chore: add demos (#118)

* chore: add dataset for demos

* chore(demos): add demos

* chore: update CONTRIBUTING

* this copefully will fix comments gif

CONTRIBUTING.md

···
 
 ### Documentation
 Here we're using [mini.doc](https://github.com/echasnovski/mini.nvim/blob/main/readmes/mini-doc.md)
-for generating help files based on [LuaCats](https://luals.github.io/wiki/annotations/) annotations in comments.
+for generating vimhelp files based on [LuaCats](https://luals.github.io/wiki/annotations/) annotations in comments.
+
+For demo gifs in [readme](./README.md) we're using [vhs](https://github.com/charmbracelet/vhs).
+All files related to demos live in [/vhs](./vhs) dir.
 
 You can generate docs with:
 ```bash
-task docgen
+task docgen       # generates vimhelp
+task vhs:generate # generates demo gifs
 ```
 
 ### Commit messages

README.md

···
     <b>Add and remove tags for structs via <a href="https://github.com/fatih/gomodifytags">gomodifytags</a></b>
   </summary>
 
+  ![Add tags demo](./vhs/tags.gif)
+
   By default `json` tag will be added/removed, if not set:
 
   ```vim
···
     <b>Interface implementation via <a href="https://github.com/josharian/impl">impl<a></b>
   </summary>
 
+  ![Auto interface implementation demo](./vhs/impl.gif)
+
   Syntax of the command:
   ```vim
   :GoImpl [receiver] [interface]
···
     <b>Generate boilerplate for doc comments</b>
   </summary>
 
+  ![Generate comments](./vhs/comment.gif)
+
   First set a cursor on **public** package/function/interface/struct and execute:
 
   ```vim
···
   <summary>
     <b>Generate <code>if err != nil {</code> via <a href="https://github.com/koron/iferr">iferr</a></b>
   </summary>
+
+  ![Generate if err != nil {](./vhs/iferr.gif)
 
   Set the cursor on the line with `err` and execute
 

Taskfile.yml

···
 version: "3"
+
+includes:
+  vhs:
+    taskfile: ./vhs/Taskfile.yml
+    dir: ./vhs
+
 tasks:
   lint:
     cmds:

scripts/minimal_init.lua

···
 install_plug "nvim-lua/plenary.nvim"
 install_plug "nvim-treesitter/nvim-treesitter"
 install_plug "echasnovski/mini.doc" -- used for docs generation
+install_plug "folke/tokyonight.nvim" -- theme for generating demos
 install_plug "echasnovski/mini.test"
 
 vim.env.XDG_CONFIG_HOME = root ".tests/config"
···
 
 vim.opt.runtimepath:append(root())
 vim.opt.packpath:append(root ".tests/site")
+vim.o.swapfile = false
+vim.o.writebackup = false
 vim.notify = vim.print
 
 -- install go treesitter parse
···
       end,
     },
   }
+end
+
+-- set colorscheme only when running ui
+if #vim.api.nvim_list_uis() == 1 then
+  vim.cmd.colorscheme "tokyonight-night"
+  vim.o.cursorline = true
+  vim.o.number = true
 end
 
 -- needed for tests, i dont know the reason why, but on start

vhs/Taskfile.yml

···
+version: "3"
+tasks:
+  generate:
+    deps:
+      - comment
+      - iferr
+      - tags
+      - impl
+
+  comment:
+    cmd: vhs comment.tape
+
+  iferr:
+    cmd: vhs iferr.tape
+
+  tags:
+    cmd: vhs tags.tape
+
+  impl:
+    cmd: vhs impl.tape

vhs/comment.go

···
+package demos
+
+func doSomethingImportant() {}
+
+type User struct{}
+
+type DataProvider interface{}

vhs/comment.tape

···
+Output comment.gif
+Require nvim
+
+Set FontFamily "JetBrains Mono"
+Set Height 800
+Set Width 1500
+Set Padding 20
+Set Shell "bash"
+Set Theme "tokyonight"
+Set TypingSpeed 250ms
+
+Hide
+Type@0ms "alias nvim='./nvim.sh'" Enter
+Type@0ms "clear" Enter
+Show
+
+Type "nvim comment.go" Sleep 150ms Enter
+
+# package
+Type ":GoCmt" Enter Sleep 500ms Escape Sleep 700ms
+
+# func
+Type "3j"
+Type ":GoCmt" Enter Sleep 500ms Escape Sleep 700ms
+
+# struct
+Type "3j"
+Type ":GoCmt" Enter Sleep 500ms Escape Sleep 700ms
+
+# interface
+Type "3j"
+Type ":GoCmt" Enter Sleep 500ms Escape Sleep 700ms
+
+Sleep 5s

vhs/go.mod

···
+module demos
+
+go 1.25.0

vhs/iferr.go

···
+package demos
+
+func ifErr() {
+	out, err := doSomething()
+
+	_ = out
+}
+
+func doSomething() (string, error) {
+	return "", nil
+}

vhs/iferr.tape

···
+Output iferr.gif
+Require nvim
+Require iferr
+
+Set FontFamily "JetBrains Mono"
+Set Height 800
+Set Width 1500
+Set Padding 20
+Set Shell "bash"
+Set Theme "tokyonight"
+Set TypingSpeed 250ms
+
+Hide
+Type@0ms "alias nvim='./nvim.sh'" Enter
+Type@0ms "clear" Enter
+Show
+
+Type "nvim iferr.go" Sleep 150ms Enter
+
+Type "3j"
+Type ":GoIfErr" Sleep 500ms Enter
+
+Sleep 5s

vhs/impl.go

···
+package demos
+
+type CloserExample struct{}

vhs/impl.tape

···
+Output impl.gif
+Require nvim
+Require iferr
+
+Set FontFamily "JetBrains Mono"
+Set Height 800
+Set Width 1500
+Set Padding 20
+Set Shell "bash"
+Set Theme "tokyonight"
+Set TypingSpeed 250ms
+
+Hide
+Type@0ms "alias nvim='./nvim.sh'" Enter
+Type@0ms "clear" Enter
+Show
+
+Type "nvim impl.go" Sleep 150ms Enter
+
+Type "2j"
+Type ":GoImpl io.Reader" Sleep 500ms Enter
+
+Sleep 5s

vhs/nvim.sh

···
+#!/usr/bin/env bash
+nvim --clean -u "../scripts/minimal_init.lua" $@

vhs/tags.go

···
+package demos
+
+type AddTagsToMe struct {
+	Name    string
+	ID      int
+	Address string
+	Aliases []string
+	Nested  struct {
+		Foo string
+		Bar float32
+	}
+}

vhs/tags.tape

···
+Output tags.gif
+Require nvim
+Require gomodifytags
+
+Set FontFamily "JetBrains Mono"
+Set Height 800
+Set Width 1500
+Set Padding 20
+Set Shell "bash"
+Set Theme "tokyonight"
+Set TypingSpeed 250ms
+
+Hide
+Type@0ms "alias nvim='./nvim.sh'" Enter
+Type@0ms "clear" Enter
+Show
+
+Type "nvim tags.go" Sleep 150ms Enter
+
+Type "3j"
+Type ":GoTagAdd json yaml" Sleep 500ms Enter
+Type@120ms ":w" Enter
+Sleep 1s
+
+Type ":GoTagRm json" Sleep 500ms Enter
+Type@120ms ":w" Enter
+Sleep 1s
+
+Type ":GoTagClear" Sleep 500ms Enter
+Type@120ms ":w" Enter
+Sleep 1s
+
+Type "jV2j"
+Type ":GoTagAdd xml" Sleep 500ms Enter
+
+Sleep 5s