view tests/test-empty-file.t @ 26362:3bfc473f4d33

gitweb, monoblue: fix vertical align of spans in .sourcelines

Empty lines in file view could produce an inexplicable margin before the next
line (most noticeable in browsers on webkit/blink engine). That was making
empty lines seem taller than the rest.

Instead of using default vertical align, let's set it to 'top'.

This issue is actually present in paper, and only recently got into gitweb
(2239626369f5) and monoblue (119202d4d7a4). There's a bit more to it in paper,
so that will be dealt with in a future patch.

Recipe to see live: preferably using a webkit/blink browser, such as chromium,
browse a file with empty lines, e.g. https://selenic.com/hg/file/3.5/README#l8
Selecting a block of text that includes empty lines will reveal white "breaks"
in the selection. Highlighted line (#l8) also shows such a break below itself.

  $ hg init a
  $ cd a
  $ touch empty1
  $ hg add empty1
  $ hg commit -m 'add empty1'

  $ touch empty2
  $ hg add empty2
  $ hg commit -m 'add empty2'

  $ hg up -C 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ touch empty3
  $ hg add empty3
  $ hg commit -m 'add empty3'
  created new head

  $ hg heads
  changeset:   2:a1cb177e0d44
  tag:         tip
  parent:      0:1e1d9c4e5b64
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add empty3
  
  changeset:   1:097d2b0e17f6
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     add empty2
  

  $ hg merge 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

Before changeset 05257fd28591, we didn't notice the
empty file that came from rev 1:

  $ hg status
  M empty2
  $ hg commit -m merge
  $ hg manifest --debug tip
  b80de5d138758541c5f05265ad144ab9fa86d1db 644   empty1
  b80de5d138758541c5f05265ad144ab9fa86d1db 644   empty2
  b80de5d138758541c5f05265ad144ab9fa86d1db 644   empty3

  $ cd ..