luarocks test: add --prepare flag (#1314)

* Added prepare flag in test command
* Added test for prepare flag in spec/test_spec.lua

Fixes #1303

2 files changed, 11 insertions, 6 deletions

diff --git a/src/luarocks/cmd/test.lua b/src/luarocks/cmd/test.lua
index 21838c90..be9a5dfb 100644
--- a/src/luarocks/cmd/test.lua
+++ b/src/luarocks/cmd/test.lua
@@ -23,7 +23,8 @@ to separate LuaRocks arguments from test suite arguments.]],
       :args("?")
    cmd:argument("args", "Test suite arguments.")
       :args("*")
-
+   cmd:flag("--prepare", "Only install dependencies needed for testing only, but do not run the test")
+   
    cmd:option("--test-type", "Specify the test suite type manually if it was "..
       "not specified in the rockspec and it could not be auto-detected.")
       :argname("<type>")
@@ -31,7 +32,7 @@ end
 
 function cmd_test.command(args)
    if args.rockspec and args.rockspec:match("rockspec$") then
-      return test.run_test_suite(args.rockspec, args.test_type, args.args)
+      return test.run_test_suite(args.rockspec, args.test_type, args.args, args.prepare)
    end
 
    table.insert(args.args, 1, args.rockspec)
@@ -40,8 +41,8 @@ function cmd_test.command(args)
    if not rockspec then
       return nil, err
    end
-
-   return test.run_test_suite(rockspec, args.test_type, args.args)
+   
+   return test.run_test_suite(rockspec, args.test_type, args.args, args.prepare)
 end
 
 return cmd_test
diff --git a/src/luarocks/test.lua b/src/luarocks/test.lua
index 15eca234..cf475fd3 100644
--- a/src/luarocks/test.lua
+++ b/src/luarocks/test.lua
@@ -33,7 +33,7 @@ local function get_test_type(rockspec)
 end
 
 -- Run test suite as configured in rockspec in the current directory.
-function test.run_test_suite(rockspec_arg, test_type, args)
+function test.run_test_suite(rockspec_arg, test_type, args, prepare)
    local rockspec
    if type(rockspec_arg) == "string" then
       local err, errcode
@@ -68,7 +68,11 @@ function test.run_test_suite(rockspec_arg, test_type, args)
       return nil, "failed loading test execution module " .. mod_name
    end
 
-   return test_mod.run_tests(rockspec.test, args)
+   if prepare then
+      return test_mod.run_tests(rockspec_arg, {"--version"})
+   else
+      return test_mod.run_tests(rockspec.test, args)
+   end
 end
 
 return test