allow plugins to have a help file

cmd/micro/help.go

@@ -1,5 +1,9 @@
 package main
 
+import (
+	"io/ioutil"
+)
+
 type HelpPage interface {
 	HelpFile() ([]byte, error)
 }
@@ -19,3 +23,16 @@ type assetHelpPage string
 func (file assetHelpPage) HelpFile() ([]byte, error) {
 	return Asset("runtime/help/" + string(file) + ".md")
 }
+
+type fileHelpPage string
+
+func (file fileHelpPage) HelpFile() ([]byte, error) {
+	return ioutil.ReadFile(string(file))
+}
+
+func AddPluginHelp(name, file string) {
+	if _, exists := helpPages[name]; exists {
+		return
+	}
+	helpPages[name] = fileHelpPage(file)
+}

cmd/micro/plugin.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strings"
 
 	"github.com/layeh/gopher-luar"
@@ -126,8 +127,9 @@ func LoadPlugins() {
 			pluginName := plugin.Name()
 			files, _ := ioutil.ReadDir(configDir + "/plugins/" + pluginName)
 			for _, f := range files {
+				fullPath := filepath.Join(configDir, "plugins", pluginName, f.Name())
 				if f.Name() == pluginName+".lua" {
-					data, _ := ioutil.ReadFile(configDir + "/plugins/" + pluginName + "/" + f.Name())
+					data, _ := ioutil.ReadFile(fullPath)
 					pluginDef := "\nlocal P = {}\n" + pluginName + " = P\nsetmetatable(" + pluginName + ", {__index = _G})\nsetfenv(1, P)\n"
 
 					if err := L.DoString(pluginDef + string(data)); err != nil {
@@ -135,6 +137,8 @@ func LoadPlugins() {
 						continue
 					}
 					loadedPlugins = append(loadedPlugins, pluginName)
+				} else if f.Name() == "help.md" {
+					AddPluginHelp(pluginName, fullPath)
 				}
 			}
 		}

runtime/help/plugins.md

@@ -4,6 +4,8 @@ Micro supports creating plugins with a simple Lua system. Every plugin has a
 main script which is run at startup which should be placed in 
 `~/.config/micro/plugins/pluginName/pluginName.lua`.
 
+If you want to add a help page for your plugin, place a markdown file in `~/.config/micro/plugins/pluginName/help.md`. 
+
 There are a number of callback functions which you can create in your
 plugin to run code at times other than startup. The naming scheme is
 `onAction(view)`. For example a function which is run every time the user saves