完善 wago 方法解析

internal/app/app_wasm_.go

@@ -3,6 +3,8 @@
 package app
 
 import (
+	"fmt"
+	"os"
 	"strings"
 
 	"wa-lang.org/wa/internal/backends/compiler_wat"
@@ -10,6 +12,9 @@ import (
 )
 
 func (p *App) WASM(filename string) ([]byte, error) {
+	if _, err := os.Lstat(filename); err != nil {
+		return nil, fmt.Errorf("%q not found", filename)
+	}
 	cfg := p.opt.Config()
 	prog, err := loader.LoadProgram(cfg, filename)
 	if err != nil {

internal/parser/parser.go

@@ -2418,27 +2418,34 @@ func (p *parser) parseFuncDecl() *ast.FuncDecl {
 	scope := ast.NewScope(p.topScope) // function scope
 
 	var recv *ast.FieldList
-	if p.tok == token.LPAREN {
-		recv = p.parseParameters(scope, false)
+	if p.wagoMode {
+		if p.tok == token.LPAREN {
+			recv = p.parseParameters(scope, false)
+		}
 	}
 
 	ident := p.parseIdent()
 
 	// func Type.method()
-	if recv == nil && p.tok == token.PERIOD {
-		thisIdent := &ast.Ident{Name: "this"}
-		thisField := &ast.Field{
-			Names: []*ast.Ident{thisIdent},
-			Type:  &ast.StarExpr{X: ident},
-		}
-		recv = &ast.FieldList{
-			List: []*ast.Field{thisField},
-		}
+	if !p.wagoMode {
+		if recv != nil {
+			panic("unreachable")
+		}
+		if p.tok == token.PERIOD {
+			thisIdent := &ast.Ident{Name: "this"}
+			thisField := &ast.Field{
+				Names: []*ast.Ident{thisIdent},
+				Type:  &ast.StarExpr{X: ident},
+			}
+			recv = &ast.FieldList{
+				List: []*ast.Field{thisField},
+			}
 
-		p.declare(thisField, nil, scope, ast.Var, thisIdent)
+			p.declare(thisField, nil, scope, ast.Var, thisIdent)
 
-		p.next()
-		ident = p.parseIdent()
+			p.next()
+			ident = p.parseIdent()
+		}
 	}
 
 	params, results, arrowPos := p.parseSignature(scope)