Increase reliability (#4)

* Add check to see if commands already exist

* Migrate to go install, as go get will be depricated

* Fix bug in comparison function

* Add installation instructions for $PATH

* remove old stuff

* remove backtick

* complete install

* remove unused function

README.md

@@ -19,6 +19,16 @@ The plugin covers most features required for a gopher.
 
 ## install
 
+make sure the `$GOPATH/bin` path is added to your `$PATH` environment variable. To check this you can run
+```bash
+echo $PATH | grep "$GOPATH/bin"
+```
+
+if nothing shows up, you can add the following to your shell config file
+```bash
+export PATH=$PATH:$GOPATH/bin
+```
+
 add 'ray-x/go.nvim' to your package manager, the dependency is `treesitter` (and optionally, treesitter-objects)
 related binaries will be installed the first time you use it
 Add format in your vimrc.

lua/go.lua

@@ -15,13 +15,16 @@ function go.setup(cfg)
   vim.cmd('command! Gofmt lua require("go.format").gofmt()')
   vim.cmd('command! Goimport lua require("go.format").goimport()')
 
-  vim.cmd([[command GoBuild :setl makeprg=go\ build | :Gmake]])
-  vim.cmd([[command GoGenerate  :setl makeprg=go\ generate | :Gmake]])
-  vim.cmd([[command GoRun       :setl makeprg=go\ run | :Gmake]])
-  vim.cmd([[command GoTestFunc  :Gmake -run ..]])
 
-  vim.cmd([[command GoTest :setl makeprg=go\ test\ ./... | :Gmake]])
-  vim.cmd([[command GoTestCompile  setl makeprg=go\ build | :Gmake]])
+  local cmds = vim.api.nvim_get_commands({})
+
+  if cmds["GoBuild"]       == nil then vim.cmd([[command GoBuild        :setl makeprg=go\ build | :Gmake]]) end
+  if cmds["GoGenerate"]    == nil then vim.cmd([[command GoGenerate     :setl makeprg=go\ generate | :Gmake]]) end
+  if cmds["GoRun"]         == nil then vim.cmd([[command GoRun          :setl makeprg=go\ run | :Gmake]]) end
+  if cmds["GoTestFunc"]    == nil then vim.cmd([[command GoTestFunc     :Gmake -run ..]]) end
+
+  if cmds["GoTest"]        == nil then vim.cmd([[command GoTest         :setl makeprg=go\ test\ ./... | :Gmake]]) end
+  if cmds["GoTestCompile"] == nil then vim.cmd([[command GoTestCompile  :setl makeprg=go\ build | :Gmake]]) end
 
   vim.cmd([[command! GoAddTest lua require("go.gotests").fun_test()]])
   vim.cmd([[command! GoAddExpTest lua require("go.gotests").exported_test()]])

lua/go/install.lua

@@ -1,53 +1,39 @@
 local uv = vim.loop
-local gopath = vim.fn.expand("$GOPATH")
-local gobinpath = gopath .. "/bin/"
+local DIR_SEP = package.config:sub(1,1)
+
 local url = {
-  golines = "segmentio/golines",
-  gofumpt = "mvdan/gofumpt",
-  gofumports = "mvdan/gofumpt",
-  gomodifytags = "fatih/gomodifytags",
-  gotsts = "cweill/gotests",
-  iferr = 'koron/iferr',
-  fillstruct = 'davidrjenni/reftools/cmd/fillstruct',
-  fixplurals = 'davidrjenni/reftools/cmd/fixplurals',
-  fillswitch = 'davidrjenni/reftools/cmd/fillswitch',
+  gofumpt      = "mvdan.cc/gofumpt",
+  gofumports   = "mvdan.cc/gofumpt",
+  golines      = "github.com/segmentio/golines",
+  gomodifytags = "github.com/fatih/gomodifytags",
+  gotsts       = "github.com/cweill/gotests",
+  iferr        = 'github.com/koron/iferr',
+  fillstruct   = 'github.com/davidrjenni/reftools/cmd/fillstruct',
+  fixplurals   = 'github.com/davidrjenni/reftools/cmd/fixplurals',
+  fillswitch   = 'github.com/davidrjenni/reftools/cmd/fillswitch',
 }
 
-local function install(bin)
-  local state = uv.fs_stat(gobinpath .. bin)
-  if not state then
-    print("installing " .. bin)
-    local u = url[bin]
-    if u == nil then
-      print("command " .. bin .. " not supported, please update install.lua")
-      return
-    end
-    u = 'github.com/' .. u
-    local setup = {
-      "go", "get",
-      u
-    }
-    vim.fn.jobstart(
-      setup,
-      -- setup.args,
-      {
-        on_stdout = function(c, data, name)
-          print(data)
+local function is_installed(bin)
+    local env_path = os.getenv("PATH")
+    local base_paths = vim.split(env_path, ":", true)
+
+    for key, value in pairs(base_paths) do
+        if uv.fs_stat(value .. DIR_SEP .. bin) then
+            return true
         end
-      }
-    )
-  end
+    end
+    return false
 end
 
-local function update(bin)
-  local u = url[bin]
+local function go_install(pkg)
+  local u = url[pkg]
   if u == nil then
-    print("command " .. bin .. " not supported, please update install.lua")
+    print("command " .. pkg .. " not supported, please update install.lua, or manually install it")
     return
   end
 
-  u = 'github.com/' .. u
-  local setup = {"go", "get", "-u", u}
+  u = u .. "@latest"
+  local setup = {"go", "install", u}
 
   vim.fn.jobstart(
     setup,
@@ -59,6 +45,17 @@ local function update(bin)
   )
 end
 
+local function install(bin)
+  if not is_installed(bin) then
+    print("installing " .. bin)
+    go_install(bin)
+  end
+end
+
+local function update(bin)
+  go_install(bin)  
+end
+
 local function install_all()
   for key, value in pairs(url) do
     install(key)

lua/go/utils.lua

@@ -1,14 +1,14 @@
 local util = {}
 util.check_same = function(tbl1, tbl2)
   if #tbl1 ~= #tbl2 then
-    return
+    return false
   end
   for k, v in ipairs(tbl1) do
     if v ~= tbl2[k] then
-      return true
+      return false
     end
   end
-  return false
+  return true
 end
 
 util.copy_array = function(from, to)