Use nu-highlight for code blocks

.github/workflows/ci.yml

@@ -7,6 +7,9 @@ jobs:
     steps:
       - uses: actions/[email protected]
 
+      - name: Install Nushell
+        run: cargo install nu --locked --no-default-features
+
       - name: Setup Node
         uses: actions/[email protected]
         with:

.vuepress/config.js

@@ -1,4 +1,5 @@
 import path from 'node:path';
+import { execFileSync } from 'node:child_process';
 import { defineUserConfig } from '@vuepress/cli';
 import { gitPlugin } from '@vuepress/plugin-git';
 import { feedPlugin } from '@vuepress/plugin-feed';
@@ -10,6 +11,7 @@ import { copyCodePlugin } from '@vuepress/plugin-copy-code';
 import { docsearchPlugin } from '@vuepress/plugin-docsearch';
 import { backToTopPlugin } from '@vuepress/plugin-back-to-top';
 import { mediumZoomPlugin } from '@vuepress/plugin-medium-zoom';
+import { transformerRenderWhitespace } from '@shikijs/transformers';
 
 import {
   navbarDe,
@@ -192,8 +194,54 @@ export default defineUserConfig({
       },
     }),
     shikiPlugin({
-      theme: 'dark-plus',
+      themes: {
+        dark: 'dark-plus',
+        onedarkpro: 'one-dark-pro', // pre-load one-dark-pro for ansi code blocks
+      },
       lineNumbers: 10,
+      transformers: [
+        transformerRenderWhitespace(),
+        {
+          // highlight nushell code blocks with nu-highlight
+          preprocess(code, options) {
+            if (this.options.lang != 'nushell' && this.options.lang != 'nu') {
+              return code;
+            }
+
+            this.options.defaultColor = 'onedarkpro';
+            // this doesn't work at the top-level for some reason
+            this.options.colorReplacements = {
+              // make one-dark-pro background color the same as dark-plus
+              '#282c34': '#1e1e1e',
+              // HACK: change color of comments, since nu-highlight can't highlight them
+              '#abb2bf': '#80858f',
+            };
+
+            // switch language to ansi, and highlight code blocks with nu-highlight
+            this.options.lang = 'ansi';
+            let result = execFileSync('nu', ['--stdin', 'tools/highlight.nu'], {
+              input: code,
+            });
+            return result.toString().trimEnd();
+          },
+        },
+        // use one-dark-pro theme for ansi code blocks
+        {
+          preprocess(code, options) {
+            if (options.lang == 'ansi') {
+              this.options.defaultColor = 'onedarkpro';
+              // this doesn't work at the top-level for some reason
+              this.options.colorReplacements = {
+                // make one-dark-pro background color the same as dark-plus
+                '#282c34': '#1e1e1e',
+                // HACK: change color of comments, since nu-highlight can't highlight them
+                '#abb2bf': '#80858f',
+              };
+            }
+            return code;
+          },
+        },
+      ],
       langs: [
         'csv',
         'nushell',

book/custom_commands.md

@@ -287,6 +287,10 @@ def "str mycommand" [] {
 Now we can call our custom command as if it were a built-in subcommand of [`str`](/commands/docs/str.md):
 
 ```nu
+def "str mycommand" [] {
+  "hello"
+}
+# BEGIN EXAMPLE
 str mycommand
 ```
 
@@ -444,12 +448,16 @@ greet World
 
 If we try to run the above, Nushell will tell us that the types don't match:
 
-```nu
-error: Type Error
-  ┌─ shell:6:7
-  │
-5 │ greet world
-  │       ^^^^^ Expected int
+```ansi
+Error: nu::parser::parse_mismatch
+
+  × Parse mismatch during operation.
+   ╭─[entry #1:5:7]
+ 4 │
+ 5 │ greet World
+   ·       ──┬──
+   ·         ╰── expected int
+   ╰────
 ```
 
 ::: tip Cool!

book/operators.md

@@ -167,6 +167,9 @@ let cats = ["Mr. Humphrey Montgomery", Kitten]
 
 The below code is an equivalent version using `append`:
 ```nushell
+let dogs = [Spot, Teddy, Tommy]
+let cats = ["Mr. Humphrey Montgomery", Kitten]
+# BEGIN EXAMPLE
 $dogs |
   append Polly |
   append ($cats | each { |elt| $"($elt) \(cat\)" }) |
@@ -209,6 +212,8 @@ You can make a new record with all the fields of `$config` and some new addition
 operator. You can use the spread multiple records inside a single record literal.
 
 ```nushell
+let config = { path: /tmp, limit: 5 }
+# BEGIN EXAMPLE
 {
   ...$config,
   users: [alice bob],

tools/highlight.nu

@@ -0,0 +1,19 @@
+const DELIMITER = "BEGIN EXAMPLE"
+
+def main [] {
+  let source = (
+    $in
+    # prune leading caret
+    | str replace -r '^[>>]\s+' ''
+  )
+  let highlighted = $source | nu-highlight
+  if $DELIMITER in $source {
+    $highlighted
+    | lines
+    | skip while {|line| "BEGIN EXAMPLE" not-in $line}
+    | skip 1 # skip example line itself
+    | to text
+  } else {
+    $highlighted
+  }
+}