fix: externalised constants (#760)

There was a bug related to externalised constants when producing a report for a constraint failure.  It was just a missing case for `LabelledConstant`.

Author: DavePearce

pkg/cmd/debug.go

@@ -110,7 +110,7 @@ func init() {
 	debugCmd.Flags().Bool("mir", false, "Print constraints at MIR level")
 	debugCmd.Flags().Bool("stats", false, "Print summary information")
 	debugCmd.Flags().Bool("spillage", false, "Print spillage information")
-	debugCmd.Flags().StringArrayP("set", "s", []string{}, "set value of externalised constant.")
+	debugCmd.Flags().StringArrayP("set", "S", []string{}, "set value of externalised constant.")
 }
 
 func printSchemas(hirSchema *hir.Schema, hir bool, mir bool, air bool, optConfig mir.OptimisationConfig) {

pkg/hir/context.go

@@ -85,6 +85,8 @@ func requiredColumnsOfTerm(e Term) *set.SortedSet[uint] {
 		return set.NewSortedSet[uint]()
 	case *ColumnAccess:
 		return requiredColumnsOfColumnAccess(e)
+	case *LabelledConstant:
+		return set.NewSortedSet[uint]()
 	case *Exp:
 		return requiredColumnsOfTerm(e.Arg)
 	case *IfZero:
@@ -138,6 +140,8 @@ func requiredCellsOfTerm(e Term, row int, tr trace.Trace) *set.AnySortedSet[trac
 		return set.NewAnySortedSet[trace.CellRef]()
 	case *ColumnAccess:
 		return requiredCellsOfColumnAccess(e, row)
+	case *LabelledConstant:
+		return set.NewAnySortedSet[trace.CellRef]()
 	case *Exp:
 		return requiredCellsOfTerm(e.Arg, row, tr)
 	case *IfZero:

pkg/hir/substitute.go

@@ -23,21 +23,21 @@ import (
 func substituteConstraint(mapping map[string]fr.Element, constraint sc.Constraint) {
 	switch e := constraint.(type) {
 	case LookupConstraint:
-		// Subistute through source expressions
+		// Substitute through source expressions
 		for _, source := range e.Sources {
 			substituteExpression(mapping, source.Expr)
 		}
-		// Subistute through target expressions
-		for _, source := range e.Targets {
-			substituteExpression(mapping, source.Expr)
+		// Substitute through target expressions
+		for _, target := range e.Targets {
+			substituteExpression(mapping, target.Expr)
 		}
 	case RangeConstraint:
 		substituteExpression(mapping, e.Expr.Expr)
 	case SortedConstraint:
 		if e.Selector.HasValue() {
 			substituteExpression(mapping, e.Selector.Unwrap().Expr)
 		}
-		// Subistute through source expressions
+		// Substitute through source expressions
 		for _, source := range e.Sources {
 			substituteExpression(mapping, source.Expr)
 		}