enable the ability to add local filesystem plugins

lua/dep/fs.lua

@@ -0,0 +1,22 @@
+local h = require('dep.helpers')
+local logger = require('dep.log')
+
+local fs = {}
+
+function fs:sync(package, cb)
+  if not package.exists then
+    fs:link(package, cb)
+  end
+end
+
+function fs:link(package, cb)
+  h.uv.fs_symlink(package.path, package.dir, nil, function(err, _)
+    if err then
+      logger:log("error", "failed to symlink %s; reason: %s", package.id, err)
+    else
+      cb(err)
+    end
+  end)
+end
+
+return fs

lua/dep/package.lua

@@ -17,6 +17,7 @@ local logger = require('dep.log')
 ---@field as string? overrides the short name of the package which is usually set
 --- to a substring of all the chars after '/' in spec[1]
 ---@field url string? the url to the git repository hosting the package
+---@field path string? path to local version of plugin, overrides the url
 ---@field branch string? the branch which the version of the package resides
 ---@field commit string? the commit which the version of the package resides
 ---@field disable boolean? if true disables the package from being loaded
@@ -43,6 +44,7 @@ local logger = require('dep.log')
 ---@field perf table performance metrics for the package
 ---@field name string the name of the package
 ---@field url string the url of the package
+---@field path string? the path of the package which overrides the url
 ---@field branch string the branch of the package
 ---@field dir string the directory of the package
 ---@field commit string the commit of the package
@@ -126,6 +128,13 @@ local function check_spec(spec)
     end
   end
 
+  if spec.path ~= nil then -- spec.path
+    if type(spec.path) ~= "string" then
+      logger:log("spec", "spec.path must be a string in %s", spec[1])
+      return false
+    end
+  end
+
   if spec.branch ~= nil then -- spec.branch
     if type(spec.branch) ~= "string" then
       logger:log("spec", "spec.branch must be a string in %s", spec[1])
@@ -250,6 +259,7 @@ function package:new(spec, overrides)
 
   o.name = spec.as or o.name or id:match("^[%w-_.]+/([%w-_.]+)$")
   o.url = spec.url or o.url or ("https://github.com/"..id..".git")
+  o.path = spec.path and vim.fs.normalize(spec.path) or spec.path
   o.branch = spec.branch or o.branch
   o.dir = base_dir.."/"..o.name
   o.commit = spec.commit