diff options
Diffstat (limited to 'libgo/go/go/parser/interface.go')
| -rw-r--r-- | libgo/go/go/parser/interface.go | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/libgo/go/go/parser/interface.go b/libgo/go/go/parser/interface.go index c6fd93240a..724d8658a7 100644 --- a/libgo/go/go/parser/interface.go +++ b/libgo/go/go/parser/interface.go @@ -73,7 +73,7 @@ const ( // // The mode parameter controls the amount of source text parsed and other // optional parser functionality. Position information is recorded in the -// file set fset. +// file set fset, which must not be nil. // // If the source couldn't be read, the returned AST is nil and the error // indicates the specific failure. If the source was read but syntax @@ -82,6 +82,10 @@ const ( // are returned via a scanner.ErrorList which is sorted by file position. // func ParseFile(fset *token.FileSet, filename string, src interface{}, mode Mode) (f *ast.File, err error) { + if fset == nil { + panic("parser.ParseFile: no token.FileSet provided (fset == nil)") + } + // get source text, err := readSource(filename, src) if err != nil { @@ -125,7 +129,8 @@ func ParseFile(fset *token.FileSet, filename string, src interface{}, mode Mode) // // If filter != nil, only the files with os.FileInfo entries passing through // the filter (and ending in ".go") are considered. The mode bits are passed -// to ParseFile unchanged. Position information is recorded in fset. +// to ParseFile unchanged. Position information is recorded in fset, which +// must not be nil. // // If the directory couldn't be read, a nil map and the respective error are // returned. If a parse error occurred, a non-nil but incomplete map and the @@ -168,10 +173,15 @@ func ParseDir(fset *token.FileSet, path string, filter func(os.FileInfo) bool, m } // ParseExprFrom is a convenience function for parsing an expression. -// The arguments have the same meaning as for Parse, but the source must -// be a valid Go (type or value) expression. +// The arguments have the same meaning as for ParseFile, but the source must +// be a valid Go (type or value) expression. Specifically, fset must not +// be nil. // func ParseExprFrom(fset *token.FileSet, filename string, src interface{}, mode Mode) (ast.Expr, error) { + if fset == nil { + panic("parser.ParseExprFrom: no token.FileSet provided (fset == nil)") + } + // get source text, err := readSource(filename, src) if err != nil { |