diff options
Diffstat (limited to 'Godeps/_workspace/src/gopkg.in/check.v1/printer.go')
-rw-r--r-- | Godeps/_workspace/src/gopkg.in/check.v1/printer.go | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/gopkg.in/check.v1/printer.go b/Godeps/_workspace/src/gopkg.in/check.v1/printer.go new file mode 100644 index 000000000..e0f7557b5 --- /dev/null +++ b/Godeps/_workspace/src/gopkg.in/check.v1/printer.go @@ -0,0 +1,168 @@ +package check + +import ( + "bytes" + "go/ast" + "go/parser" + "go/printer" + "go/token" + "os" +) + +func indent(s, with string) (r string) { + eol := true + for i := 0; i != len(s); i++ { + c := s[i] + switch { + case eol && c == '\n' || c == '\r': + case c == '\n' || c == '\r': + eol = true + case eol: + eol = false + s = s[:i] + with + s[i:] + i += len(with) + } + } + return s +} + +func printLine(filename string, line int) (string, error) { + fset := token.NewFileSet() + file, err := os.Open(filename) + if err != nil { + return "", err + } + fnode, err := parser.ParseFile(fset, filename, file, parser.ParseComments) + if err != nil { + return "", err + } + config := &printer.Config{Mode: printer.UseSpaces, Tabwidth: 4} + lp := &linePrinter{fset: fset, fnode: fnode, line: line, config: config} + ast.Walk(lp, fnode) + result := lp.output.Bytes() + // Comments leave \n at the end. + n := len(result) + for n > 0 && result[n-1] == '\n' { + n-- + } + return string(result[:n]), nil +} + +type linePrinter struct { + config *printer.Config + fset *token.FileSet + fnode *ast.File + line int + output bytes.Buffer + stmt ast.Stmt +} + +func (lp *linePrinter) emit() bool { + if lp.stmt != nil { + lp.trim(lp.stmt) + lp.printWithComments(lp.stmt) + lp.stmt = nil + return true + } + return false +} + +func (lp *linePrinter) printWithComments(n ast.Node) { + nfirst := lp.fset.Position(n.Pos()).Line + nlast := lp.fset.Position(n.End()).Line + for _, g := range lp.fnode.Comments { + cfirst := lp.fset.Position(g.Pos()).Line + clast := lp.fset.Position(g.End()).Line + if clast == nfirst-1 && lp.fset.Position(n.Pos()).Column == lp.fset.Position(g.Pos()).Column { + for _, c := range g.List { + lp.output.WriteString(c.Text) + lp.output.WriteByte('\n') + } + } + if cfirst >= nfirst && cfirst <= nlast && n.End() <= g.List[0].Slash { + // The printer will not include the comment if it starts past + // the node itself. Trick it into printing by overlapping the + // slash with the end of the statement. + g.List[0].Slash = n.End() - 1 + } + } + node := &printer.CommentedNode{n, lp.fnode.Comments} + lp.config.Fprint(&lp.output, lp.fset, node) +} + +func (lp *linePrinter) Visit(n ast.Node) (w ast.Visitor) { + if n == nil { + if lp.output.Len() == 0 { + lp.emit() + } + return nil + } + first := lp.fset.Position(n.Pos()).Line + last := lp.fset.Position(n.End()).Line + if first <= lp.line && last >= lp.line { + // Print the innermost statement containing the line. + if stmt, ok := n.(ast.Stmt); ok { + if _, ok := n.(*ast.BlockStmt); !ok { + lp.stmt = stmt + } + } + if first == lp.line && lp.emit() { + return nil + } + return lp + } + return nil +} + +func (lp *linePrinter) trim(n ast.Node) bool { + stmt, ok := n.(ast.Stmt) + if !ok { + return true + } + line := lp.fset.Position(n.Pos()).Line + if line != lp.line { + return false + } + switch stmt := stmt.(type) { + case *ast.IfStmt: + stmt.Body = lp.trimBlock(stmt.Body) + case *ast.SwitchStmt: + stmt.Body = lp.trimBlock(stmt.Body) + case *ast.TypeSwitchStmt: + stmt.Body = lp.trimBlock(stmt.Body) + case *ast.CaseClause: + stmt.Body = lp.trimList(stmt.Body) + case *ast.CommClause: + stmt.Body = lp.trimList(stmt.Body) + case *ast.BlockStmt: + stmt.List = lp.trimList(stmt.List) + } + return true +} + +func (lp *linePrinter) trimBlock(stmt *ast.BlockStmt) *ast.BlockStmt { + if !lp.trim(stmt) { + return lp.emptyBlock(stmt) + } + stmt.Rbrace = stmt.Lbrace + return stmt +} + +func (lp *linePrinter) trimList(stmts []ast.Stmt) []ast.Stmt { + for i := 0; i != len(stmts); i++ { + if !lp.trim(stmts[i]) { + stmts[i] = lp.emptyStmt(stmts[i]) + break + } + } + return stmts +} + +func (lp *linePrinter) emptyStmt(n ast.Node) *ast.ExprStmt { + return &ast.ExprStmt{&ast.Ellipsis{n.Pos(), nil}} +} + +func (lp *linePrinter) emptyBlock(n ast.Node) *ast.BlockStmt { + p := n.Pos() + return &ast.BlockStmt{p, []ast.Stmt{lp.emptyStmt(n)}, p} +} |