git-mergetool: move show_tool_help to mergetool--lib

This is the first step in unifying "git difftool --tool-help" and
"git mergetool --tool-help".

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-mergetool: remove redundant assignment

TOOL_MODE is set at the top of git-mergetool.sh so there is no need to
set it again in show_tool_help.  Removing this lets us re-use
show_tool_help in git-difftool.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-mergetool: don't hardcode 'mergetool' in show_tool_help

When using show_tool_help from git-difftool we will want it to print
"git difftool" not "git mergetool" so use "git ${TOOL_MODE}tool".

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
git-difftool: use git-mergetool--lib for "--tool-help"

The "--tool-help" option to git-difftool currently displays incorrect
output since it uses the names of the files in
"$GIT_EXEC_PATH/mergetools/" rather than the list of command names in
git-mergetool--lib.

Fix this by simply delegating the "--tool-help" argument to the
show_tool_help function in git-mergetool--lib.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetools: support TortoiseGitMerge

TortoiseMerge.exe was ben renamed to TortoiseGitMerge.exe (starting
with 1.8.0) in order to make it clear that it has special support
for git, and prevent confusion with the TortoiseSVN TortoiseMerge
version.

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetools/vim: remove redundant diff command

vimdiff and vimdiff2 differ only by their merge command so remove the
logic in the diff command since it's not actually needed.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: improve show_tool_help() output

Check the can_diff and can_merge functions before deciding whether
to add the tool to the available/unavailable lists.  This makes
"--tool-help" context-sensitive so that "git mergetool --tool-help"
displays merge tools only and "git difftool --tool-help" displays
diff tools only.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: don't call "exit" in setup_tool

This will make it easier to use setup_tool in places where we expect
that the selected tool will not support the current mode.

We need to introduce a new return code for setup_tool to differentiate
between the case of "the selected tool is invalid" and "the selected
tool is not a built-in" since we must call setup_tool when a custom
'merge.<tool>.path' is configured for a built-in tool but avoid failing
when the configured tool is not a built-in.

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetools: simplify how we handle "vim" and "defaults"

Remove the exceptions for "vim" and "defaults" in the mergetool library
so that every filename in mergetools/ matches 1:1 with the name of a
valid built-in tool.

Define the trivial fallback definition of shell functions in-line in
git-mergetool-lib script, instead of dot-sourcing them from another
file.  The result is much easier to follow.

[jc: squashed in an update from John Keeping as well]

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: simplify command expressions

Update variable assignments to always use $(command "$arg")
in their RHS instead of "$(command "$arg")" as the latter
is harder to read.  Make get_merge_tool_cmd() simpler by
avoiding "echo" and $(command) substitutions completely.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: improve the help text in guess_merge_tool()

This code path is only activated when the user does not have a valid
configured tool.  Add a message to guide new users towards configuring a
default tool.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetools: teach tortoisemerge to handle filenames with SP correctly

TortoiseGitMerge, unlike TortoiseMerge, can be told to handle paths
with spaces in them by using -option "$FILE" (not -option:"$FILE",
which does not work for such paths) syntax.

This change was necessary because of MSYS path mangling [1], the ":"
after the "base" etc. arguments to TortoiseMerge caused the whole
argument instead of just the file name to be quoted in case of file
names with spaces. So TortoiseMerge was passed

    "-base:new file.txt"

instead of

    -base:"new file.txt"

(including the quotes). To work around this, TortoiseGitMerge does not
require the ":" after the arguments anymore which fixes handling file
names with spaces [2] (as written above).

[1] http://www.mingw.org/wiki/Posix_path_conversion
[2] https://github.com/msysgit/msysgit/issues/57

Signed-off-by: Sven Strickroth <email@cs-ware.de>
Reported-by: Sebastian Schuberth <sschuberth@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: add functions for finding available tools

Refactor show_tool_help() so that the tool-finding logic is broken out
into a separate show_tool_names() function.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
mergetool--lib: list user configured tools in '--tool-help'

Signed-off-by: John Keeping <john@keeping.me.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
doc: generate a list of valid merge tools

Use the show_tool_names() function to build lists of all
the built-in tools supported by difftool and mergetool.
This frees us from needing to update the documentation
whenever a new tool is added.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Merge branch 'jk/mergetool' into next

Cleans up mergetool/difftool combo.

* jk/mergetool:
  mergetools: simplify how we handle "vim" and "defaults"
  mergetool--lib: don't call "exit" in setup_tool
  mergetool--lib: improve show_tool_help() output
  mergetools/vim: remove redundant diff command
  git-difftool: use git-mergetool--lib for "--tool-help"
  git-mergetool: don't hardcode 'mergetool' in show_tool_help
  git-mergetool: remove redundant assignment
  git-mergetool: move show_tool_help to mergetool--lib
Merge branch 'da/mergetool-docs' into next

Build on top of the clean-up done by jk/mergetool and automatically
generate the list of mergetool and difftool backends the build
supports to be included in the documentation.

* da/mergetool-docs:
  doc: generate a list of valid merge tools
  mergetool--lib: list user configured tools in '--tool-help'
  mergetool--lib: add functions for finding available tools
  mergetool--lib: improve the help text in guess_merge_tool()
  mergetool--lib: simplify command expressions
Merge branch 'ss/mergetools-tortoise' into next

Update mergetools to work better with newer merge helper tortoise ships.

* ss/mergetools-tortoise:
  mergetools: teach tortoisemerge to handle filenames with SP correctly
  mergetools: support TortoiseGitMerge