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-rw-r--r--src/rebar_config.erl16
-rw-r--r--src/rebar_core.erl3
-rw-r--r--src/rebar_deps.erl49
-rw-r--r--src/rebar_erlc_compiler.erl45
-rw-r--r--src/rebar_eunit.erl171
-rw-r--r--src/rebar_utils.erl40
6 files changed, 228 insertions, 96 deletions
diff --git a/src/rebar_config.erl b/src/rebar_config.erl
index 10c6483..1c90d22 100644
--- a/src/rebar_config.erl
+++ b/src/rebar_config.erl
@@ -39,13 +39,21 @@
-include("rebar.hrl").
+-ifdef(namespaced_types).
+% dict:dict() exists starting from Erlang 17.
+-type rebar_dict() :: dict:dict().
+-else.
+% dict() has been obsoleted in Erlang 17 and deprecated in 18.
+-type rebar_dict() :: dict().
+-endif.
+
-record(config, { dir :: file:filename(),
opts = [] :: list(),
- globals = new_globals() :: dict(),
- envs = new_env() :: dict(),
+ globals = new_globals() :: rebar_dict(),
+ envs = new_env() :: rebar_dict(),
%% cross-directory/-command config
- skip_dirs = new_skip_dirs() :: dict(),
- xconf = new_xconf() :: dict() }).
+ skip_dirs = new_skip_dirs() :: rebar_dict(),
+ xconf = new_xconf() :: rebar_dict() }).
-export_type([config/0]).
diff --git a/src/rebar_core.erl b/src/rebar_core.erl
index 3a4f205..212365b 100644
--- a/src/rebar_core.erl
+++ b/src/rebar_core.erl
@@ -496,8 +496,9 @@ run_modules([Module | Rest], Command, Config, File) ->
{Module, Error}
end.
-apply_hooks(Mode, Config, Command, Env) ->
+apply_hooks(Mode, Config, Command, Env0) ->
Hooks = rebar_config:get_local(Config, Mode, []),
+ Env = rebar_utils:patch_env(Config, Env0),
lists:foreach(fun apply_hook/1,
[{Env, Hook} || Hook <- Hooks,
element(1, Hook) =:= Command orelse
diff --git a/src/rebar_deps.erl b/src/rebar_deps.erl
index 68fb40c..bd94921 100644
--- a/src/rebar_deps.erl
+++ b/src/rebar_deps.erl
@@ -278,7 +278,8 @@ info_help(Description) ->
{app_name, ".*", {svn, "svn://svn.example.org/url"}},
{app_name, ".*", {bzr, "https://www.example.org/url", "Rev"}},
{app_name, ".*", {fossil, "https://www.example.org/url"}},
- {app_name, ".*", {fossil, "https://www.example.org/url", "Vsn"}}]}
+ {app_name, ".*", {fossil, "https://www.example.org/url", "Vsn"}},
+ {app_name, ".*", {p4, "//depot/subdir/app_dir"}}]}
]).
%% Added because of trans deps,
@@ -508,6 +509,40 @@ use_source(Config, Dep, Count) ->
use_source(Config, Dep#dep { dir = TargetDir }, Count-1)
end.
+-record(p4_settings, {
+ client=undefined,
+ transport="tcp4:perforce:1666",
+ username,
+ password
+ }).
+init_p4_settings(Basename) ->
+ #p4_settings{client =
+ case inet:gethostname() of
+ {ok,HostName} ->
+ HostName ++ "-"
+ ++ os:getenv("USER") ++ "-"
+ ++ Basename
+ ++ "-Rebar-automated-download"
+ end}.
+
+download_source(AppDir, {p4, Url}) ->
+ download_source(AppDir, {p4, Url, "#head"});
+download_source(AppDir, {p4, Url, Rev}) ->
+ download_source(AppDir, {p4, Url, Rev, init_p4_settings(filename:basename(AppDir))});
+download_source(AppDir, {p4, Url, _Rev, Settings}) ->
+ ok = filelib:ensure_dir(AppDir),
+ rebar_utils:sh_send("p4 client -i",
+ ?FMT("Client: ~s~n"
+ ++"Description: generated by Rebar~n"
+ ++"Root: ~s~n"
+ ++"View:~n"
+ ++" ~s/... //~s/...~n",
+ [Settings#p4_settings.client,
+ AppDir,
+ Url,
+ Settings#p4_settings.client]),
+ []),
+ rebar_utils:sh(?FMT("p4 -c ~s sync -f", [Settings#p4_settings.client]), []);
download_source(AppDir, {hg, Url, Rev}) ->
ok = filelib:ensure_dir(AppDir),
rebar_utils:sh(?FMT("hg clone -U ~s ~s", [Url, filename:basename(AppDir)]),
@@ -574,6 +609,8 @@ update_source(Config, Dep) ->
Dep
end.
+update_source1(AppDir, Args) when element(1, Args) =:= p4 ->
+ download_source(AppDir, Args);
update_source1(AppDir, {git, Url}) ->
update_source1(AppDir, {git, Url, {branch, "HEAD"}});
update_source1(AppDir, {git, Url, ""}) ->
@@ -697,7 +734,7 @@ source_engine_avail(Source) ->
source_engine_avail(Name, Source)
when Name == hg; Name == git; Name == svn; Name == bzr; Name == rsync;
- Name == fossil ->
+ Name == fossil; Name == p4 ->
case vcs_client_vsn(Name) >= required_vcs_client_vsn(Name) of
true ->
true;
@@ -718,6 +755,7 @@ vcs_client_vsn(Path, VsnArg, VsnRegex) ->
false
end.
+required_vcs_client_vsn(p4) -> {2013, 1};
required_vcs_client_vsn(hg) -> {1, 1};
required_vcs_client_vsn(git) -> {1, 5};
required_vcs_client_vsn(bzr) -> {2, 0};
@@ -725,6 +763,9 @@ required_vcs_client_vsn(svn) -> {1, 6};
required_vcs_client_vsn(rsync) -> {2, 0};
required_vcs_client_vsn(fossil) -> {1, 0}.
+vcs_client_vsn(p4) ->
+ vcs_client_vsn(rebar_utils:find_executable("p4"), " -V",
+ "Rev\\. .*/(\\d+)\\.(\\d)/");
vcs_client_vsn(hg) ->
vcs_client_vsn(rebar_utils:find_executable("hg"), " --version",
"version (\\d+).(\\d+)");
@@ -744,6 +785,8 @@ vcs_client_vsn(fossil) ->
vcs_client_vsn(rebar_utils:find_executable("fossil"), " version",
"version (\\d+).(\\d+)").
+has_vcs_dir(p4, _) ->
+ true;
has_vcs_dir(git, Dir) ->
filelib:is_dir(filename:join(Dir, ".git"));
has_vcs_dir(hg, Dir) ->
@@ -761,6 +804,8 @@ has_vcs_dir(_, _) ->
print_source(#dep{app=App, source=Source}) ->
?CONSOLE("~s~n", [format_source(App, Source)]).
+format_source(App, {p4, Url}) ->
+ format_source(App, {p4, Url, "#head"});
format_source(App, {git, Url}) ->
?FMT("~p BRANCH ~s ~s", [App, "HEAD", Url]);
format_source(App, {git, Url, ""}) ->
diff --git a/src/rebar_erlc_compiler.erl b/src/rebar_erlc_compiler.erl
index b797137..16a7a35 100644
--- a/src/rebar_erlc_compiler.erl
+++ b/src/rebar_erlc_compiler.erl
@@ -47,6 +47,14 @@
info = {[], []} :: erlc_info()
}).
+-ifdef(namespaced_types).
+% digraph:digraph() exists starting from Erlang 17.
+-type rebar_digraph() :: digraph:digraph().
+-else.
+% digraph() has been obsoleted in Erlang 17 and deprecated in 18.
+-type rebar_digraph() :: digraph().
+-endif.
+
%% ===================================================================
%% Public API
%% ===================================================================
@@ -111,8 +119,7 @@ clean(Config, _AppFile) ->
YrlFiles = rebar_utils:find_files("src", "^.*\\.[x|y]rl\$"),
rebar_file_utils:delete_each(
- [ binary_to_list(iolist_to_binary(re:replace(F, "\\.[x|y]rl$", ".erl")))
- || F <- YrlFiles ]),
+ [re:replace(F, "\\.[xy]rl$", ".erl", [{return,list}]) || F <- YrlFiles]),
%% Delete the build graph, if any
rebar_file_utils:rm_rf(erlcinfo_file(Config)),
@@ -141,11 +148,9 @@ test_compile(Config, Cmd, OutDir) ->
%% in src but in a subdirectory of src. Cover only looks in cwd and ../src
%% for source files. Also copy files from src_dirs.
SrcDirs = rebar_utils:src_dirs(proplists:append_values(src_dirs, ErlOpts1)),
- SrcErls = lists:foldl(
- fun(Dir, Acc) ->
- Files = rebar_utils:find_files(Dir, ".*\\.erl\$"),
- lists:append(Acc, Files)
- end, [], SrcDirs),
+ SrcErls = lists:flatmap(
+ fun (Dir) -> rebar_utils:find_files(Dir, ".*\\.erl$") end,
+ SrcDirs),
%% If it is not the first time rebar eunit or rebar qc is executed,
%% there will be source files already present in OutDir. Since some
@@ -156,17 +161,17 @@ test_compile(Config, Cmd, OutDir) ->
%% rebar_file_utils:cp_r.
%% Get the full path to a file that was previously copied in OutDir
- ToCleanUp = fun(F, Acc) ->
+ ToCleanUp = fun(F) ->
F2 = filename:basename(F),
F3 = filename:join([OutDir, F2]),
case filelib:is_regular(F3) of
- true -> [F3|Acc];
- false -> Acc
+ true -> F3;
+ false -> []
end
end,
- ok = rebar_file_utils:delete_each(lists:foldl(ToCleanUp, [], TestErls)),
- ok = rebar_file_utils:delete_each(lists:foldl(ToCleanUp, [], SrcErls)),
+ ok = rebar_file_utils:delete_each(lists:flatmap(ToCleanUp, TestErls)),
+ ok = rebar_file_utils:delete_each(lists:flatmap(ToCleanUp, SrcErls)),
ok = rebar_file_utils:cp_r(SrcErls ++ TestErls, OutDir),
@@ -409,17 +414,17 @@ init_erlcinfo(Config, Erls) ->
update_erlcinfo(G, Source, Dirs) ->
case digraph:vertex(G, Source) of
{_, LastUpdated} ->
- LastModified = filelib:last_modified(Source),
- if LastModified == 0 ->
+ case filelib:last_modified(Source) of
+ 0 ->
%% The file doesn't exist anymore,
%% erase it from the graph.
%% All the edges will be erased automatically.
digraph:del_vertex(G, Source),
modified;
- LastUpdated < LastModified ->
- modify_erlcinfo(G, Source, Dirs);
+ LastModified when LastUpdated < LastModified ->
+ modify_erlcinfo(G, Source, Dirs),
modified;
- true ->
+ _ ->
unmodified
end;
false ->
@@ -522,19 +527,19 @@ expand_file_names(Files, Dirs) ->
end
end, Files).
--spec get_parents(digraph(), file:filename()) -> [file:filename()].
+-spec get_parents(rebar_digraph(), file:filename()) -> [file:filename()].
get_parents(G, Source) ->
%% Return all files which the Source depends upon.
digraph_utils:reachable_neighbours([Source], G).
--spec get_children(digraph(), file:filename()) -> [file:filename()].
+-spec get_children(rebar_digraph(), file:filename()) -> [file:filename()].
get_children(G, Source) ->
%% Return all files dependent on the Source.
digraph_utils:reaching_neighbours([Source], G).
-spec internal_erl_compile(rebar_config:config(), file:filename(),
file:filename(), list(),
- digraph()) -> 'ok' | 'skipped'.
+ rebar_digraph()) -> 'ok' | 'skipped'.
internal_erl_compile(Config, Source, OutDir, ErlOpts, G) ->
%% Determine the target name and includes list by inspecting the source file
Module = filename:basename(Source, ".erl"),
diff --git a/src/rebar_eunit.erl b/src/rebar_eunit.erl
index d969f96..8532af1 100644
--- a/src/rebar_eunit.erl
+++ b/src/rebar_eunit.erl
@@ -155,12 +155,10 @@ run_eunit(Config, CodePath, SrcErls) ->
[filename:rootname(N) ++ "_tests.beam" || N <- AllBeamFiles],
ModuleBeamFiles = randomize_suites(Config, BeamFiles ++ OtherBeamFiles),
- %% Get modules to be run in eunit
+ %% Get matching tests and modules
AllModules = [rebar_utils:beam_to_mod(?EUNIT_DIR, N) || N <- AllBeamFiles],
- {SuitesProvided, FilteredModules} = filter_suites(Config, AllModules),
-
- %% Get matching tests
- Tests = get_tests(Config, SuitesProvided, ModuleBeamFiles, FilteredModules),
+ {Tests, CoverageModules} =
+ get_tests_and_modules(Config, ModuleBeamFiles, AllModules),
SrcModules = [rebar_utils:erl_to_mod(M) || M <- SrcErls],
@@ -169,7 +167,7 @@ run_eunit(Config, CodePath, SrcErls) ->
StatusBefore = status_before_eunit(),
EunitResult = perform_eunit(Config, Tests),
- perform_cover(Config, FilteredModules, SrcModules),
+ perform_cover(Config, CoverageModules, SrcModules),
cover_close(CoverLog),
case proplists:get_value(reset_after_eunit, get_eunit_opts(Config),
@@ -214,18 +212,23 @@ setup_code_path() ->
CodePath.
%%
-%% == filter suites ==
+%% == get matching tests ==
%%
+get_tests_and_modules(Config, ModuleBeamFiles, AllModules) ->
+ SelectedSuites = get_selected_suites(Config, AllModules),
+ {Tests, QualifiedTests} = get_qualified_and_unqualified_tests(Config),
+ Modules = get_test_modules(SelectedSuites, Tests,
+ QualifiedTests, ModuleBeamFiles),
+ CoverageModules = get_coverage_modules(AllModules, Modules, QualifiedTests),
+ MatchedTests = get_matching_tests(Modules, Tests, QualifiedTests),
+ {MatchedTests, CoverageModules}.
-filter_suites(Config, Modules) ->
+%%
+%% == get suites specified via 'suites' option ==
+%%
+get_selected_suites(Config, Modules) ->
RawSuites = get_suites(Config),
- SuitesProvided = RawSuites =/= "",
Suites = [list_to_atom(Suite) || Suite <- string:tokens(RawSuites, ",")],
- {SuitesProvided, filter_suites1(Modules, Suites)}.
-
-filter_suites1(Modules, []) ->
- Modules;
-filter_suites1(Modules, Suites) ->
[M || M <- Suites, lists:member(M, Modules)].
get_suites(Config) ->
@@ -236,6 +239,32 @@ get_suites(Config) ->
Suites
end.
+get_qualified_and_unqualified_tests(Config) ->
+ RawFunctions = rebar_utils:get_experimental_global(Config, tests, ""),
+ FunctionNames = [FunctionName ||
+ FunctionName <- string:tokens(RawFunctions, ",")],
+ get_qualified_and_unqualified_tests1(FunctionNames, [], []).
+
+get_qualified_and_unqualified_tests1([], Functions, QualifiedFunctions) ->
+ {Functions, QualifiedFunctions};
+get_qualified_and_unqualified_tests1([TestName|TestNames], Functions,
+ QualifiedFunctions) ->
+ case string:tokens(TestName, ":") of
+ [TestName] ->
+ Function = list_to_atom(TestName),
+ get_qualified_and_unqualified_tests1(
+ TestNames, [Function|Functions], QualifiedFunctions);
+ [ModuleName, FunctionName] ->
+ M = list_to_atom(ModuleName),
+ F = list_to_atom(FunctionName),
+ get_qualified_and_unqualified_tests1(TestNames, Functions,
+ [{M, F}|QualifiedFunctions]);
+ _ ->
+ ?ABORT("Unsupported test function specification: ~s~n", [TestName])
+ end.
+
+%% Provide modules which are to be searched for tests.
+%% Several scenarios are possible:
%%
%% == randomize suites ==
%%
@@ -265,60 +294,66 @@ randomize_suites1(Modules, Seed) ->
%%
%% == get matching tests ==
+%% 1) Specific tests have been provided and/or
+%% no unqualified tests have been specified and
+%% there were some qualified tests, then we can search for
+%% functions in specified suites (or in empty set of suites).
%%
-get_tests(Config, SuitesProvided, ModuleBeamFiles, FilteredModules) ->
- Modules = case SuitesProvided of
- false ->
- %% No specific suites have been provided, use
- %% ModuleBeamFiles which filters out "*_tests" modules
- %% so eunit won't doubly run them and cover only
- %% calculates coverage on production code. However,
- %% keep "*_tests" modules that are not automatically
- %% included by eunit.
- %%
- %% From 'Primitives' in the EUnit User's Guide
- %% http://www.erlang.org/doc/apps/eunit/chapter.html
- %% "In addition, EUnit will also look for another
- %% module whose name is ModuleName plus the suffix
- %% _tests, and if it exists, all the tests from that
- %% module will also be added. (If ModuleName already
- %% contains the suffix _tests, this is not done.) E.g.,
- %% the specification {module, mymodule} will run all
- %% tests in the modules mymodule and mymodule_tests.
- %% Typically, the _tests module should only contain
- %% test cases that use the public interface of the main
- %% module (and no other code)."
- [rebar_utils:beam_to_mod(?EUNIT_DIR, N) ||
- N <- ModuleBeamFiles];
- true ->
- %% Specific suites have been provided, return the
- %% filtered modules
- FilteredModules
- end,
- get_matching_tests(Config, Modules).
-
-get_tests(Config) ->
- case rebar_config:get_global(Config, tests, "") of
- "" ->
- rebar_config:get_global(Config, test, "");
- Suites ->
- Suites
+%% 2) Neither specific suites nor qualified test names have been
+%% provided use ModuleBeamFiles which filters out "*_tests"
+%% modules so EUnit won't doubly run them and cover only
+%% calculates coverage on production code. However,
+%% keep "*_tests" modules that are not automatically
+%% included by EUnit.
+%%
+%% From 'Primitives' in the EUnit User's Guide
+%% http://www.erlang.org/doc/apps/eunit/chapter.html
+%% "In addition, EUnit will also look for another
+%% module whose name is ModuleName plus the suffix
+%% _tests, and if it exists, all the tests from that
+%% module will also be added. (If ModuleName already
+%% contains the suffix _tests, this is not done.) E.g.,
+%% the specification {module, mymodule} will run all
+%% tests in the modules mymodule and mymodule_tests.
+%% Typically, the _tests module should only contain
+%% test cases that use the public interface of the main
+%% module (and no other code)."
+get_test_modules(SelectedSuites, Tests, QualifiedTests, ModuleBeamFiles) ->
+ SuitesProvided = SelectedSuites =/= [],
+ OnlyQualifiedTestsProvided = QualifiedTests =/= [] andalso Tests =:= [],
+ if
+ SuitesProvided orelse OnlyQualifiedTestsProvided ->
+ SelectedSuites;
+ true ->
+ [rebar_utils:beam_to_mod(?EUNIT_DIR, N) ||
+ N <- ModuleBeamFiles]
end.
-get_matching_tests(Config, Modules) ->
- RawFunctions = get_tests(Config),
- Tests = [list_to_atom(F1) || F1 <- string:tokens(RawFunctions, ",")],
- case Tests of
- [] ->
- Modules;
- Functions ->
- case get_matching_tests1(Modules, Functions, []) of
- [] ->
- [];
- RawTests ->
- make_test_primitives(RawTests)
- end
- end.
+get_coverage_modules(AllModules, Modules, QualifiedTests) ->
+ ModuleFilterMapper =
+ fun({M, _}) ->
+ case lists:member(M, AllModules) of
+ true -> {true, M};
+ _-> false
+ end
+ end,
+ ModulesFromQualifiedTests = lists:zf(ModuleFilterMapper, QualifiedTests),
+ lists:usort(Modules ++ ModulesFromQualifiedTests).
+
+get_matching_tests(Modules, [], []) ->
+ Modules;
+get_matching_tests(Modules, [], QualifiedTests) ->
+ FilteredQualifiedTests = filter_qualified_tests(Modules, QualifiedTests),
+ lists:merge(Modules, make_test_primitives(FilteredQualifiedTests));
+get_matching_tests(Modules, Tests, QualifiedTests) ->
+ AllTests = lists:merge(QualifiedTests,
+ get_matching_tests1(Modules, Tests, [])),
+ make_test_primitives(AllTests).
+
+filter_qualified_tests(Modules, QualifiedTests) ->
+ TestsFilter = fun({Module, _Function}) ->
+ lists:all(fun(M) -> M =/= Module end, Modules) end,
+ lists:filter(TestsFilter, QualifiedTests).
get_matching_tests1([], _Functions, TestFunctions) ->
TestFunctions;
@@ -608,9 +643,9 @@ align_notcovered_count(Module, Covered, NotCovered, true) ->
cover_write_index(Coverage, SrcModules) ->
{ok, F} = file:open(filename:join([?EUNIT_DIR, "index.html"]), [write]),
ok = file:write(F, "<!DOCTYPE HTML><html>\n"
- "<head><meta charset=\"utf-8\">"
- "<title>Coverage Summary</title></head>\n"
- "<body>\n"),
+ "<head><meta charset=\"utf-8\">"
+ "<title>Coverage Summary</title></head>\n"
+ "<body>\n"),
IsSrcCoverage = fun({Mod,_C,_N}) -> lists:member(Mod, SrcModules) end,
{SrcCoverage, TestCoverage} = lists:partition(IsSrcCoverage, Coverage),
cover_write_index_section(F, "Source", SrcCoverage),
diff --git a/src/rebar_utils.erl b/src/rebar_utils.erl
index 517ac33..fa35fed 100644
--- a/src/rebar_utils.erl
+++ b/src/rebar_utils.erl
@@ -31,6 +31,7 @@
get_arch/0,
wordsize/0,
sh/2,
+ sh_send/3,
find_files/2, find_files/3,
now_str/0,
ensure_dir/1,
@@ -53,7 +54,8 @@
src_dirs/1,
ebin_dir/0,
base_dir/1,
- processing_base_dir/1, processing_base_dir/2]).
+ processing_base_dir/1, processing_base_dir/2,
+ patch_env/2]).
-include("rebar.hrl").
@@ -87,6 +89,24 @@ wordsize() ->
integer_to_list(8 * erlang:system_info(wordsize))
end.
+sh_send(Command0, String, Options0) ->
+ ?INFO("sh_send info:\n\tcwd: ~p\n\tcmd: ~s < ~s\n", [get_cwd(), Command0, String]),
+ ?DEBUG("\topts: ~p\n", [Options0]),
+
+ DefaultOptions = [use_stdout, abort_on_error],
+ Options = [expand_sh_flag(V)
+ || V <- proplists:compact(Options0 ++ DefaultOptions)],
+
+ Command = patch_on_windows(Command0, proplists:get_value(env, Options, [])),
+ PortSettings = proplists:get_all_values(port_settings, Options) ++
+ [exit_status, {line, 16384}, use_stdio, stderr_to_stdout, hide],
+ Port = open_port({spawn, Command}, PortSettings),
+
+ %% allow us to send some data to the shell command's STDIN
+ %% Erlang doesn't let us get any reply after sending an EOF, though...
+ Port ! {self(), {command, String}},
+ port_close(Port).
+
%%
%% Options = [Option] -- defaults to [use_stdout, abort_on_error]
%% Option = ErrorOption | OutputOption | {cd, string()} | {env, Env}
@@ -319,6 +339,23 @@ processing_base_dir(Config, Dir) ->
AbsDir = filename:absname(Dir),
AbsDir =:= base_dir(Config).
+%% @doc Returns the list of environment variables including 'REBAR' which points to the
+%% rebar executable used to execute the currently running command. The environment is
+%% not modified if rebar was invoked programmatically.
+-spec patch_env(rebar_config:config(), [{string(), string()}]) -> [{string(), string()}].
+patch_env(Config, []) ->
+ % if we reached an empty list the env did not contain the REBAR variable
+ case rebar_config:get_xconf(Config, escript, "") of
+ "" -> % rebar was invoked programmatically
+ [];
+ Path ->
+ [{"REBAR", Path}]
+ end;
+patch_env(_Config, [{"REBAR", _} | _]=All) ->
+ All;
+patch_env(Config, [E | Rest]) ->
+ [E | patch_env(Config, Rest)].
+
%% ====================================================================
%% Internal functions
%% ====================================================================
@@ -480,6 +517,7 @@ vcs_vsn_1(Vcs, Dir) ->
end.
vcs_vsn_cmd(git) -> "git describe --always --tags";
+vcs_vsn_cmd(p4) -> "echo #head";
vcs_vsn_cmd(hg) -> "hg identify -i";
vcs_vsn_cmd(bzr) -> "bzr revno";
vcs_vsn_cmd(svn) -> "svnversion";