Move smart and dumb terminals into separate implementations
Support for smart and dumb terminals are implemented in writer.go,
which makes dumb terminals much more complicated than necessary.
Move smart and dumb terminals into two separate implementations
of StatusOutput, with common code moved into a shared formatter
class.
Test: not yet
Change-Id: I59bbdae479f138b46cd0f03092720a3303e8f0fe
diff --git a/ui/terminal/writer.go b/ui/terminal/writer.go
index ebe4b2a..26e0e34 100644
--- a/ui/terminal/writer.go
+++ b/ui/terminal/writer.go
@@ -21,8 +21,6 @@
"fmt"
"io"
"os"
- "strings"
- "sync"
)
// Writer provides an interface to write temporary and permanent messages to
@@ -39,22 +37,6 @@
// On a dumb terminal, the status messages will be kept.
Print(str string)
- // Status prints the first line of the string to the terminal,
- // overwriting any previous status line. Strings longer than the width
- // of the terminal will be cut off.
- //
- // On a dumb terminal, previous status messages will remain, and the
- // entire first line of the string will be printed.
- StatusLine(str string)
-
- // StatusAndMessage prints the first line of status to the terminal,
- // similarly to StatusLine(), then prints the full msg below that. The
- // status line is retained.
- //
- // There is guaranteed to be no other output in between the status and
- // message.
- StatusAndMessage(status, msg string)
-
// Finish ensures that the output ends with a newline (preserving any
// current status line that is current displayed).
//
@@ -69,6 +51,7 @@
Write(p []byte) (n int, err error)
isSmartTerminal() bool
+ termWidth() (int, bool)
}
// NewWriter creates a new Writer based on the stdio and the TERM
@@ -76,124 +59,34 @@
func NewWriter(stdio StdioInterface) Writer {
w := &writerImpl{
stdio: stdio,
-
- haveBlankLine: true,
}
- if term, ok := os.LookupEnv("TERM"); ok && term != "dumb" {
- w.smartTerminal = isTerminal(stdio.Stdout())
- }
- w.stripEscapes = !w.smartTerminal
-
return w
}
type writerImpl struct {
stdio StdioInterface
-
- haveBlankLine bool
-
- // Protecting the above, we assume that smartTerminal and stripEscapes
- // does not change after initial setup.
- lock sync.Mutex
-
- smartTerminal bool
- stripEscapes bool
-}
-
-func (w *writerImpl) isSmartTerminal() bool {
- return w.smartTerminal
-}
-
-func (w *writerImpl) requestLine() {
- if !w.haveBlankLine {
- fmt.Fprintln(w.stdio.Stdout())
- w.haveBlankLine = true
- }
}
func (w *writerImpl) Print(str string) {
- if w.stripEscapes {
- str = string(stripAnsiEscapes([]byte(str)))
- }
-
- w.lock.Lock()
- defer w.lock.Unlock()
- w.print(str)
-}
-
-func (w *writerImpl) print(str string) {
- if !w.haveBlankLine {
- fmt.Fprint(w.stdio.Stdout(), "\r", "\x1b[K")
- w.haveBlankLine = true
- }
fmt.Fprint(w.stdio.Stdout(), str)
if len(str) == 0 || str[len(str)-1] != '\n' {
fmt.Fprint(w.stdio.Stdout(), "\n")
}
}
-func (w *writerImpl) StatusLine(str string) {
- w.lock.Lock()
- defer w.lock.Unlock()
-
- w.statusLine(str)
-}
-
-func (w *writerImpl) statusLine(str string) {
- if !w.smartTerminal {
- fmt.Fprintln(w.stdio.Stdout(), str)
- return
- }
-
- idx := strings.IndexRune(str, '\n')
- if idx != -1 {
- str = str[0:idx]
- }
-
- // Limit line width to the terminal width, otherwise we'll wrap onto
- // another line and we won't delete the previous line.
- //
- // Run this on every line in case the window has been resized while
- // we're printing. This could be optimized to only re-run when we get
- // SIGWINCH if it ever becomes too time consuming.
- if max, ok := termWidth(w.stdio.Stdout()); ok {
- if len(str) > max {
- // TODO: Just do a max. Ninja elides the middle, but that's
- // more complicated and these lines aren't that important.
- str = str[:max]
- }
- }
-
- // Move to the beginning on the line, print the output, then clear
- // the rest of the line.
- fmt.Fprint(w.stdio.Stdout(), "\r", str, "\x1b[K")
- w.haveBlankLine = false
-}
-
-func (w *writerImpl) StatusAndMessage(status, msg string) {
- if w.stripEscapes {
- msg = string(stripAnsiEscapes([]byte(msg)))
- }
-
- w.lock.Lock()
- defer w.lock.Unlock()
-
- w.statusLine(status)
- w.requestLine()
- w.print(msg)
-}
-
-func (w *writerImpl) Finish() {
- w.lock.Lock()
- defer w.lock.Unlock()
-
- w.requestLine()
-}
+func (w *writerImpl) Finish() {}
func (w *writerImpl) Write(p []byte) (n int, err error) {
- w.Print(string(p))
- return len(p), nil
+ return w.stdio.Stdout().Write(p)
+}
+
+func (w *writerImpl) isSmartTerminal() bool {
+ return isSmartTerminal(w.stdio.Stdout())
+}
+
+func (w *writerImpl) termWidth() (int, bool) {
+ return termWidth(w.stdio.Stdout())
}
// StdioInterface represents a set of stdin/stdout/stderr Reader/Writers