view tests/test-ui-verbosity.py.out @ 19387:f2e4fdb3dd27

hgweb: code selection without line numbers in file source view

All the source lines are put in a <pre> tag, which gives correct display and
copy&paste in both Chromium (WebKit) and FireFox: line numbers are not copied,
all the tabs and spaces are kept. This doesn't change the visual appearance
of the view compared to current hgweb version and doesn't use any JS code.
Also, stripes in this view are now generated clientside with CSS.

This implementation is chosen because other variants have important issues:

Strategy             FF              Chrome

current             D,LT,E,T,L        D,L
pre                 S,NW              S,NW
pre/div/nbsp        LT,E,T,TS,NW      TS,NW
pre/div/br          LT,E,T,NW         NW
ol/li/nbsp          LT,E,T,TS,AJ      TS,AJ
ol/li/br            LT,E,T,AJ         AJ
pre/span            LV                LV

Legend

Strategies:
- current: implemented in hgweb before this patch, i.e. divs for each line,
and line numbers links in the div too
- pre: the whole code in one pre tag with newlines, all line numbers
in another one with 'float: left'
- pre/div/{nbsp,br}: same as just 'pre', but separate divs for each line and
&nbsp; or <br> instead of empty lines (otherwise they are not copied at all)
- ol/li/{nbsp,br}: a single ol with li's and divs for each line,
&nbsp; or <br> same as in previous strategy
- pre/span: this patch

Problems:
D = (very minor) display problems, like wrong width of leading tabs
LT = loses leading/trailing whitespace
E = loses embedded whitespace
B = loses blank lines
T = loses tabs
L = selects line numbers
LV = (only) visually selects line numbers
LVE = (only) visually selects line numbers at empty lines
S = no stripes (and no ability to easily highlight
lines-which-are-linked-at in the future)
TS = space copied instead of empty line
AJ = get anchor links only with JS (they work even without)
NW = no linewrap easily possible (in future)

As for browser versions compatibility, the CSS tricks used are supported in
(according to caniuse.com):
a) line numbers generation with 'content:' property and CSS counters:
IE 8+, all other popular browsers (in pre-WebKit Opera numbers are being copied)
b) stripes ('nth-child' selector):
IE 8+, FF 3.5+, Safari 3.2+, Opera 9.5+, all other popular browsers
c) line numbers are not visually selected ('user-select:' property):
IE 10+, Opera 15.0+, all other popular browsers

This patch is based on a demo implementation by
Martin Geisler <[e-mail]>.

      hgrc settings    command line options      final result   
    quiet verbo debug   quiet verbo debug      quiet verbo debug
 0  False False False   False False False  ->  False False False
 1   True False False   False False False  ->   True False False
 2  False  True False   False False False  ->  False  True False
 3   True  True False   False False False  ->  False False False
 4  False False  True   False False False  ->  False  True  True
 5   True False  True   False False False  ->  False  True  True
 6  False  True  True   False False False  ->  False  True  True
 7   True  True  True   False False False  ->  False  True  True
 8  False False False    True False False  ->   True False False
 9   True False False    True False False  ->   True False False
10  False  True False    True False False  ->   True False False
11   True  True False    True False False  ->   True False False
12  False False  True    True False False  ->   True False False
13   True False  True    True False False  ->   True False False
14  False  True  True    True False False  ->   True False False
15   True  True  True    True False False  ->   True False False
16  False False False   False  True False  ->  False  True False
17   True False False   False  True False  ->  False  True False
18  False  True False   False  True False  ->  False  True False
19   True  True False   False  True False  ->  False  True False
20  False False  True   False  True False  ->  False  True False
21   True False  True   False  True False  ->  False  True False
22  False  True  True   False  True False  ->  False  True False
23   True  True  True   False  True False  ->  False  True False
24  False False False    True  True False  ->  False False False
25   True False False    True  True False  ->  False False False
26  False  True False    True  True False  ->  False False False
27   True  True False    True  True False  ->  False False False
28  False False  True    True  True False  ->  False False False
29   True False  True    True  True False  ->  False False False
30  False  True  True    True  True False  ->  False False False
31   True  True  True    True  True False  ->  False False False
32  False False False   False False  True  ->  False  True  True
33   True False False   False False  True  ->  False  True  True
34  False  True False   False False  True  ->  False  True  True
35   True  True False   False False  True  ->  False  True  True
36  False False  True   False False  True  ->  False  True  True
37   True False  True   False False  True  ->  False  True  True
38  False  True  True   False False  True  ->  False  True  True
39   True  True  True   False False  True  ->  False  True  True
40  False False False    True False  True  ->  False  True  True
41   True False False    True False  True  ->  False  True  True
42  False  True False    True False  True  ->  False  True  True
43   True  True False    True False  True  ->  False  True  True
44  False False  True    True False  True  ->  False  True  True
45   True False  True    True False  True  ->  False  True  True
46  False  True  True    True False  True  ->  False  True  True
47   True  True  True    True False  True  ->  False  True  True
48  False False False   False  True  True  ->  False  True  True
49   True False False   False  True  True  ->  False  True  True
50  False  True False   False  True  True  ->  False  True  True
51   True  True False   False  True  True  ->  False  True  True
52  False False  True   False  True  True  ->  False  True  True
53   True False  True   False  True  True  ->  False  True  True
54  False  True  True   False  True  True  ->  False  True  True
55   True  True  True   False  True  True  ->  False  True  True
56  False False False    True  True  True  ->  False  True  True
57   True False False    True  True  True  ->  False  True  True
58  False  True False    True  True  True  ->  False  True  True
59   True  True False    True  True  True  ->  False  True  True
60  False False  True    True  True  True  ->  False  True  True
61   True False  True    True  True  True  ->  False  True  True
62  False  True  True    True  True  True  ->  False  True  True
63   True  True  True    True  True  True  ->  False  True  True