[PATCH 2 of 2 PROPOSAL] progress: simplistic implementation of nested progress meters

[timeless]

# HG changeset patch
# User timeless <timeless at gmail.com>
# Date 1287450864 -10800
# Node ID 7fbbfd07c689f6eefac3abd50a902730c5798b67
# Parent  6122cc35c005921edae764a85369d432dde39211
progress: simplistic implementation of nested progress meters

diff --git a/hgext/progress.py b/hgext/progress.py
--- a/hgext/progress.py
+++ b/hgext/progress.py
@@ -27,6 +27,8 @@ The following settings are available::
 
   [progress]
   delay = 3 # number of seconds (float) before showing the progress bar
+  nestdelay = 20 # number of seconds (float) before showing a progress
+                 # bar after popping a progress indicator
   refresh = 0.1 # time in seconds between refreshes of the progress bar
   format = topic bar number # format of the progress bar
   width = <none> # if set, the maximum width of the progress information
@@ -58,9 +60,29 @@ class progbar(object):
     def __init__(self, ui):
         self.ui = ui
         self.resetstate()
+        self.saved = []
 
-    def resetstate(self):
-        self.topics = []
+    def resetstate(self, topic = None):
+        if topic:
+            index = self.topics.index(topic)
+            del self.saved[index]
+            del self.topics[index]
+        else:
+            self.topics = []
+
+        if len(self.topics) > 0:
+            index = len(self.topics) - 1
+            topic = self.topics[index]
+            saved = self.saved[index]
+            if saved:
+                self.printed = True
+                now = time.time()
+                self.lastprint = now
+                self.refresh = float(self.ui.config(
+                   'progress', 'nestdelay', default=20))
+                self.show(topic, saved.pos, saved.item, saved.unit, saved.total)
+            return
+
         self.printed = False
         self.lastprint = time.time() + float(self.ui.config(
             'progress', 'delay', default=3))
@@ -71,6 +93,13 @@ class progbar(object):
             'progress', 'format',
             default=['topic', 'bar', 'number'])
 
+    def save(self, topic, pos, item, unit, total):
+        self.saved[self.topics.index(topic)] = {
+            pos: pos,
+            item: item,
+            unit: unit,
+            total: total}
+
     def show(self, topic, pos, item, unit, total):
         if not shouldprint(self.ui):
             return
@@ -163,15 +192,18 @@ class progbar(object):
         if pos is None:
             if self.topics and self.topics[-1] == topic and self.printed:
                 self.complete()
-                self.resetstate()
+                self.resetstate(topic)
         else:
             if topic not in self.topics:
                 self.topics.append(topic)
+                self.saved.append(None)
             now = time.time()
             if (now - self.lastprint >= self.refresh
                 and topic == self.topics[-1]):
                 self.lastprint = now
                 self.show(topic, pos, item, unit, total)
+            elif topic != self.topics[-1]:
+                self.save(topic, pos, item, unit, total)
 
 def uisetup(ui):
     class progressui(ui.__class__):