docs/manual: document building plugins from source

docs/manual/tips.md

@@ -1,7 +1,8 @@
 # Helpful Tips {#ch-helpful-tips}
 
 ```{=include=} chapters
-tips/pure-lua-config.md
 tips/debugging-nvf.md
 tips/offline-docs.md
+tips/pure-lua-config.md
+tips/plugin-sources.md
 ```

docs/manual/tips/plugin-sources.md

@@ -0,0 +1,131 @@
+# Adding Plugins From Different Sources {#sec-plugin-sources}
+
+**nvf** attempts to avoid depending on Nixpkgs for Neovim plugins. For the most
+part, this is accomplished by defining each plugin's source and building them
+from source.
+
+[npins]: https://github.com/andir/npins
+
+To define plugin sources, we use [npins] and pin each plugin source using
+builtin fetchers. You are not bound by this restriction. In your own
+configuration, any kind of fetcher or plugin source is fine.
+
+## Nixpkgs & Friends {#ch-plugins-from-nixpkgs}
+
+`vim.startPlugins` and `vim.optPlugins` options take either a **string**, in
+which case a plugin from nvf's internal plugins registry will be used, or a
+**package**. If your plugin does not require any setup, or ordering for it s
+configuration, then it is possible to add it to `vim.startPlugins` to load it on
+startup.
+
+```nix
+{pkgs, ...}: {
+  # Aerial does require some setup. In the case you pass a plugin that *does*
+  # require manual setup, then you must also call the setup function.
+  vim.startPlugins = [pkgs.vimPlugins.aerial-nvim];
+}
+```
+
+[`vim.extraPlugins`]: https://notashelf.github.io/nvf/options.html#opt-vim.extraPlugins
+
+This will fetch aerial.nvim from nixpkgs, and add it to Neovim's runtime path to
+be loaded manually. Although for plugins that require manual setup, you are
+encouraged to use [`vim.extraPlugins`].
+
+```nix
+{
+  vim.extraPlugins = {
+    aerial = {
+      package = pkgs.vimPlugins.aerial-nvim;
+      setup = "require('aerial').setup {}";
+    };
+  };
+}
+```
+
+[custom plugins section]: https://notashelf.github.io/nvf/index.xhtml#ch-custom-plugins
+
+More details on the extraPlugins API is documented in the
+[custom plugins section].
+
+## Building Your Own Plugins {#ch-plugins-from-source}
+
+In the case a plugin is not available in Nixpkgs, or the Nixpkgs package is
+outdated (or, more likely, broken) it is possible to build the plugins from
+source using a tool, such as [npins]. You may also use your _flake inputs_ as
+sources.
+
+Example using plugin inputs:
+
+```nix
+{
+  # In your flake.nix
+  inputs = {
+    aerial-nvim = {
+      url = "github:stevearc/aerial.nvim"
+      flake = false;
+    };
+  };
+
+  # Make sure that 'inputs' is properly propagated into Nvf, for example, through
+  # specialArgs.
+  outputs = { ... };
+}
+```
+
+In the case, you may use the input directly for the plugin's source attribute in
+`buildVimPlugin`.
+
+```nix
+# Make sure that 'inputs' is properly propagated! It will be missing otherwise
+# and the resulting errors might be too obscure.
+{inputs, ...}: let
+  aerial-from-source = pkgs.vimUtils.buildVimPlugin {
+      name = "aerial-nvim";
+      src = inputs.aerial-nvim;
+    };
+in {
+  vim.extraPlugins = {
+    aerial = {
+      package = aerial-from-source;
+      setup = "require('aerial').setup {}";
+    };
+  };
+}
+```
+
+Alternatively, if you do not want to keep track of the source using flake inputs
+or npins, you may call `fetchFromGitHub` (or other fetchers) directly. An
+example would look like this.
+
+```nix
+regexplainer = buildVimPlugin {
+  name = "nvim-regexplainer";
+  src = fetchFromGitHub {
+    owner = "bennypowers";
+    repo = "nvim-regexplainer";
+    rev = "4250c8f3c1307876384e70eeedde5149249e154f";
+    hash = "sha256-15DLbKtOgUPq4DcF71jFYu31faDn52k3P1x47GL3+b0=";
+  };
+
+  # The 'buildVimPlugin' imposes some "require checks" on all plugins build from
+  # source. Failing tests, if they are not relevant, can be disabled using the
+  # 'nvimSkipModule' argument to the 'buildVimPlugin' function.
+  nvimSkipModule = [
+    "regexplainer"
+    "regexplainer.buffers.init"
+    "regexplainer.buffers.popup"
+    "regexplainer.buffers.register"
+    "regexplainer.buffers.shared"
+    "regexplainer.buffers.split"
+    "regexplainer.component.descriptions"
+    "regexplainer.component.init"
+    "regexplainer.renderers.narrative.init"
+    "regexplainer.renderers.narrative.narrative"
+    "regexplainer.renderers.init"
+    "regexplainer.utils.defer"
+    "regexplainer.utils.init"
+    "regexplainer.utils.treesitter"
+  ];
+}
+```