder) addIfStatement(s *ast.IfStmt) model.ID {
 				if lastThenID == "" {
 					// First statement in THEN - connect from split going down with "true" case
 					flow := newDownwardFlowWithCase(splitID, actID, "true")
-					applyUserAnchors(flow, trueBranchAnchor, trueBranchAnchor)
-					if thisAnchor != nil && thisAnchor.To != ast.AnchorSideUnset {
-						flow.DestinationConnectionIndex = int(thisAnchor.To)
-					}
+					applyUserAnchors(flow, trueBranchAnchor, branchDestinationAnchor(trueBranchAnchor, thisAnchor))
 					fb.flows = append(fb.flows, flow)
 				} else {
 					flow := newHorizontalFlow(lastThenID, actID)

mdl/executor/cmd_microflows_builder_flows.go

@@ -191,6 +191,20 @@ func applyUserAnchors(flow *microflows.SequenceFlow, origin *ast.FlowAnchors, de
 	}
 }
 
+func branchDestinationAnchor(branchAnchor, stmtAnchor *ast.FlowAnchors) *ast.FlowAnchors {
+	if stmtAnchor != nil && stmtAnchor.To != ast.AnchorSideUnset {
+		return stmtAnchor
+	}
+	return branchAnchor
+}
+
+func pendingFlowAnchors(previousAnchor, pendingAnchor, stmtAnchor *ast.FlowAnchors) (*ast.FlowAnchors, *ast.FlowAnchors) {
+	if pendingAnchor == nil {
+		return previousAnchor, stmtAnchor
+	}
+	return pendingAnchor, branchDestinationAnchor(pendingAnchor, stmtAnchor)
+}
+
 // lastStmtIsReturn reports whether execution of a body is guaranteed to terminate
 // (via RETURN or RAISE ERROR) on every path — i.e. control can never fall off the
 // end of the body into the parent flow.

mdl/executor/cmd_microflows_builder_graph.go

@@ -88,15 +88,8 @@ func (fb *flowBuilder) buildFlowGraph(stmts []ast.MicroflowStatement, returns *a
 			// both From (origin side on the split) and To (the side of the
 			// continuing activity), unless the incoming statement explicitly
 			// overrides its own To.
-			originAnchor := fb.previousStmtAnchor
-			destAnchor := stmtAnchor
-			if pendingFlowAnchor != nil {
-				originAnchor = pendingFlowAnchor
-				if destAnchor == nil || destAnchor.To == ast.AnchorSideUnset {
-					destAnchor = pendingFlowAnchor
-				}
-				pendingFlowAnchor = nil
-			}
+			originAnchor, destAnchor := pendingFlowAnchors(fb.previousStmtAnchor, pendingFlowAnchor, stmtAnchor)
+			pendingFlowAnchor = nil
 			applyUserAnchors(flow, originAnchor, destAnchor)
 			fb.flows = append(fb.flows, flow)
 			fb.previousStmtAnchor = stmtAnchor