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author | Felix Lange <fjl@twurst.com> | 2015-03-06 17:39:31 +0800 |
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committer | Felix Lange <fjl@twurst.com> | 2015-03-06 17:39:31 +0800 |
commit | 2393de5d6b535a850e8b5d510aa2ae4f940f3d23 (patch) | |
tree | 020fdbfeb9046f101b7e2ccab31bfc3c02caf1aa /Godeps/_workspace/src/github.com/peterh/liner/common.go | |
parent | 38f6d60e6e699db24b7a850b5999823b9e36d5bb (diff) | |
download | go-tangerine-2393de5d6b535a850e8b5d510aa2ae4f940f3d23.tar.gz go-tangerine-2393de5d6b535a850e8b5d510aa2ae4f940f3d23.tar.zst go-tangerine-2393de5d6b535a850e8b5d510aa2ae4f940f3d23.zip |
Godeps: add github.com/peterh/liner
Diffstat (limited to 'Godeps/_workspace/src/github.com/peterh/liner/common.go')
-rw-r--r-- | Godeps/_workspace/src/github.com/peterh/liner/common.go | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/peterh/liner/common.go b/Godeps/_workspace/src/github.com/peterh/liner/common.go new file mode 100644 index 000000000..f8753a195 --- /dev/null +++ b/Godeps/_workspace/src/github.com/peterh/liner/common.go @@ -0,0 +1,219 @@ +/* +Package liner implements a simple command line editor, inspired by linenoise +(https://github.com/antirez/linenoise/). This package supports WIN32 in +addition to the xterm codes supported by everything else. +*/ +package liner + +import ( + "bufio" + "bytes" + "container/ring" + "errors" + "fmt" + "io" + "strings" + "sync" + "unicode/utf8" +) + +type commonState struct { + terminalSupported bool + outputRedirected bool + inputRedirected bool + history []string + historyMutex sync.RWMutex + completer WordCompleter + columns int + killRing *ring.Ring + ctrlCAborts bool + r *bufio.Reader + tabStyle TabStyle +} + +// TabStyle is used to select how tab completions are displayed. +type TabStyle int + +// Two tab styles are currently available: +// +// TabCircular cycles through each completion item and displays it directly on +// the prompt +// +// TabPrints prints the list of completion items to the screen after a second +// tab key is pressed. This behaves similar to GNU readline and BASH (which +// uses readline) +const ( + TabCircular TabStyle = iota + TabPrints +) + +// ErrPromptAborted is returned from Prompt or PasswordPrompt when the user presses Ctrl-C +// if SetCtrlCAborts(true) has been called on the State +var ErrPromptAborted = errors.New("prompt aborted") + +// ErrNotTerminalOutput is returned from Prompt or PasswordPrompt if the +// platform is normally supported, but stdout has been redirected +var ErrNotTerminalOutput = errors.New("standard output is not a terminal") + +// Max elements to save on the killring +const KillRingMax = 60 + +// HistoryLimit is the maximum number of entries saved in the scrollback history. +const HistoryLimit = 1000 + +// ReadHistory reads scrollback history from r. Returns the number of lines +// read, and any read error (except io.EOF). +func (s *State) ReadHistory(r io.Reader) (num int, err error) { + s.historyMutex.Lock() + defer s.historyMutex.Unlock() + + in := bufio.NewReader(r) + num = 0 + for { + line, part, err := in.ReadLine() + if err == io.EOF { + break + } + if err != nil { + return num, err + } + if part { + return num, fmt.Errorf("line %d is too long", num+1) + } + if !utf8.Valid(line) { + return num, fmt.Errorf("invalid string at line %d", num+1) + } + num++ + s.history = append(s.history, string(line)) + if len(s.history) > HistoryLimit { + s.history = s.history[1:] + } + } + return num, nil +} + +// WriteHistory writes scrollback history to w. Returns the number of lines +// successfully written, and any write error. +// +// Unlike the rest of liner's API, WriteHistory is safe to call +// from another goroutine while Prompt is in progress. +// This exception is to facilitate the saving of the history buffer +// during an unexpected exit (for example, due to Ctrl-C being invoked) +func (s *State) WriteHistory(w io.Writer) (num int, err error) { + s.historyMutex.RLock() + defer s.historyMutex.RUnlock() + + for _, item := range s.history { + _, err := fmt.Fprintln(w, item) + if err != nil { + return num, err + } + num++ + } + return num, nil +} + +// AppendHistory appends an entry to the scrollback history. AppendHistory +// should be called iff Prompt returns a valid command. +func (s *State) AppendHistory(item string) { + s.historyMutex.Lock() + defer s.historyMutex.Unlock() + + if len(s.history) > 0 { + if item == s.history[len(s.history)-1] { + return + } + } + s.history = append(s.history, item) + if len(s.history) > HistoryLimit { + s.history = s.history[1:] + } +} + +// Returns the history lines starting with prefix +func (s *State) getHistoryByPrefix(prefix string) (ph []string) { + for _, h := range s.history { + if strings.HasPrefix(h, prefix) { + ph = append(ph, h) + } + } + return +} + +// Returns the history lines matching the inteligent search +func (s *State) getHistoryByPattern(pattern string) (ph []string, pos []int) { + if pattern == "" { + return + } + for _, h := range s.history { + if i := strings.Index(h, pattern); i >= 0 { + ph = append(ph, h) + pos = append(pos, i) + } + } + return +} + +// Completer takes the currently edited line content at the left of the cursor +// and returns a list of completion candidates. +// If the line is "Hello, wo!!!" and the cursor is before the first '!', "Hello, wo" is passed +// to the completer which may return {"Hello, world", "Hello, Word"} to have "Hello, world!!!". +type Completer func(line string) []string + +// WordCompleter takes the currently edited line with the cursor position and +// returns the completion candidates for the partial word to be completed. +// If the line is "Hello, wo!!!" and the cursor is before the first '!', ("Hello, wo!!!", 9) is passed +// to the completer which may returns ("Hello, ", {"world", "Word"}, "!!!") to have "Hello, world!!!". +type WordCompleter func(line string, pos int) (head string, completions []string, tail string) + +// SetCompleter sets the completion function that Liner will call to +// fetch completion candidates when the user presses tab. +func (s *State) SetCompleter(f Completer) { + if f == nil { + s.completer = nil + return + } + s.completer = func(line string, pos int) (string, []string, string) { + return "", f(line[:pos]), line[pos:] + } +} + +// SetWordCompleter sets the completion function that Liner will call to +// fetch completion candidates when the user presses tab. +func (s *State) SetWordCompleter(f WordCompleter) { + s.completer = f +} + +// SetTabCompletionStyle sets the behvavior when the Tab key is pressed +// for auto-completion. TabCircular is the default behavior and cycles +// through the list of candidates at the prompt. TabPrints will print +// the available completion candidates to the screen similar to BASH +// and GNU Readline +func (s *State) SetTabCompletionStyle(tabStyle TabStyle) { + s.tabStyle = tabStyle +} + +// ModeApplier is the interface that wraps a representation of the terminal +// mode. ApplyMode sets the terminal to this mode. +type ModeApplier interface { + ApplyMode() error +} + +// SetCtrlCAborts sets whether Prompt on a supported terminal will return an +// ErrPromptAborted when Ctrl-C is pressed. The default is false (will not +// return when Ctrl-C is pressed). Unsupported terminals typically raise SIGINT +// (and Prompt does not return) regardless of the value passed to SetCtrlCAborts. +func (s *State) SetCtrlCAborts(aborts bool) { + s.ctrlCAborts = aborts +} + +func (s *State) promptUnsupported(p string) (string, error) { + if !s.inputRedirected { + fmt.Print(p) + } + linebuf, _, err := s.r.ReadLine() + if err != nil { + return "", err + } + return string(bytes.TrimSpace(linebuf)), nil +} |