Add description support for prettier

This commit adds the descripton tag to prettier and helps
with formatting.

Author: EvilGenius13

.changeset/swift-snails-check.md

@@ -0,0 +1,5 @@
+---
+'@shopify/prettier-plugin-liquid': patch
+---
+
+Add prettier support for the `@description` tag

packages/prettier-plugin-liquid/src/printer/print/liquid.ts

@@ -5,6 +5,7 @@ import {
   RawMarkup,
   LiquidDocParamNode,
   LiquidDocExampleNode,
+  LiquidDocDescriptionNode,
 } from '@shopify/liquid-html-parser';
 import { Doc, doc } from 'prettier';
 
@@ -559,6 +560,22 @@ export function printLiquidDocExample(
   return parts;
 }
 
+export function printLiquidDocDescription(
+  path: AstPath<LiquidDocDescriptionNode>,
+  options: LiquidParserOptions,
+  _print: LiquidPrinter,
+  _args: LiquidPrinterArgs,
+): Doc {
+  const node = path.getValue();
+  const parts: Doc[] = ['@description'];
+
+  if (node.content?.value) {
+    parts.push(' ', node.content.value.trim());
+  }
+
+  return parts;
+}
+
 function innerLeadingWhitespace(node: LiquidTag | LiquidBranch) {
   if (!node.firstChild) {
     if (node.isDanglingWhitespaceSensitive && node.hasDanglingWhitespace) {

packages/prettier-plugin-liquid/src/printer/printer-liquid-html.ts

@@ -1,5 +1,6 @@
 import {
   getConditionalComment,
+  LiquidDocDescriptionNode,
   LiquidDocExampleNode,
   LiquidDocParamNode,
   NodeTypes,
@@ -49,6 +50,7 @@ import {
   printLiquidVariableOutput,
   printLiquidDocParam,
   printLiquidDocExample,
+  printLiquidDocDescription,
 } from './print/liquid';
 import { printClosingTagSuffix, printOpeningTagPrefix } from './print/tag';
 import { bodyLines, hasLineBreakInRange, isEmpty, isTextLikeNode, reindent } from './utils';
@@ -566,7 +568,12 @@ function printNode(
     }
 
     case NodeTypes.LiquidDocDescriptionNode: {
-      return '';
+      return printLiquidDocDescription(
+        path as AstPath<LiquidDocDescriptionNode>,
+        options,
+        print,
+        args,
+      );
     }
 
     default: {

packages/prettier-plugin-liquid/src/test/liquid-doc/fixed.liquid

@@ -88,3 +88,21 @@ It should allow multiple example nodes
   @example
   Second Example
 {% enddoc %}
+
+It should move description content inline
+{% doc %}
+  @description This is a description
+{% enddoc %}
+
+It should add a space between a description tag and content
+{% doc %}
+  @description This is a description
+{% enddoc %}
+
+It should handle param, example, and description nodes
+{% doc %}
+  @param {String} paramName - param with description
+  @example
+  This is a valid example
+  @description This is a description
+{% enddoc %}

packages/prettier-plugin-liquid/src/test/liquid-doc/index.liquid

@@ -87,3 +87,23 @@ It should allow multiple example nodes
   @example
   Second Example
 {% enddoc %}
+
+It should move description content inline
+{% doc %}
+  @description
+  This is a description
+{% enddoc %}
+
+It should add a space between a description tag and content
+{% doc %}
+  @descriptionThis is a description
+{% enddoc %}
+
+It should handle param, example, and description nodes
+{% doc %}
+  @param {String} paramName - param with description
+  @example
+  This is a valid example
+  @description This is a description
+{% enddoc %}
+