go/parser.ParseFiles: don't override error (to nil) if there is one

Also: Return first instead of last error as that seems more useful.

R=r
CC=golang-dev
https://golang.org/cl/1897050

diff --git a/src/pkg/go/parser/interface.go b/src/pkg/go/parser/interface.go
index e1ddb37c3046ce719d63b5b45c5f198edfe48933..6d11a266692616b77c25ca1d64402a200c129caf 100644 (file)
--- a/src/pkg/go/parser/interface.go
+++ b/src/pkg/go/parser/interface.go
@@ -147,16 +147,13 @@ func ParseFile(filename string, src interface{}, scope *ast.Scope, mode uint) (*
 // bits are passed to ParseFile unchanged.
 //
 // Files with parse errors are ignored. In this case the map of packages may
-// be incomplete (missing packages and/or incomplete packages) and the last
+// be incomplete (missing packages and/or incomplete packages) and the first
 // error encountered is returned.
 //
-func ParseFiles(filenames []string, scope *ast.Scope, mode uint) (map[string]*ast.Package, os.Error) {
-       pkgs := make(map[string]*ast.Package)
-       var err os.Error
+func ParseFiles(filenames []string, scope *ast.Scope, mode uint) (pkgs map[string]*ast.Package, first os.Error) {
+       pkgs = make(map[string]*ast.Package)
        for _, filename := range filenames {
-               var src *ast.File
-               src, err = ParseFile(filename, nil, scope, mode)
-               if err == nil {
+               if src, err := ParseFile(filename, nil, scope, mode); err == nil {
                        name := src.Name.Name()
                        pkg, found := pkgs[name]
                        if !found {
@@ -164,10 +161,11 @@ func ParseFiles(filenames []string, scope *ast.Scope, mode uint) (map[string]*as
                                pkgs[name] = pkg
                        }
                        pkg.Files[filename] = src
+               } else if first == nil {
+                       first = err
                }
        }
-
-       return pkgs, err
+       return
 }