Merge pull request zyedidia#3799 from dmaluka/doc-update

Some documentation improvements

Author: dmaluka

runtime/help/keybindings.md

@@ -70,6 +70,13 @@ will execute `InsertTab`. To use `,`, `|` or `&` in an action (as an argument
 to a command, for example), escape it with `\` or wrap it in single or double
 quotes.
 
+If the action has an `onAction` lua callback, for example `onAutocomplete` (see
+`> help plugins`), then the action is only considered successful if the action
+itself succeeded *and* the callback returned true. If there are multiple
+`onAction` callbacks for this action, registered by multiple plugins, then the
+action is only considered successful if the action itself succeeded and all the
+callbacks returned true.
+
 ## Binding commands
 
 You can also bind a key to execute a command in command mode (see
@@ -105,6 +112,48 @@ Now when you press `Ctrl-g`, `help` will appear in the command bar and your
 cursor will be placed after it (note the space in the json that controls the
 cursor placement).
 
+## Binding Lua functions
+
+You can also bind a key to a Lua function provided by a plugin, or by your own
+`~/.config/micro/init.lua`. For example:
+
+```json
+{
+    "Alt-q": "lua:foo.bar"
+}
+```
+
+where `foo` is the name of the plugin and `bar` is the name of the lua function
+in it, e.g.:
+
+```lua
+local micro = import("micro")
+
+function bar(bp)
+    micro.InfoBar():Message("Bar action triggered")
+    return true
+end
+```
+
+See `> help plugins` for more informations on how to write lua functions.
+
+For `~/.config/micro/init.lua` the plugin name is `initlua` (so the keybinding
+in this example would be `"Alt-q": "lua:initlua.bar"`).
+
+The currently active bufpane is passed to the lua function as the argument. If
+the key is a mouse button, e.g. `MouseLeft` or `MouseWheelUp`, the mouse event
+info is passed to the lua function as the second argument, of type
+`*tcell.EventMouse`. See https://pkg.go.dev/github.com/micro-editor/tcell/v2#EventMouse
+for the description of this type and its methods.
+
+The return value of the lua function defines whether the action has succeeded.
+This is used when chaining lua functions with other actions. They can be chained
+the same way as regular actions as described above, for example:
+
+```
+"Alt-q": "lua:initlua.bar|Quit"
+```
+
 ## Binding raw escape sequences
 
 Only read this section if you are interested in binding keys that aren't on the
@@ -309,6 +358,8 @@ You can also bind some mouse actions (these must be bound to mouse buttons)
 
 ```
 MousePress
+MouseDrag
+MouseRelease
 MouseMultiCursor
 ```
 

runtime/help/plugins.md

@@ -71,13 +71,24 @@ that micro defines:
 
 * `onAction(bufpane)`: runs when `Action` is triggered by the user, where
    `Action` is a bindable action (see `> help keybindings`). A bufpane
-   is passed as input and the function should return a boolean defining
-   whether the view should be relocated after this action is performed.
+   is passed as input. The function should return a boolean defining
+   whether the action was successful, which is used when the action is
+   chained with other actions (see `> help keybindings`) to determine whether
+   the next actions in the chain should be executed or not.
+
+   If the action is a mouse action, e.g. `MousePress`, the mouse event info
+   is passed to the callback as an extra argument of type `*tcell.EventMouse`.
+   See https://pkg.go.dev/github.com/micro-editor/tcell/v2#EventMouse for the
+   description of this type and its methods.
 
 * `preAction(bufpane)`: runs immediately before `Action` is triggered
    by the user. Returns a boolean which defines whether the action should
    be canceled.
 
+   Similarly to `onAction`, if the action is a mouse action, the mouse event
+   info is passed to the callback as an extra argument of type
+   `*tcell.EventMouse`.
+
 * `onRune(bufpane, rune)`: runs when the composed rune has been inserted
 
 * `preRune(bufpane, rune)`: runs before the composed rune will be inserted
@@ -101,9 +112,6 @@ within. This is almost always the current bufpane.
 
 All available actions are listed in the keybindings section of the help.
 
-These functions should also return a boolean specifying whether the bufpane
-should be relocated to the cursor or not after the action is complete.
-
 ## Accessing micro functions
 
 Some of micro's internal information is exposed in the form of packages, which