Merge pull request #487 from con-f-use/master

Show progressbar only if total execution time is noticable

CHANGES

@@ -23,10 +23,10 @@ Version 7.0
 - ``launch`` now works properly under Cygwin. See #650.
 - `CliRunner.invoke` now may receive `args` as a string representing
   a Unix shell command. See #664.
-- Fix bug that caused bashcompletion to give improper completions on 
+- Fix bug that caused bashcompletion to give improper completions on
   chained commands. See #774.
 - Add support for bright colors.
-- 't' and 'f' are now converted to True and False. 
+- 't' and 'f' are now converted to True and False.
 - Fix bug that caused bashcompletion to give improper completions on
   chained commands when a required option/argument was being completed.
   See #790.

click/_termui_impl.py

@@ -90,6 +90,7 @@ def __init__(self, iterable, length=None, fill_char='#', empty_char=' ',
         self.current_item = None
         self.is_hidden = not isatty(self.file)
         self._last_line = None
+        self.short_limit = 0.5
 
     def __enter__(self):
         self.entered = True
@@ -105,8 +106,11 @@ def __iter__(self):
         self.render_progress()
         return self.generator()
 
+    def is_fast(self):
+        return time.time() - self.start <= self.short_limit
+
     def render_finish(self):
-        if self.is_hidden:
+        if self.is_hidden or self.is_fast():
             return
         self.file.write(AFTER_BAR)
         self.file.flush()
@@ -224,7 +228,8 @@ def render_progress(self):
         buf.append(' ' * (clear_width - line_len))
         line = ''.join(buf)
         # Render the line only if it changed.
-        if line != self._last_line:
+
+        if line != self._last_line and not self.is_fast():
             self._last_line = line
             echo(line, file=self.file, color=self.color, nl=True)
             self.file.flush()

tests/test_termui.py

@@ -2,15 +2,28 @@
 import time
 
 
+class FakeClock(object):
+    def __init__(self):
+        self.now = time.time()
+
+    def advance_time(self, seconds=1):
+        self.now += seconds
+
+    def time(self):
+        return self.now
+
+
 def test_progressbar_strip_regression(runner, monkeypatch):
+    fake_clock = FakeClock()
     label = '    padded line'
 
     @click.command()
     def cli():
         with click.progressbar(tuple(range(10)), label=label) as progress:
             for thing in progress:
-                pass
+                fake_clock.advance_time()
 
+    monkeypatch.setattr(time, 'time', fake_clock.time)
     monkeypatch.setattr(click._termui_impl, 'isatty', lambda _: True)
     assert label in runner.invoke(cli, []).output
 
@@ -34,26 +47,31 @@ def __next__(self):
 
         next = __next__
 
+    fake_clock = FakeClock()
+
     @click.command()
     def cli():
         with click.progressbar(Hinted(10), label='test') as progress:
             for thing in progress:
-                pass
+                fake_clock.advance_time()
 
+    monkeypatch.setattr(time, 'time', fake_clock.time)
     monkeypatch.setattr(click._termui_impl, 'isatty', lambda _: True)
     result = runner.invoke(cli, [])
     assert result.exception is None
 
 
 def test_progressbar_hidden(runner, monkeypatch):
+    fake_clock = FakeClock()
     label = 'whatever'
 
     @click.command()
     def cli():
         with click.progressbar(tuple(range(10)), label=label) as progress:
             for thing in progress:
-                pass
+                fake_clock.advance_time()
 
+    monkeypatch.setattr(time, 'time', fake_clock.time)
     monkeypatch.setattr(click._termui_impl, 'isatty', lambda _: False)
     assert runner.invoke(cli, []).output == ''
 
@@ -91,16 +109,6 @@ def test_progressbar_yields_all_items(runner):
 
 
 def test_progressbar_update(runner, monkeypatch):
-    class FakeClock(object):
-        def __init__(self):
-            self.now = time.time()
-
-        def advance_time(self, seconds=1):
-            self.now += seconds
-
-        def time(self):
-            return self.now
-
     fake_clock = FakeClock()
 
     @click.command()
@@ -116,8 +124,7 @@ def cli():
 
     lines = [line for line in output.split('\n') if '[' in line]
 
-    assert '  0%' in lines[0]
-    assert ' 25%  00:00:03' in lines[1]
-    assert ' 50%  00:00:02' in lines[2]
-    assert ' 75%  00:00:01' in lines[3]
-    assert '100%          ' in lines[4]
+    assert ' 25%  00:00:03' in lines[0]
+    assert ' 50%  00:00:02' in lines[1]
+    assert ' 75%  00:00:01' in lines[2]
+    assert '100%          ' in lines[3]