view tests/test-hgweb-filelog.t @ 51681:522b4d729e89

mmap: populate the mapping by default

Without pre-population, accessing all data through a mmap can result in many
pagefault, reducing performance significantly. If the mmap is prepopulated, the
performance can no longer get slower than a full read.
(See benchmark number below)

In some cases were very few data is read, prepopulating can be overkill and
slower than populating on access (through page fault). So that behavior can be
controlled when the caller can pre-determine the best behavior.
(See benchmark number below)

In addition, testing with populating in a secondary thread yield great result
combining the best of each approach. This might be implemented in later
changesets.

In all cases, using mmap has a great effect on memory usage when many processes
run in parallel on the same machine.

### Benchmarks

# What did I run

A couple of month back I ran a large benchmark campaign to assess the impact of
various approach for using mmap with the revlog (and other files), it
highlighted a few benchmarks that capture the impact of the changes well. So to
validate this change I checked the following:

- log command displaying various revisions
  (read the changelog index)
- log command displaying the patch of listed revisions
  (read the changelog index, the manifest index and a few files indexes)
- unbundling a few revisions
  (read and write changelog, manifest and few files indexes, and walk the graph
  to update some cache)
- pushing a few revisions
  (read and write changelog, manifest and few files indexes, walk the graph to
  update some cache, performs various accesses locally and remotely during
  discovery)

Benchmarks were run using the default module policy (c+py) and the rust one. No
significant difference were found between the two implementation, so we will
present result using the default policy (unless otherwise specified).

I ran them on a few repositories :

- mercurial: a "public changeset only" copy of mercurial from 2018-08-01 using
  zstd compression and sparse-revlog

- pypy: a copy of pypy from 2018-08-01 using zstd compression and sparse-revlog

- netbeans: a copy of netbeans from 2018-08-01 using zstd compression and
  sparse-revlog

- mozilla-try: a copy of mozilla-try from 2019-02-18 using zstd compression and
  sparse-revlog

- mozilla-try persistent-nodemap: Same as the above but with a persistent
  nodemap. Used for the log --patch benchmark only

# Results

For the smaller repositories (mercurial, pypy), the impact of mmap is almost
imperceptible, other cost dominating the operation. The impact of prepopulating
is undiscernible in the benchmark we ran.

For larger repositories the benchmark support explanation given above:

On netbeans, the log can be about 1% faster without repopulation (for a
difference < 100ms) but unbundle becomes a bit slower, even when small.

### data-env-vars.name                             = netbeans-2018-08-01-zstd-sparse-revlog
  # benchmark.name                                 = hg.command.unbundle
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
  # benchmark.variants.source                      = unbundle
  # benchmark.variants.verbosity                   = quiet
with-populate: 0.240157
no-populate:   0.265087  (+10.38%, +0.02)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.459518
no-populate:   1.481290   (+1.49%, +0.02)
 ## benchmark.name                                 = hg.command.push
  # benchmark.variants.explicit-rev                = none
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.protocol                    = ssh
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 0.771919
no-populate:   0.792025   (+2.60%, +0.02)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.459518
no-populate:   1.481290   (+1.49%, +0.02)


For mozilla-try, the "slow down" from pre-populate for small `hg log` is more
visible, but still small in absolute time. (using rust value for the persistent
nodemap value to be relevant).

### data-env-vars.name            = mozilla-try-2019-02-18-ds2-pnm
  # benchmark.name                = hg.command.log
  # bin-env-vars.hg.flavor        = rust
  # benchmark.variants.patch      = yes
  # benchmark.variants.limit-rev  = 1
with-populate: 0.237813
no-populate:   0.229452   (-3.52%, -0.01)
  # benchmark.variants.limit-rev  = 10
  # benchmark.variants.patch      = yes
with-populate: 1.213578
no-populate:   1.205189
### data-env-vars.name            = mozilla-try-2019-02-18-zstd-sparse-revlog
  # benchmark.variants.limit-rev  = 1000
  # benchmark.variants.patch      = no
  # benchmark.variants.rev        = tip
with-populate: 0.198607
no-populate:   0.195038   (-1.80%, -0.00)

However pre-populating provide a significant boost on more complex operations
like unbundle or push:

### data-env-vars.name                             = mozilla-try-2019-02-18-zstd-sparse-revlog
  # benchmark.name                                 = hg.command.push
  # benchmark.variants.explicit-rev                = none
  # benchmark.variants.issue6528                   = disabled
  # benchmark.variants.protocol                    = ssh
  # benchmark.variants.reuse-external-delta-parent = yes
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 4.798632
no-populate:   4.953295   (+3.22%, +0.15)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 4.903618
no-populate:   5.014963   (+2.27%, +0.11)
 ## benchmark.name                                 = hg.command.unbundle
  # benchmark.variants.revs                        = any-1-extra-rev
with-populate: 1.423411
no-populate:   1.585365  (+11.38%, +0.16)
  # benchmark.variants.revs                        = any-100-extra-rev
with-populate: 1.537909
no-populate:   1.688489   (+9.79%, +0.15)

#require serve

  $ hg init test
  $ cd test
  $ echo b > b
  $ hg ci -Am "b"
  adding b
  $ echo a > a
  $ hg ci -Am "first a"
  adding a
  $ hg tag -r 1 a-tag
  $ hg bookmark -r 1 a-bookmark
  $ hg rm a
  $ hg ci -m "del a"
  $ hg branch a-branch
  marked working directory as branch a-branch
  (branches are permanent and global, did you want a bookmark?)
  $ echo b > a
  $ hg ci -Am "second a"
  adding a
  $ hg rm a
  $ hg ci -m "del2 a"
  $ hg mv b c
  $ hg ci -m "mv b"
  $ echo c >> c
  $ hg ci -m "change c"
  $ hg log -p
  changeset:   7:46c1a66bd8fc
  branch:      a-branch
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     change c
  
  diff -r c9637d3cc8ef -r 46c1a66bd8fc c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,2 @@
   b
  +c
  
  changeset:   6:c9637d3cc8ef
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     mv b
  
  diff -r 958bd88be4eb -r c9637d3cc8ef b
  --- a/b	Thu Jan 01 00:00:00 1970 +0000
  +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +0,0 @@
  -b
  diff -r 958bd88be4eb -r c9637d3cc8ef c
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b
  
  changeset:   5:958bd88be4eb
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     del2 a
  
  diff -r 3f41bc784e7e -r 958bd88be4eb a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +0,0 @@
  -b
  
  changeset:   4:3f41bc784e7e
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     second a
  
  diff -r 292258f86fdf -r 3f41bc784e7e a
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b
  
  changeset:   3:292258f86fdf
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     del a
  
  diff -r 94c9dd5ca9b4 -r 292258f86fdf a
  --- a/a	Thu Jan 01 00:00:00 1970 +0000
  +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +0,0 @@
  -a
  
  changeset:   2:94c9dd5ca9b4
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag a-tag for changeset 5ed941583260
  
  diff -r 5ed941583260 -r 94c9dd5ca9b4 .hgtags
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/.hgtags	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +5ed941583260248620985524192fdc382ef57c36 a-tag
  
  changeset:   1:5ed941583260
  bookmark:    a-bookmark
  tag:         a-tag
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     first a
  
  diff -r 6563da9dcf87 -r 5ed941583260 a
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +a
  
  changeset:   0:6563da9dcf87
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b
  
  diff -r 000000000000 -r 6563da9dcf87 b
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b
  
  $ hg serve -n test -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS

tip - two revisions

  $ (get-with-headers.py localhost:$HGPORT 'log/tip/a')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: a history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/a" title="Atom feed for test:a" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/a" title="RSS feed for test:a" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/tip">log</a></li>
  <li><a href="/graph/tip">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/tip">changeset</a></li>
  <li><a href="/file/tip">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/tip/a">file</a></li>
  <li><a href="/diff/tip/a">diff</a></li>
  <li><a href="/comparison/tip/a">comparison</a></li>
  <li><a href="/annotate/tip/a">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/tip/a">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/a" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log a @ 4:<a href="/rev/3f41bc784e7e">3f41bc784e7e</a>
   <span class="phase">draft</span> <span class="branchname">a-branch</span> 
   
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/tip/a?revcount=30">less</a>
  <a href="/log/tip/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/3f41bc784e7e">second a</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5ed941583260">first a</a>
     <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/tip/a?revcount=30">less</a>
  <a href="/log/tip/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  

second version - two revisions

  $ (get-with-headers.py localhost:$HGPORT 'log/4/a')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: a history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/a" title="Atom feed for test:a" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/a" title="RSS feed for test:a" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/4">log</a></li>
  <li><a href="/graph/4">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/4">changeset</a></li>
  <li><a href="/file/4">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/4/a">file</a></li>
  <li><a href="/diff/4/a">diff</a></li>
  <li><a href="/comparison/4/a">comparison</a></li>
  <li><a href="/annotate/4/a">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/4/a">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/a" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log a @ 4:<a href="/rev/3f41bc784e7e">3f41bc784e7e</a>
   <span class="phase">draft</span> <span class="branchname">a-branch</span> 
   
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/4/a?revcount=30">less</a>
  <a href="/log/4/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/3f41bc784e7e">second a</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5ed941583260">first a</a>
     <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/4/a?revcount=30">less</a>
  <a href="/log/4/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  

first deleted - one revision

  $ (get-with-headers.py localhost:$HGPORT 'log/3/a')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: a history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/a" title="Atom feed for test:a" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/a" title="RSS feed for test:a" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/3">log</a></li>
  <li><a href="/graph/3">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/3">changeset</a></li>
  <li><a href="/file/3">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/3/a">file</a></li>
  <li><a href="/diff/3/a">diff</a></li>
  <li><a href="/comparison/3/a">comparison</a></li>
  <li><a href="/annotate/3/a">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/3/a">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/a" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log a @ 1:<a href="/rev/5ed941583260">5ed941583260</a>
   <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
   
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/3/a?revcount=30">less</a>
  <a href="/log/3/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5ed941583260">first a</a>
     <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/3/a?revcount=30">less</a>
  <a href="/log/3/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  

first version - one revision

  $ (get-with-headers.py localhost:$HGPORT 'log/1/a')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: a history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/a" title="Atom feed for test:a" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/a" title="RSS feed for test:a" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/1">log</a></li>
  <li><a href="/graph/1">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/1">changeset</a></li>
  <li><a href="/file/1">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/1/a">file</a></li>
  <li><a href="/diff/1/a">diff</a></li>
  <li><a href="/comparison/1/a">comparison</a></li>
  <li><a href="/annotate/1/a">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/1/a">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/a" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log a @ 1:<a href="/rev/5ed941583260">5ed941583260</a>
   <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
   
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/1/a?revcount=30">less</a>
  <a href="/log/1/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5ed941583260">first a</a>
     <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/1/a?revcount=30">less</a>
  <a href="/log/1/a?revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  

before addition - error

  $ (get-with-headers.py localhost:$HGPORT 'log/0/a')
  404 Not Found
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: error</title>
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" width=75 height=90 border=0 alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog">log</a></li>
  <li><a href="/graph">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  </div>
  
  <div class="main">
  
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>error</h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="description">
  <p>
  An error occurred while processing your request:
  </p>
  <p>
  a@6563da9dcf87b1949716e38ff3e3dfaa3198eb06: not found in manifest
  </p>
  </div>
  </div>
  </div>
  
  
  
  </body>
  </html>
  
  [1]

  $ hg log -r 'followlines(c, 1:2, startrev=tip) and follow(c)'
  changeset:   0:6563da9dcf87
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b
  
  changeset:   7:46c1a66bd8fc
  branch:      a-branch
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     change c
  
  $ (get-with-headers.py localhost:$HGPORT 'log/tip/c?linerange=1:2')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: c history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/c" title="Atom feed for test:c" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/c" title="RSS feed for test:c" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/tip">log</a></li>
  <li><a href="/graph/tip">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/tip">changeset</a></li>
  <li><a href="/file/tip">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/tip/c">file</a></li>
  <li><a href="/diff/tip/c">diff</a></li>
  <li><a href="/comparison/tip/c">comparison</a></li>
  <li><a href="/annotate/tip/c">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/tip/c">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/c" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log c @ 7:<a href="/rev/46c1a66bd8fc">46c1a66bd8fc</a>
   <span class="phase">draft</span> <span class="branchhead">a-branch</span> <span class="tag">tip</span> 
    (following lines 1:2 <a href="/log/tip/c">all revisions for this file</a>)
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=1%3A2&revcount=30">less</a>
  <a href="/log/tip/c?linerange=1%3A2&revcount=120">more</a>
  | </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/46c1a66bd8fc">change c</a>
     <span class="phase">draft</span> <span class="branchhead">a-branch</span> <span class="tag">tip</span> 
    </td>
   </tr>
   
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/6563da9dcf87">b</a>
     <span class="phase">draft</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=1%3A2&revcount=30">less</a>
  <a href="/log/tip/c?linerange=1%3A2&revcount=120">more</a>
  | 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  
  $ (get-with-headers.py localhost:$HGPORT 'log/tip/c?linerange=1%3A2&revcount=1')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: c history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/c" title="Atom feed for test:c" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/c" title="RSS feed for test:c" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/tip?revcount=1">log</a></li>
  <li><a href="/graph/tip?revcount=1">graph</a></li>
  <li><a href="/tags?revcount=1">tags</a></li>
  <li><a href="/bookmarks?revcount=1">bookmarks</a></li>
  <li><a href="/branches?revcount=1">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/tip?revcount=1">changeset</a></li>
  <li><a href="/file/tip?revcount=1">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/tip/c?revcount=1">file</a></li>
  <li><a href="/diff/tip/c?revcount=1">diff</a></li>
  <li><a href="/comparison/tip/c?revcount=1">comparison</a></li>
  <li><a href="/annotate/tip/c?revcount=1">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/tip/c">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help?revcount=1">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/c" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log c @ 7:<a href="/rev/46c1a66bd8fc?revcount=1">46c1a66bd8fc</a>
   <span class="phase">draft</span> <span class="branchhead">a-branch</span> <span class="tag">tip</span> 
    (following lines 1:2 <a href="/log/tip/c?revcount=1">all revisions for this file</a>)
  </h3>
  
  
  <form class="search" action="/log">
  <input type="hidden" name="revcount" value="1" />
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=1%3A2&revcount=1">less</a>
  <a href="/log/tip/c?linerange=1%3A2&revcount=2">more</a>
  | </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/46c1a66bd8fc?revcount=1">change c</a>
     <span class="phase">draft</span> <span class="branchhead">a-branch</span> <span class="tag">tip</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=1%3A2&revcount=1">less</a>
  <a href="/log/tip/c?linerange=1%3A2&revcount=2">more</a>
  | 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  
  $ (get-with-headers.py localhost:$HGPORT 'log/3/a?linerange=1' --headeronly)
  400 invalid linerange parameter
  [1]
  $ (get-with-headers.py localhost:$HGPORT 'log/3/a?linerange=1:a' --headeronly)
  400 invalid linerange parameter
  [1]
  $ (get-with-headers.py localhost:$HGPORT 'log/3/a?linerange=1:2&linerange=3:4' --headeronly)
  400 redundant linerange parameter
  [1]
  $ (get-with-headers.py localhost:$HGPORT 'log/3/a?linerange=3:2' --headeronly)
  400 line range must be positive
  [1]
  $ (get-with-headers.py localhost:$HGPORT 'log/3/a?linerange=0:1' --headeronly)
  400 fromline must be strictly positive
  [1]

should show base link, use spartan because it shows it

  $ (get-with-headers.py localhost:$HGPORT 'log/tip/c?style=spartan')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
  <html>
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png">
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: c history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/c" title="Atom feed for test:c">
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/c" title="RSS feed for test:c">
  </head>
  <body>
  
  <div class="buttons">
  <a href="/log?style=spartan">changelog</a>
  <a href="/shortlog?style=spartan">shortlog</a>
  <a href="/graph?style=spartan">graph</a>
  <a href="/tags?style=spartan">tags</a>
  <a href="/branches?style=spartan">branches</a>
  <a href="/file/tip/c?style=spartan">file</a>
  <a href="/annotate/tip/c?style=spartan">annotate</a>
  <a href="/help?style=spartan">help</a>
  <a type="application/rss+xml" href="/rss-log/tip/c">rss</a>
  <a type="application/atom+xml" href="/atom-log/tip/c" title="Atom feed for test:c">atom</a>
  </div>
  
  <h2><a href="/">Mercurial</a>  / c revision history</h2>
  
  <p>navigate: <small class="navigate"><a href="/log/c9637d3cc8ef/c?style=spartan">(0)</a> <a href="/log/tip/c?style=spartan">tip</a> </small></p>
  
  <table class="logEntry parity0">
   <tr>
    <th class="label"><span class="age">Thu, 01 Jan 1970 00:00:00 +0000</span>:</th>
    <th class="firstline"><a href="/rev/46c1a66bd8fc?style=spartan">change c</a></th>
   </tr>
   <tr>
    <th class="revision">revision 1:</th>
    <td class="node">
     <a href="/file/46c1a66bd8fc/c?style=spartan">46c1a66bd8fc</a>
     <a href="/diff/46c1a66bd8fc/c?style=spartan">(diff)</a>
     <a href="/annotate/46c1a66bd8fc/c?style=spartan">(annotate)</a>
    </td>
   </tr>
   
   <tr>
    <th class="author">author:</th>
    <td class="author">&#116;&#101;&#115;&#116;</td>
   </tr>
   <tr>
    <th class="date">date:</th>
    <td class="date">Thu, 01 Jan 1970 00:00:00 +0000</td>
   </tr>
  </table>
  
  
  <table class="logEntry parity1">
   <tr>
    <th class="label"><span class="age">Thu, 01 Jan 1970 00:00:00 +0000</span>:</th>
    <th class="firstline"><a href="/rev/c9637d3cc8ef?style=spartan">mv b</a></th>
   </tr>
   <tr>
    <th class="revision">revision 0:</th>
    <td class="node">
     <a href="/file/c9637d3cc8ef/c?style=spartan">c9637d3cc8ef</a>
     <a href="/diff/c9637d3cc8ef/c?style=spartan">(diff)</a>
     <a href="/annotate/c9637d3cc8ef/c?style=spartan">(annotate)</a>
    </td>
   </tr>
   
  <tr>
  <th>base:</th>
  <td>
  <a href="/file/1e88685f5dde/b?style=spartan">
  b@1e88685f5dde
  </a>
  </td>
  </tr>
   <tr>
    <th class="author">author:</th>
    <td class="author">&#116;&#101;&#115;&#116;</td>
   </tr>
   <tr>
    <th class="date">date:</th>
    <td class="date">Thu, 01 Jan 1970 00:00:00 +0000</td>
   </tr>
  </table>
  
  
  
  
  
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" width=75 height=90 border=0 alt="mercurial"></a>
  </div>
  
  </body>
  </html>
  

filelog with patch

  $ (get-with-headers.py localhost:$HGPORT 'log/4/a?patch=1')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: a history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/a" title="Atom feed for test:a" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/a" title="RSS feed for test:a" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/4">log</a></li>
  <li><a href="/graph/4">graph</a></li>
  <li><a href="/tags">tags</a></li>
  <li><a href="/bookmarks">bookmarks</a></li>
  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/4">changeset</a></li>
  <li><a href="/file/4">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/4/a">file</a></li>
  <li><a href="/diff/4/a">diff</a></li>
  <li><a href="/comparison/4/a">comparison</a></li>
  <li><a href="/annotate/4/a">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/4/a">raw</a></li>
  </ul>
  <ul>
  <li><a href="/help">help</a></li>
  </ul>
  <div class="atom-logo">
  <a href="/atom-log/tip/a" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log a @ 4:<a href="/rev/3f41bc784e7e">3f41bc784e7e</a>
   <span class="phase">draft</span> <span class="branchname">a-branch</span> 
   
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/4/a?patch=1&revcount=30">less</a>
  <a href="/log/4/a?patch=1&revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/3f41bc784e7e">second a</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="3f41bc784e7e-l1.1" class="minusline">--- /dev/null	Thu Jan 01 00:00:00 1970 +0000</span><a href="#3f41bc784e7e-l1.1"></a>
  <span id="3f41bc784e7e-l1.2" class="plusline">+++ b/a	Thu Jan 01 00:00:00 1970 +0000</span><a href="#3f41bc784e7e-l1.2"></a>
  <span id="3f41bc784e7e-l1.3" class="atline">@@ -0,0 +1,1 @@</span><a href="#3f41bc784e7e-l1.3"></a>
  <span id="3f41bc784e7e-l1.4" class="plusline">+b</span><a href="#3f41bc784e7e-l1.4"></a></pre></div></td></tr>
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5ed941583260">first a</a>
     <span class="phase">draft</span> <span class="tag">a-tag</span> <span class="tag">a-bookmark</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="5ed941583260-l1.1" class="minusline">--- /dev/null	Thu Jan 01 00:00:00 1970 +0000</span><a href="#5ed941583260-l1.1"></a>
  <span id="5ed941583260-l1.2" class="plusline">+++ b/a	Thu Jan 01 00:00:00 1970 +0000</span><a href="#5ed941583260-l1.2"></a>
  <span id="5ed941583260-l1.3" class="atline">@@ -0,0 +1,1 @@</span><a href="#5ed941583260-l1.3"></a>
  <span id="5ed941583260-l1.4" class="plusline">+a</span><a href="#5ed941583260-l1.4"></a></pre></div></td></tr>
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/4/a?patch=1&revcount=30">less</a>
  <a href="/log/4/a?patch=1&revcount=120">more</a>
  | <a href="/log/5ed941583260/a">(0)</a> <a href="/log/tip/a">tip</a> 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  
filelog with 'linerange' and 'patch'

  $ cat c
  b
  c
  $ cat <<EOF > c
  > 0
  > 0
  > b
  > c+
  > 
  > a
  > a
  > 
  > d
  > e
  > f
  > EOF
  $ hg ci -m 'make c bigger and touch its beginning' c
  $ cat <<EOF > c
  > 0
  > 0
  > b
  > c+
  > 
  > a
  > a
  > 
  > d
  > e+
  > f
  > EOF
  $ hg ci -m 'just touch end of c' c
  $ cat <<EOF > c
  > 0
  > 0
  > b
  > c++
  > 
  > a
  > a
  > 
  > d
  > e+
  > f
  > EOF
  $ hg ci -m 'touch beginning of c' c
  $ cat <<EOF > c
  > 0
  > 0
  > b-
  > c++
  > 
  > a
  > a
  > 
  > d
  > e+
  > f+
  > EOF
  $ hg ci -m 'touching beginning and end of c' c
  $ echo c > cc
  $ hg ci -Am 'tip does not touch c' cc
  $ hg log -r 'followlines(c, 3:4, startrev=tip) and follow(c)' -p
  changeset:   0:6563da9dcf87
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     b
  
  diff -r 000000000000 -r 6563da9dcf87 b
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +b
  
  changeset:   7:46c1a66bd8fc
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     change c
  
  diff -r c9637d3cc8ef -r 46c1a66bd8fc c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,2 @@
   b
  +c
  
  changeset:   8:5c6574614c37
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     make c bigger and touch its beginning
  
  diff -r 46c1a66bd8fc -r 5c6574614c37 c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,2 +1,11 @@
  +0
  +0
   b
  -c
  +c+
  +
  +a
  +a
  +
  +d
  +e
  +f
  
  changeset:   10:e95928d60479
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     touch beginning of c
  
  diff -r e1d3e9c5a23f -r e95928d60479 c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,7 +1,7 @@
   0
   0
   b
  -c+
  +c++
   
   a
   a
  
  changeset:   11:fb9bc322513a
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     touching beginning and end of c
  
  diff -r e95928d60479 -r fb9bc322513a c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,6 +1,6 @@
   0
   0
  -b
  +b-
   c++
   
   a
  @@ -8,4 +8,4 @@
   
   d
   e+
  -f
  +f+
  
  $ (get-with-headers.py localhost:$HGPORT 'log/tip/c?linerange=3:4&patch=')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: c history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/c" title="Atom feed for test:c" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/c" title="RSS feed for test:c" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/tip">log</a></li>
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  <li><a href="/branches">branches</a></li>
  </ul>
  <ul>
  <li><a href="/rev/tip">changeset</a></li>
  <li><a href="/file/tip">browse</a></li>
  </ul>
  <ul>
  <li><a href="/file/tip/c">file</a></li>
  <li><a href="/diff/tip/c">diff</a></li>
  <li><a href="/comparison/tip/c">comparison</a></li>
  <li><a href="/annotate/tip/c">annotate</a></li>
  <li class="active">file log</li>
  <li><a href="/raw-file/tip/c">raw</a></li>
  </ul>
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  <li><a href="/help">help</a></li>
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  <div class="atom-logo">
  <a href="/atom-log/tip/c" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log c @ 12:<a href="/rev/6e4182052f7b">6e4182052f7b</a>
   <span class="phase">draft</span> <span class="branchhead">a-branch</span> <span class="tag">tip</span> 
    (following lines 3:4 <a href="/log/tip/c">all revisions for this file</a>)
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=3%3A4&patch=&revcount=30">less</a>
  <a href="/log/tip/c?linerange=3%3A4&patch=&revcount=120">more</a>
  | </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/fb9bc322513a">touching beginning and end of c</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="fb9bc322513a-l1.1" class="minusline">--- a/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#fb9bc322513a-l1.1"></a>
  <span id="fb9bc322513a-l1.2" class="plusline">+++ b/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#fb9bc322513a-l1.2"></a>
  <span id="fb9bc322513a-l1.3" class="atline">@@ -1,6 +1,6 @@</span><a href="#fb9bc322513a-l1.3"></a>
  <span id="fb9bc322513a-l1.4"> 0</span><a href="#fb9bc322513a-l1.4"></a>
  <span id="fb9bc322513a-l1.5"> 0</span><a href="#fb9bc322513a-l1.5"></a>
  <span id="fb9bc322513a-l1.6" class="minusline">-b</span><a href="#fb9bc322513a-l1.6"></a>
  <span id="fb9bc322513a-l1.7" class="plusline">+b-</span><a href="#fb9bc322513a-l1.7"></a>
  <span id="fb9bc322513a-l1.8"> c++</span><a href="#fb9bc322513a-l1.8"></a>
  <span id="fb9bc322513a-l1.9"> </span><a href="#fb9bc322513a-l1.9"></a>
  <span id="fb9bc322513a-l1.10"> a</span><a href="#fb9bc322513a-l1.10"></a></pre></div></td></tr>
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/e95928d60479">touch beginning of c</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="e95928d60479-l1.1" class="minusline">--- a/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#e95928d60479-l1.1"></a>
  <span id="e95928d60479-l1.2" class="plusline">+++ b/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#e95928d60479-l1.2"></a>
  <span id="e95928d60479-l1.3" class="atline">@@ -1,7 +1,7 @@</span><a href="#e95928d60479-l1.3"></a>
  <span id="e95928d60479-l1.4"> 0</span><a href="#e95928d60479-l1.4"></a>
  <span id="e95928d60479-l1.5"> 0</span><a href="#e95928d60479-l1.5"></a>
  <span id="e95928d60479-l1.6"> b</span><a href="#e95928d60479-l1.6"></a>
  <span id="e95928d60479-l1.7" class="minusline">-c+</span><a href="#e95928d60479-l1.7"></a>
  <span id="e95928d60479-l1.8" class="plusline">+c++</span><a href="#e95928d60479-l1.8"></a>
  <span id="e95928d60479-l1.9"> </span><a href="#e95928d60479-l1.9"></a>
  <span id="e95928d60479-l1.10"> a</span><a href="#e95928d60479-l1.10"></a>
  <span id="e95928d60479-l1.11"> a</span><a href="#e95928d60479-l1.11"></a></pre></div></td></tr>
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5c6574614c37">make c bigger and touch its beginning</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="5c6574614c37-l1.1" class="minusline">--- a/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#5c6574614c37-l1.1"></a>
  <span id="5c6574614c37-l1.2" class="plusline">+++ b/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#5c6574614c37-l1.2"></a>
  <span id="5c6574614c37-l1.3" class="atline">@@ -1,2 +1,11 @@</span><a href="#5c6574614c37-l1.3"></a>
  <span id="5c6574614c37-l1.4" class="plusline">+0</span><a href="#5c6574614c37-l1.4"></a>
  <span id="5c6574614c37-l1.5" class="plusline">+0</span><a href="#5c6574614c37-l1.5"></a>
  <span id="5c6574614c37-l1.6"> b</span><a href="#5c6574614c37-l1.6"></a>
  <span id="5c6574614c37-l1.7" class="minusline">-c</span><a href="#5c6574614c37-l1.7"></a>
  <span id="5c6574614c37-l1.8" class="plusline">+c+</span><a href="#5c6574614c37-l1.8"></a>
  <span id="5c6574614c37-l1.9" class="plusline">+</span><a href="#5c6574614c37-l1.9"></a>
  <span id="5c6574614c37-l1.10" class="plusline">+a</span><a href="#5c6574614c37-l1.10"></a>
  <span id="5c6574614c37-l1.11" class="plusline">+a</span><a href="#5c6574614c37-l1.11"></a>
  <span id="5c6574614c37-l1.12" class="plusline">+</span><a href="#5c6574614c37-l1.12"></a>
  <span id="5c6574614c37-l1.13" class="plusline">+d</span><a href="#5c6574614c37-l1.13"></a>
  <span id="5c6574614c37-l1.14" class="plusline">+e</span><a href="#5c6574614c37-l1.14"></a>
  <span id="5c6574614c37-l1.15" class="plusline">+f</span><a href="#5c6574614c37-l1.15"></a></pre></div></td></tr>
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/46c1a66bd8fc">change c</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="46c1a66bd8fc-l1.1" class="minusline">--- a/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#46c1a66bd8fc-l1.1"></a>
  <span id="46c1a66bd8fc-l1.2" class="plusline">+++ b/c	Thu Jan 01 00:00:00 1970 +0000</span><a href="#46c1a66bd8fc-l1.2"></a>
  <span id="46c1a66bd8fc-l1.3" class="atline">@@ -1,1 +1,2 @@</span><a href="#46c1a66bd8fc-l1.3"></a>
  <span id="46c1a66bd8fc-l1.4"> b</span><a href="#46c1a66bd8fc-l1.4"></a>
  <span id="46c1a66bd8fc-l1.5" class="plusline">+c</span><a href="#46c1a66bd8fc-l1.5"></a></pre></div></td></tr>
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/6563da9dcf87">b</a>
     <span class="phase">draft</span> 
    </td>
   </tr>
   <tr><td colspan="3"><div class="bottomline inc-lineno"><pre class="sourcelines wrap">
  <span id="6563da9dcf87-l1.1" class="minusline">--- /dev/null	Thu Jan 01 00:00:00 1970 +0000</span><a href="#6563da9dcf87-l1.1"></a>
  <span id="6563da9dcf87-l1.2" class="plusline">+++ b/b	Thu Jan 01 00:00:00 1970 +0000</span><a href="#6563da9dcf87-l1.2"></a></pre></div></td></tr>
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/tip/c?linerange=3%3A4&patch=&revcount=30">less</a>
  <a href="/log/tip/c?linerange=3%3A4&patch=&revcount=120">more</a>
  | 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  
  $ hg log -r 'followlines(c, 3:4, startrev=8, descend=True) and follow(c)' -p
  changeset:   8:5c6574614c37
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     make c bigger and touch its beginning
  
  diff -r 46c1a66bd8fc -r 5c6574614c37 c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,2 +1,11 @@
  +0
  +0
   b
  -c
  +c+
  +
  +a
  +a
  +
  +d
  +e
  +f
  
  changeset:   10:e95928d60479
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     touch beginning of c
  
  diff -r e1d3e9c5a23f -r e95928d60479 c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,7 +1,7 @@
   0
   0
   b
  -c+
  +c++
   
   a
   a
  
  changeset:   11:fb9bc322513a
  branch:      a-branch
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     touching beginning and end of c
  
  diff -r e95928d60479 -r fb9bc322513a c
  --- a/c	Thu Jan 01 00:00:00 1970 +0000
  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,6 +1,6 @@
   0
   0
  -b
  +b-
   c++
   
   a
  @@ -8,4 +8,4 @@
   
   d
   e+
  -f
  +f+
  
  $ (get-with-headers.py localhost:$HGPORT 'log/8/c?linerange=3:4&descend=')
  200 Script output follows
  
  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
  <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en-US">
  <head>
  <link rel="icon" href="/static/hgicon.png" type="image/png" />
  <meta name="robots" content="index, nofollow" />
  <link rel="stylesheet" href="/static/style-paper.css" type="text/css" />
  <script type="text/javascript" src="/static/mercurial.js"></script>
  
  <title>test: c history</title>
  <link rel="alternate" type="application/atom+xml"
     href="/atom-log/tip/c" title="Atom feed for test:c" />
  <link rel="alternate" type="application/rss+xml"
     href="/rss-log/tip/c" title="RSS feed for test:c" />
  </head>
  <body>
  
  <div class="container">
  <div class="menu">
  <div class="logo">
  <a href="https://mercurial-scm.org/">
  <img src="/static/hglogo.png" alt="mercurial" /></a>
  </div>
  <ul>
  <li><a href="/shortlog/8">log</a></li>
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  </ul>
  <ul>
  <li><a href="/file/8/c">file</a></li>
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  <div class="atom-logo">
  <a href="/atom-log/tip/c" title="subscribe to atom feed">
  <img class="atom-logo" src="/static/feed-icon-14x14.png" alt="atom feed" />
  </a>
  </div>
  </div>
  
  <div class="main">
  <h2 class="breadcrumb"><a href="/">Mercurial</a> </h2>
  <h3>
   log c @ 8:<a href="/rev/5c6574614c37">5c6574614c37</a>
   <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    (following lines 3:4, descending <a href="/log/8/c">all revisions for this file</a>)
  </h3>
  
  
  <form class="search" action="/log">
  
  <p><input name="rev" id="search1" type="text" size="30" value="" /></p>
  <div id="hint">Find changesets by keywords (author, files, the commit message), revision
  number or hash, or <a href="/help/revsets">revset expression</a>.</div>
  </form>
  
  <div class="navigate">
  <a href="/log/8/c?descend=&linerange=3%3A4&revcount=30">less</a>
  <a href="/log/8/c?descend=&linerange=3%3A4&revcount=120">more</a>
  | </div>
  
  <table class="bigtable">
  <thead>
   <tr>
    <th class="age">age</th>
    <th class="author">author</th>
    <th class="description">description</th>
   </tr>
  </thead>
  <tbody class="stripes2">
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/5c6574614c37">make c bigger and touch its beginning</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/e95928d60479">touch beginning of c</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   
   <tr>
    <td class="age">Thu, 01 Jan 1970 00:00:00 +0000</td>
    <td class="author">test</td>
    <td class="description">
     <a href="/rev/fb9bc322513a">touching beginning and end of c</a>
     <span class="phase">draft</span> <span class="branchname">a-branch</span> 
    </td>
   </tr>
   
  
  </tbody>
  </table>
  
  <div class="navigate">
  <a href="/log/8/c?descend=&linerange=3%3A4&revcount=30">less</a>
  <a href="/log/8/c?descend=&linerange=3%3A4&revcount=120">more</a>
  | 
  </div>
  
  </div>
  </div>
  
  
  
  </body>
  </html>
  

rss log

  $ (get-with-headers.py localhost:$HGPORT 'rss-log/tip/a')
  200 Script output follows
  
  <?xml version="1.0" encoding="ascii"?>
  <rss version="2.0">
    <channel>
      <link>http://*:$HGPORT/</link> (glob)
      <language>en-us</language>
  
      <title>test: a history</title>
      <description>a revision history</description>
      <item>
      <title>second a</title>
      <link>http://*:$HGPORT/log/3f41bc784e7e/a</link> (glob)
      <description><![CDATA[second a]]></description>
      <author>&#116;&#101;&#115;&#116;</author>
      <pubDate>Thu, 01 Jan 1970 00:00:00 +0000</pubDate>
  </item>
  <item>
      <title>first a</title>
      <link>http://*:$HGPORT/log/5ed941583260/a</link> (glob)
      <description><![CDATA[first a]]></description>
      <author>&#116;&#101;&#115;&#116;</author>
      <pubDate>Thu, 01 Jan 1970 00:00:00 +0000</pubDate>
  </item>
  
    </channel>
  </rss>

atom log

  $ (get-with-headers.py localhost:$HGPORT 'atom-log/tip/a')
  200 Script output follows
  
  <?xml version="1.0" encoding="ascii"?>
  <feed xmlns="http://www.w3.org/2005/Atom">
   <id>http://*:$HGPORT/atom-log/tip/a</id> (glob)
   <link rel="self" href="http://*:$HGPORT/atom-log/tip/a"/> (glob)
   <title>test: a history</title>
   <updated>1970-01-01T00:00:00+00:00</updated>
  
   <entry>
    <title>[a-branch] second a</title>
    <id>http://*:$HGPORT/#changeset-3f41bc784e7e73035c6d47112c6cc7efb673adf8</id> (glob)
    <link href="http://*:$HGPORT/rev/3f41bc784e7e"/> (glob)
    <author>
     <name>test</name>
     <email>&#116;&#101;&#115;&#116;</email>
    </author>
    <updated>1970-01-01T00:00:00+00:00</updated>
    <published>1970-01-01T00:00:00+00:00</published>
    <content type="xhtml">
     <table xmlns="http://www.w3.org/1999/xhtml">
      <tr>
       <th style="text-align:left;">changeset</th>
       <td>3f41bc784e7e</td>
      </tr>
      <tr>
       <th style="text-align:left;">branch</th>
       <td>a-branch</td>
      </tr>
      <tr>
       <th style="text-align:left;">bookmark</th>
       <td></td>
      </tr>
      <tr>
       <th style="text-align:left;">tag</th>
       <td></td>
      </tr>
      <tr>
       <th style="text-align:left;">user</th>
       <td>&#116;&#101;&#115;&#116;</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">description</th>
       <td>second a</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">files</th>
       <td></td>
      </tr>
     </table>
    </content>
   </entry>
   <entry>
    <title>first a</title>
    <id>http://*:$HGPORT/#changeset-5ed941583260248620985524192fdc382ef57c36</id> (glob)
    <link href="http://*:$HGPORT/rev/5ed941583260"/> (glob)
    <author>
     <name>test</name>
     <email>&#116;&#101;&#115;&#116;</email>
    </author>
    <updated>1970-01-01T00:00:00+00:00</updated>
    <published>1970-01-01T00:00:00+00:00</published>
    <content type="xhtml">
     <table xmlns="http://www.w3.org/1999/xhtml">
      <tr>
       <th style="text-align:left;">changeset</th>
       <td>5ed941583260</td>
      </tr>
      <tr>
       <th style="text-align:left;">branch</th>
       <td></td>
      </tr>
      <tr>
       <th style="text-align:left;">bookmark</th>
       <td>a-bookmark</td>
      </tr>
      <tr>
       <th style="text-align:left;">tag</th>
       <td>a-tag</td>
      </tr>
      <tr>
       <th style="text-align:left;">user</th>
       <td>&#116;&#101;&#115;&#116;</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">description</th>
       <td>first a</td>
      </tr>
      <tr>
       <th style="text-align:left;vertical-align:top;">files</th>
       <td></td>
      </tr>
     </table>
    </content>
   </entry>
  
  </feed>

errors

  $ cat errors.log

  $ cd ..