add noAlt option. fix list shrinking.

README.md

@@ -180,6 +180,10 @@ The screen on which every other node renders.
 - **tabSize** - the width of tabs within an element's content.
 - **autoPadding** - automatically position child elements with border and
   padding in mind.
+- **noAlt** - do not clear the screen, only scroll down enough to make room for
+  the elements on the screen. do not use the alternate screenbuffer. useful for
+  writing a CLI tool or some kind of prompt (experimental - see
+  test/widget-noalt.js).
 - **log** - create a log file. see `log` method.
 - **dump** - dump all output and input to desired file. can be used together
   with `log` option if set as a boolean.

lib/program.js

@@ -2453,7 +2453,29 @@ Program.prototype.deviceStatus = function(param, callback, dec) {
 };
 
 Program.prototype.getCursor = function(callback) {
-  return this.deviceStatus('6', callback);
+  return this.deviceStatus(6, callback);
+};
+
+Program.prototype.saveReportedCursor = function(callback) {
+  var self = this;
+  if (this.tput.strings.user7 === '\x1b[6n' || this.term('screen')) {
+    return this.getCursor(function(err, data) {
+      if (data) {
+        self._rx = data.status.x;
+        self._ry = data.status.y;
+      }
+      if (!callback) return;
+      return callback(err);
+    });
+  }
+  if (!callback) return;
+  return callback();
+};
+
+Program.prototype.restoreReportedCursor = function() {
+  if (this._rx == null) return;
+  return this.cup(this._ry, this._rx);
+  // return this.nel();
 };
 
 /**
@@ -3531,7 +3553,7 @@ Program.prototype.manipulateWindow = function() {
 };
 
 Program.prototype.getWindowSize = function(callback) {
-  return this.manipulateWindow('18', callback);
+  return this.manipulateWindow(18, callback);
 };
 
 // CSI Pt; Pl; Pb; Pr; Ps$ t

lib/widget.js

@@ -423,6 +423,22 @@ Screen.prototype.__defineSetter__('title', function(title) {
 });
 
 Screen.prototype.enter = function() {
+  if (this.options.noAlt) {
+    if (this._entered) return;
+    this._entered = true;
+    var self = this;
+    this.program.saveReportedCursor();
+    this.program.hideCursor();
+    this.program.cup(0, 0);
+    this.program.csr(0, this.height - 1);
+    this.alloc();
+    var log = console.log;
+    console.log = function() {
+      self.leave();
+      return log.apply(console, arguments);
+    };
+    return;
+  }
   if (this.program.isAlt) return;
   this.program.alternateBuffer();
   this.program.hideCursor();
@@ -432,6 +448,22 @@ Screen.prototype.enter = function() {
 };
 
 Screen.prototype.leave = function() {
+  if (this.options.noAlt) {
+    if (this._left) return;
+    this._left = true;
+    if (this.program.scrollTop !== 0
+        || this.program.scrollBottom !== this.rows - 1) {
+      this.program.csr(0, this.height - 1);
+    }
+    this.program.restoreReportedCursor();
+    this.program.nel();
+    this.program.showCursor();
+    if (this._listenedMouse) {
+      this.program.disableMouse();
+    }
+    this.program.flush();
+    return;
+  }
   if (!this.program.isAlt) return;
   if (this.program.scrollTop !== 0
       || this.program.scrollBottom !== this.rows - 1) {
@@ -636,6 +668,27 @@ Screen.prototype.alloc = function() {
     }
   }
 
+  if (this.options.noAlt) {
+    var self = this;
+    var draw = self.draw;
+    this.draw = function() {};
+    return this.once('render', function() {
+      var top = -1;
+      self.forDescendants(function(el) {
+        if (!el.lpos) return;
+        if (top === -1 || el.lpos.yi < top) {
+          top = el.lpos.yi;
+        }
+      });
+      self.draw = draw;
+      if (top !== -1) {
+        top = self.program.rows - top;
+        self.program.output.write(Array(top + 1).join('\n'));
+      }
+      self.render();
+    });
+  }
+
   this.program.clear();
 };
 
@@ -3057,7 +3110,14 @@ Element.prototype._getShrinkBox = function(xi, xl, yi, yl, get) {
   if (this.position.height == null
       && (this.position.top == null
       || this.position.bottom == null)
-      && !this.scrollable) {
+      && (!this.scrollable || this._isList)) {
+    // NOTE: Lists get special treatment if they are shrunken - assume they
+    // want all list items showing. This is one case we can calculate the
+    // height based on items/boxes.
+    if (this._isList) {
+      myi = 0 - this.itop;
+      myl = this.items.length + this.ibottom;
+    }
     if (this.position.top == null && this.position.bottom != null) {
       yi = yl - (myl - myi);
       if (!this.screen.autoPadding) {
@@ -3097,7 +3157,8 @@ Element.prototype._getShrinkContent = function(xi, xl, yi, yl, get) {
   if (this.position.height == null
       && (this.position.top == null
       || this.position.bottom == null)
-      && !this.scrollable) {
+      // && !this.scrollable) {
+      && (!this.scrollable || this._isList)) {
     if (this.position.top == null && this.position.bottom != null) {
       yi = yl - h - this.iheight;
     } else {

test/widget-noalt.js

@@ -0,0 +1,48 @@
+var blessed = require('../')
+  , screen;
+
+screen = blessed.screen({
+  dump: __dirname + '/logs/noalt.log',
+  title: 'widget-noalt test',
+  noAlt: true
+});
+
+var list = blessed.list({
+  parent: screen,
+  align: 'center',
+  mouse: true,
+  keys: true,
+  vi: true,
+  width: '50%',
+  height: 'shrink',
+  //border: 'line',
+  bottom: 2,
+  left: 0,
+  style: {
+    fg: 'blue',
+    bg: 'default',
+    selected: {
+      bg: 'green'
+    }
+  },
+  items: [
+    'one',
+    'two',
+    'three'
+  ]
+});
+
+list.select(0);
+
+list.on('select', function(item) {
+  console.log(item.getText());
+  process.exit(0);
+});
+
+screen.key('C-c', function() {
+  process.exit(0);
+});
+
+list.focus();
+
+screen.render();