Fixed bug in which commands could not be assigned to pipeline results

ucl/ast.go

@@ -105,8 +105,7 @@ type astDot struct {
 type astCmd struct {
 	Pos        lexer.Position
 	Name       astDot   `parser:"@@"`
-	Assign     *astDot  `parser:"( EQ @@"`
+	InvokeArgs []astDot `parser:"@@*"`
-	InvokeArgs []astDot `parser:" | @@+ )?"`
 }
 
 type astPipeline struct {
@@ -114,9 +113,15 @@ type astPipeline struct {
 	Rest  []*astCmd `parser:"( PIPE @@ )*"`
 }
 
+type astAssignOrPipeline struct {
+	First    *astCmd      `parser:"@@"`
+	Assign   *astPipeline `parser:"( EQ @@ "`
+	Pipeline []*astCmd    `parser:"| ( PIPE @@ )+ )?"`
+}
+
 type astStatements struct {
-	First *astPipeline   `parser:"@@"`
+	First *astAssignOrPipeline   `parser:"@@"`
-	Rest  []*astPipeline `parser:"( NL+ @@ )*"` // TODO: also add support for newlines
+	Rest  []*astAssignOrPipeline `parser:"( NL+ @@ )*"` // TODO: also add support for newlines
 }
 
 type astScript struct {

ucl/eval.go

@@ -32,7 +32,7 @@ func (e evaluator) evalStatement(ctx context.Context, ec *evalCtx, n *astStateme
 		return nil, nil
 	}
 
-	res, err := e.evalPipeline(ctx, ec, n.First)
+	res, err := e.evalAssignOrPipeline(ctx, ec, n.First)
 	if err != nil {
 		return nil, err
 	}
@@ -41,7 +41,7 @@ func (e evaluator) evalStatement(ctx context.Context, ec *evalCtx, n *astStateme
 	}
 
 	for _, rest := range n.Rest {
-		out, err := e.evalPipeline(ctx, ec, rest)
+		out, err := e.evalAssignOrPipeline(ctx, ec, rest)
 		if err != nil {
 			return nil, err
 		}
@@ -50,6 +50,36 @@ func (e evaluator) evalStatement(ctx context.Context, ec *evalCtx, n *astStateme
 	return res, nil
 }
 
+func (e evaluator) evalAssignOrPipeline(ctx context.Context, ec *evalCtx, n *astAssignOrPipeline) (Object, error) {
+	switch {
+	case n.Assign != nil:
+		// Assignment
+		assignVal, err := e.evalPipeline(ctx, ec, n.Assign)
+		if err != nil {
+			return nil, err
+		}
+
+		return e.assignCmd(ctx, ec, n.First, assignVal)
+	case len(n.Pipeline) > 0:
+		res, err := e.evalCmd(ctx, ec, nil, n.First)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, rest := range n.Pipeline {
+			out, err := e.evalCmd(ctx, ec, res, rest)
+			if err != nil {
+				return nil, err
+			}
+			res = out
+		}
+		return res, nil
+
+	}
+
+	return e.evalCmd(ctx, ec, nil, n.First)
+}
+
 func (e evaluator) evalPipeline(ctx context.Context, ec *evalCtx, n *astPipeline) (Object, error) {
 	res, err := e.evalCmd(ctx, ec, nil, n.First)
 	if err != nil {
@@ -72,14 +102,6 @@ func (e evaluator) evalPipeline(ctx context.Context, ec *evalCtx, n *astPipeline
 
 func (e evaluator) evalCmd(ctx context.Context, ec *evalCtx, currentPipe Object, ast *astCmd) (Object, error) {
 	switch {
-	case ast.Assign != nil:
-		// Assignment
-		assignVal, err := e.evalDot(ctx, ec, *ast.Assign)
-		if err != nil {
-			return nil, err
-		}
-
-		return e.assignDot(ctx, ec, ast.Name, assignVal)
 	case (ast.Name.Arg.Ident != nil) && len(ast.Name.DotSuffix) == 0:
 		name := ast.Name.Arg.Ident.String()
 
@@ -114,6 +136,13 @@ func (e evaluator) evalCmd(ctx context.Context, ec *evalCtx, currentPipe Object,
 	return nameElem, nil
 }
 
+func (e evaluator) assignCmd(ctx context.Context, ec *evalCtx, ast *astCmd, toVal Object) (Object, error) {
+	if len(ast.InvokeArgs) != 0 {
+		return nil, errors.New("cannot assign to multiple values")
+	}
+	return e.assignDot(ctx, ec, ast.Name, toVal)
+}
+
 func (e evaluator) evalInvokable(ctx context.Context, ec *evalCtx, currentPipe Object, ast *astCmd, cmd invokable) (Object, error) {
 	var (
 		pargs   ListObject