view doc/gendoc.py @ 15462:2b1ec74c961f stable

mdiff/patch: fix bad hunk handling for unified diffs with zero context

Prior to this patch "hg diff -U0", i.e., zero lines of context, would
output hunk headers with a start line one greater than what GNU patch
and git output. Guido van Rossum documents the unified diff format[1]
as having a start line value "one lower than one would expect" for
zero length hunks.

Comparing the behaviour of the three systems prior to this patch in
transforming

  c1
  c3

to

  c1
  c2
  c3

- GNU "diff -U0" reports the hunk as "@@ -1,0 +2 @@"
- "git diff -U0" reports the hunk as "@@ -1,0 +2 @@"
- "hg diff -U0" reports the hunk as "@@ -2,0 +2,1 @@"

After this patch, "hg diff -U0" reports "@@ -1,0 +2,1 @@".

Since "hg export --config diff.unified=0" outputs zero-context unified
diffs, "hg import" has also been updated to account for start lines
one less than expected for zero length hunk ranges.

[1]: http://www.artima.com/weblogs/viewpost.jsp?thread=164293

import os, sys, textwrap
# import from the live mercurial repo
sys.path.insert(0, "..")
# fall back to pure modules if required C extensions are not available
sys.path.append(os.path.join('..', 'mercurial', 'pure'))
from mercurial import demandimport; demandimport.enable()
from mercurial import encoding
from mercurial.commands import table, globalopts
from mercurial.i18n import _
from mercurial.help import helptable
from mercurial import extensions
from mercurial import util

def get_desc(docstr):
    if not docstr:
        return "", ""
    # sanitize
    docstr = docstr.strip("\n")
    docstr = docstr.rstrip()
    shortdesc = docstr.splitlines()[0].strip()

    i = docstr.find("\n")
    if i != -1:
        desc = docstr[i + 2:]
    else:
        desc = shortdesc

    desc = textwrap.dedent(desc)

    return (shortdesc, desc)

def get_opts(opts):
    for opt in opts:
        if len(opt) == 5:
            shortopt, longopt, default, desc, optlabel = opt
        else:
            shortopt, longopt, default, desc = opt
        allopts = []
        if shortopt:
            allopts.append("-%s" % shortopt)
        if longopt:
            allopts.append("--%s" % longopt)
        desc += default and _(" (default: %s)") % default or ""
        yield (", ".join(allopts), desc)

def get_cmd(cmd, cmdtable):
    d = {}
    attr = cmdtable[cmd]
    cmds = cmd.lstrip("^").split("|")

    d['cmd'] = cmds[0]
    d['aliases'] = cmd.split("|")[1:]
    d['desc'] = get_desc(attr[0].__doc__)
    d['opts'] = list(get_opts(attr[1]))

    s = 'hg ' + cmds[0]
    if len(attr) > 2:
        if not attr[2].startswith('hg'):
            s += ' ' + attr[2]
        else:
            s = attr[2]
    d['synopsis'] = s.strip()

    return d

def section(ui, s):
    ui.write("%s\n%s\n\n" % (s, "-" * encoding.colwidth(s)))

def subsection(ui, s):
    ui.write("%s\n%s\n\n" % (s, '"' * encoding.colwidth(s)))

def subsubsection(ui, s):
    ui.write("%s\n%s\n\n" % (s, "." * encoding.colwidth(s)))

def subsubsubsection(ui, s):
    ui.write("%s\n%s\n\n" % (s, "#" * encoding.colwidth(s)))


def show_doc(ui):
    # print options
    section(ui, _("Options"))
    for optstr, desc in get_opts(globalopts):
        ui.write("%s\n    %s\n\n" % (optstr, desc))

    # print cmds
    section(ui, _("Commands"))
    commandprinter(ui, table, subsection)

    # print topics
    for names, sec, doc in helptable:
        if names[0] == "config":
            # The config help topic is included in the hgrc.5 man
            # page.
            continue
        for name in names:
            ui.write(".. _%s:\n" % name)
        ui.write("\n")
        section(ui, sec)
        if util.safehasattr(doc, '__call__'):
            doc = doc()
        ui.write(doc)
        ui.write("\n")

    section(ui, _("Extensions"))
    ui.write(_("This section contains help for extensions that are distributed "
               "together with Mercurial. Help for other extensions is available "
               "in the help system."))
    ui.write("\n\n"
             ".. contents::\n"
             "   :class: htmlonly\n"
             "   :local:\n"
             "   :depth: 1\n\n")

    for extensionname in sorted(allextensionnames()):
        mod = extensions.load(None, extensionname, None)
        subsection(ui, extensionname)
        ui.write("%s\n\n" % mod.__doc__)
        cmdtable = getattr(mod, 'cmdtable', None)
        if cmdtable:
            subsubsection(ui, _('Commands'))
            commandprinter(ui, cmdtable, subsubsubsection)

def commandprinter(ui, cmdtable, sectionfunc):
    h = {}
    for c, attr in cmdtable.items():
        f = c.split("|")[0]
        f = f.lstrip("^")
        h[f] = c
    cmds = h.keys()
    cmds.sort()

    for f in cmds:
        if f.startswith("debug"):
            continue
        d = get_cmd(h[f], cmdtable)
        sectionfunc(ui, d['cmd'])
        # synopsis
        ui.write("::\n\n")
        synopsislines = d['synopsis'].splitlines()
        for line in synopsislines:
            # some commands (such as rebase) have a multi-line
            # synopsis
            ui.write("   %s\n" % line)
        ui.write('\n')
        # description
        ui.write("%s\n\n" % d['desc'][1])
        # options
        opt_output = list(d['opts'])
        if opt_output:
            opts_len = max([len(line[0]) for line in opt_output])
            ui.write(_("Options:\n\n"))
            for optstr, desc in opt_output:
                if desc:
                    s = "%-*s  %s" % (opts_len, optstr, desc)
                else:
                    s = optstr
                ui.write("%s\n" % s)
            ui.write("\n")
        # aliases
        if d['aliases']:
            ui.write(_("    aliases: %s\n\n") % " ".join(d['aliases']))


def allextensionnames():
    return extensions.enabled().keys() + extensions.disabled().keys()

if __name__ == "__main__":
    show_doc(sys.stdout)