Add support for build-only dependencies

Adds the `build_dependencies` key to the rockspec format,
for dependencies that are only triggered when building from
source (e.g. via `luarocks build` or running `luarocks install`
on a rockspec) and not when building from a packaged `.rock`
file using `luarocks install`.

6 files changed, 49 insertions, 31 deletions

diff --git a/src/luarocks/build.lua b/src/luarocks/build.lua
index c08fa6c6..c9e36d89 100644
--- a/src/luarocks/build.lua
+++ b/src/luarocks/build.lua
@@ -173,18 +173,25 @@ function build.build_rockspec(rockspec_file, need_to_fetch, minimal_mode, deps_m
       return nil, "Rockspec error: build type not specified"
    end
 
-   local ok
-   if not build_only_deps then
-      ok, err, errcode = deps.check_external_deps(rockspec, "build")
-      if err then
-         return nil, err, errcode
-      end
-   end
-
    if deps_mode == "none" then
       util.warning("skipping dependency checks.")
    else
-      local ok, err, errcode = deps.fulfill_dependencies(rockspec, deps_mode)
+
+      if not build_only_deps then
+         local ok, err, errcode = deps.check_external_deps(rockspec, "build")
+         if err then
+            return nil, err, errcode
+         end
+
+         if next(rockspec.build_dependencies) then
+            local ok, err, errcode = deps.fulfill_dependencies(rockspec, "build_dependencies", deps_mode)
+            if err then
+               return nil, err, errcode
+            end
+         end
+      end
+
+      local ok, err, errcode = deps.fulfill_dependencies(rockspec, "dependencies", deps_mode)
       if err then
          return nil, err, errcode
       end
diff --git a/src/luarocks/cmd/build.lua b/src/luarocks/cmd/build.lua
index 1b5c8fdc..0a408fb4 100644
--- a/src/luarocks/cmd/build.lua
+++ b/src/luarocks/cmd/build.lua
@@ -8,7 +8,6 @@ local path = require("luarocks.path")
 local util = require("luarocks.util")
 local fetch = require("luarocks.fetch")
 local fs = require("luarocks.fs")
-local dir = require("luarocks.dir")
 local deps = require("luarocks.deps")
 local remove = require("luarocks.remove")
 local cfg = require("luarocks.core.cfg")
diff --git a/src/luarocks/cmd/install.lua b/src/luarocks/cmd/install.lua
index 80fc4d27..c1d9ccc7 100644
--- a/src/luarocks/cmd/install.lua
+++ b/src/luarocks/cmd/install.lua
@@ -12,7 +12,6 @@ local writer = require("luarocks.manif.writer")
 local remove = require("luarocks.remove")
 local search = require("luarocks.search")
 local queries = require("luarocks.queries")
-local vers = require("luarocks.core.vers")
 local cfg = require("luarocks.core.cfg")
 
 install.help_summary = "Install a rock."
@@ -89,7 +88,7 @@ function install.install_binary_rock(rock_file, deps_mode, namespace)
    end
 
    if deps_mode ~= "none" then
-      ok, err, errcode = deps.fulfill_dependencies(rockspec, deps_mode)
+      ok, err, errcode = deps.fulfill_dependencies(rockspec, "dependencies", deps_mode)
       if err then return nil, err, errcode end
    end
 
@@ -137,7 +136,7 @@ function install.install_binary_rock_deps(rock_file, deps_mode)
       return nil, "Failed loading rockspec for installed package: "..err, errcode
    end
 
-   ok, err, errcode = deps.fulfill_dependencies(rockspec, deps_mode)
+   ok, err, errcode = deps.fulfill_dependencies(rockspec, "dependencies", deps_mode)
    if err then return nil, err, errcode end
 
    util.printout()
diff --git a/src/luarocks/deps.lua b/src/luarocks/deps.lua
index ccbced0c..ae15cd5e 100644
--- a/src/luarocks/deps.lua
+++ b/src/luarocks/deps.lua
@@ -124,10 +124,11 @@ end
 -- Packages are installed using the LuaRocks "install" command.
 -- Aborts the program if a dependency could not be fulfilled.
 -- @param rockspec table: A rockspec in table format.
+-- @param depskey table: Rockspec key to fetch to get dependency table.
 -- @return boolean or (nil, string, [string]): True if no errors occurred, or
 -- nil and an error message if any test failed, followed by an optional
 -- error code.
-function deps.fulfill_dependencies(rockspec, deps_mode)
+function deps.fulfill_dependencies(rockspec, depskey, deps_mode)
 
    local search = require("luarocks.search")
    local install = require("luarocks.cmd.install")
@@ -160,11 +161,11 @@ function deps.fulfill_dependencies(rockspec, deps_mode)
       end
    end
 
-   deps.report_missing_dependencies(rockspec.name, rockspec.version, rockspec.dependencies, deps_mode, rockspec.rocks_provided)
+   deps.report_missing_dependencies(rockspec.name, rockspec.version, rockspec[depskey], deps_mode, rockspec.rocks_provided)
 
    local first_missing_dep = true
 
-   for _, dep in ipairs(rockspec.dependencies) do
+   for _, dep in ipairs(rockspec[depskey]) do
       if not match_dep(dep, nil, deps_mode, rockspec.rocks_provided) then
          if first_missing_dep then
             util.printout()
diff --git a/src/luarocks/fetch.lua b/src/luarocks/fetch.lua
index db99c3d5..ce9aaff5 100644
--- a/src/luarocks/fetch.lua
+++ b/src/luarocks/fetch.lua
@@ -180,6 +180,20 @@ function fetch.url_to_base_dir(url)
    return (base:gsub("%.([^.]*)$", known_exts):gsub("%.tar", ""))
 end
 
+local function convert_dependencies(rockspec, key)
+   if rockspec[key] then
+      for i = 1, #rockspec[key] do
+         local parsed, err = queries.from_dep_string(rockspec[key][i])
+         if not parsed then
+            return nil, "Parse error processing dependency '"..rockspec[key][i].."': "..tostring(err)
+         end
+         rockspec[key][i] = parsed
+      end
+   else
+      rockspec[key] = {}
+   end
+end
+
 --- Back-end function that actually loads the local rockspec.
 -- Performs some validation and postprocessing of the rockspec contents.
 -- @param filename string: The local filename of the rockspec file.
@@ -212,10 +226,6 @@ function fetch.load_local_rockspec(filename, quick)
       end
    end
 
-   rockspec.format_is_at_least = function(_, v)
-      return parsed_format >= vers.parse_version(v)
-   end
-
    --- Check if rockspec format version satisfies version requirement.
    -- @param rockspec table: The rockspec table.
    -- @param version string: required version.
@@ -229,6 +239,7 @@ function fetch.load_local_rockspec(filename, quick)
 
    util.platform_overrides(rockspec.build)
    util.platform_overrides(rockspec.dependencies)
+   util.platform_overrides(rockspec.build_dependencies)
    util.platform_overrides(rockspec.external_dependencies)
    util.platform_overrides(rockspec.source)
    util.platform_overrides(rockspec.hooks)
@@ -274,17 +285,9 @@ function fetch.load_local_rockspec(filename, quick)
                               and cfg.rocks_provided_3_0
                               or  cfg.rocks_provided)
 
-   if rockspec.dependencies then
-      for i = 1, #rockspec.dependencies do
-         local parsed, err = queries.from_dep_string(rockspec.dependencies[i])
-         if not parsed then
-            return nil, "Parse error processing dependency '"..rockspec.dependencies[i].."': "..tostring(err)
-         end
-         rockspec.dependencies[i] = parsed
-      end
-   else
-      rockspec.dependencies = {}
-   end
+   convert_dependencies(rockspec, "dependencies")
+   convert_dependencies(rockspec, "build_dependencies")
+
    if not quick then
       path.configure_paths(rockspec)
    end
diff --git a/src/luarocks/type/rockspec.lua b/src/luarocks/type/rockspec.lua
index 214f8e0f..54ce9db8 100644
--- a/src/luarocks/type/rockspec.lua
+++ b/src/luarocks/type/rockspec.lua
@@ -48,6 +48,15 @@ local rockspec_types = {
          },
       },
    },
+   build_dependencies = {
+      _version = "3.0",
+      platforms = {}, -- recursively defined below
+      _any = {
+         _type = "string",
+         _name = "a valid dependency string",
+         _pattern = "%s*([a-zA-Z0-9%.%-%_]*/?[a-zA-Z0-9][a-zA-Z0-9%.%-%_]*)%s*([^/]*)",
+      },
+   },
    supported_platforms = {
       _any = string_1,
    },