From 4bf4b86e92d6d37f4a23811420d7d22d14691936 Mon Sep 17 00:00:00 2001
From: John Simons <john.simons@particular.net>
Date: Tue, 15 Oct 2024 16:42:49 +1000
Subject: [PATCH] endregion snippet extraction does not require tag

The snippet extraction via region syntax from VSCode does not require the endregion to have a matching tag
---
 .../node/markdown/plugins/snippet.test.ts     | 143 +++++++++++++++++-
 src/node/markdown/plugins/snippet.ts          |  49 +++---
 2 files changed, 172 insertions(+), 20 deletions(-)

diff --git a/__tests__/unit/node/markdown/plugins/snippet.test.ts b/__tests__/unit/node/markdown/plugins/snippet.test.ts
index 0ae97dd2afcd..0781b3738a60 100644
--- a/__tests__/unit/node/markdown/plugins/snippet.test.ts
+++ b/__tests__/unit/node/markdown/plugins/snippet.test.ts
@@ -1,4 +1,9 @@
-import { dedent, rawPathToToken } from 'node/markdown/plugins/snippet'
+import {
+  dedent,
+  findRegion,
+  rawPathToToken
+} from 'node/markdown/plugins/snippet'
+import { expect } from 'vitest'
 
 const removeEmptyKeys = <T extends Record<string, unknown>>(obj: T) => {
   return Object.fromEntries(
@@ -99,4 +104,140 @@ describe('node/markdown/plugins/snippet', () => {
       expect(removeEmptyKeys(rawPathToToken(rawPath))).toEqual(token)
     })
   })
+
+  describe('findRegion', () => {
+    test('when c# region with matching tag', () => {
+      const lines = `Console.WriteLine("Before region");
+#region hello
+Console.WriteLine("Hello, World!");
+#endregion hello
+Console.WriteLine("After region");`.split('\n')
+      const result = findRegion(lines, 'hello')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        'Console.WriteLine("Hello, World!");'
+      )
+    })
+    test('when c# region is not indented with spaces and no matching tag', () => {
+      const lines = `Console.WriteLine("Before region");
+#region hello
+Console.WriteLine("Hello, World!");
+#endregion
+Console.WriteLine("After region");`.split('\n')
+      const result = findRegion(lines, 'hello')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        'Console.WriteLine("Hello, World!");'
+      )
+    })
+    test('when c# region is indented with spaces and no matching tag', () => {
+      const lines = `  Console.WriteLine("Before region");
+  #region hello
+  Console.WriteLine("Hello, World!");
+  #endregion hello
+  Console.WriteLine("After region");`.split('\n')
+      const result = findRegion(lines, 'hello')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  Console.WriteLine("Hello, World!");'
+      )
+    })
+    test('when c# region with matching tag', () => {
+      const lines = `Console.WriteLine("Before region");
+#region hello
+Console.WriteLine("Hello, World!");
+#endregion hello
+Console.WriteLine("After region");`.split('\n')
+      const result = findRegion(lines, 'hello')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        'Console.WriteLine("Hello, World!");'
+      )
+    })
+    test('when c# region is not indented with spaces and no matching tag', () => {
+      const lines = `Console.WriteLine("Before region");
+#region hello
+Console.WriteLine("Hello, World!");
+#endregion
+Console.WriteLine("After region");`.split('\n')
+      const result = findRegion(lines, 'hello')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        'Console.WriteLine("Hello, World!");'
+      )
+    })
+
+    test('when typescript region has matching tag', () => {
+      const lines = `let regexp: RegExp[] = []
+// #region foo
+let start = -1
+// #endregion foo`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        'let start = -1'
+      )
+    })
+    test('when typescript region is indented with spaces and no matching tag', () => {
+      const lines = `  let regexp: RegExp[] = []
+  // #region foo
+  let start = -1
+  // #endregion`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  let start = -1'
+      )
+    })
+
+    test('when css region has matching tag', () => {
+      const lines = `.body-content {
+/* #region foo */
+  padding-left: 15px;
+/* #endregion foo */
+  padding-right: 15px;
+}`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  padding-left: 15px;'
+      )
+    })
+    test('when css region is indented with spaces and no matching tag', () => {
+      const lines = `.body-content {
+  /* #region foo */
+  padding-left: 15px;
+  /* #endregion */
+  padding-right: 15px;
+}`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  padding-left: 15px;'
+      )
+    })
+
+    test('when html region has matching tag', () => {
+      const lines = `<!-- #region foo -->
+  <h1>Hello world</h1>
+<!-- #endregion foo -->
+  <p>more text</p>`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  <h1>Hello world</h1>'
+      )
+    })
+    test('when html region is indented with spaces and no matching tag', () => {
+      const lines = `  <!-- #region foo -->
+  <h1>Hello world</h1>
+  <!-- #endregion foo -->
+  <p>more text</p>`.split('\n')
+      const result = findRegion(lines, 'foo')
+
+      expect(lines.slice(result?.start, result?.end).join('\n')).toBe(
+        '  <h1>Hello world</h1>'
+      )
+    })
+  })
 })
diff --git a/src/node/markdown/plugins/snippet.ts b/src/node/markdown/plugins/snippet.ts
index 17131de2472e..8b8251661640 100644
--- a/src/node/markdown/plugins/snippet.ts
+++ b/src/node/markdown/plugins/snippet.ts
@@ -59,38 +59,43 @@ function testLine(
 ) {
   const [full, tag, name] = regexp.exec(line.trim()) || []
 
-  return (
-    full &&
-    tag &&
-    name === regionName &&
-    tag.match(end ? /^[Ee]nd ?[rR]egion$/ : /^[rR]egion$/)
-  )
+  return full && tag && end
+    ? true
+    : name === regionName &&
+        tag.match(end ? /^[Ee]nd ?[rR]egion$/ : /^[rR]egion$/)
 }
 
 export function findRegion(lines: Array<string>, regionName: string) {
   const regionRegexps = [
-    /^\/\/ ?#?((?:end)?region) ([\w*-]+)$/, // javascript, typescript, java
-    /^\/\* ?#((?:end)?region) ([\w*-]+) ?\*\/$/, // css, less, scss
-    /^#pragma ((?:end)?region) ([\w*-]+)$/, // C, C++
-    /^<!-- #?((?:end)?region) ([\w*-]+) -->$/, // HTML, markdown
-    /^#((?:End )Region) ([\w*-]+)$/, // Visual Basic
-    /^::#((?:end)region) ([\w*-]+)$/, // Bat
-    /^# ?((?:end)?region) ([\w*-]+)$/ // C#, PHP, Powershell, Python, perl & misc
+    [
+      /^[ \t]*\/\/ ?#?(region) ([\w*-]+)$/,
+      /^[ \t]*\/\/ ?#?(endregion) ?([\w*-]*)$/
+    ], // javascript, typescript, java
+    [
+      /^\/\* ?#(region) ([\w*-]+) ?\*\/$/,
+      /^\/\* ?#(endregion) ?([\w*-]*) ?\*\/$/
+    ], // css, less, scss
+    [/^#pragma (region) ([\w*-]+)$/, /^#pragma (endregion) ?([\w*-]*)$/], // C, C++
+    [/^<!-- #?(region) ([\w*-]+) -->$/, /^<!-- #?(endregion) ?([\w*-]*) -->$/], // HTML, markdown
+    [/^[ \t]*#(Region) ([\w*-]+)$/, /^[ \t]*#(End Region) ?([\w*-]*)$/], // Visual Basic
+    [/^::#(region) ([\w*-]+)$/, /^::#(endregion) ?([\w*-]*)$/], // Bat
+    [/^[ \t]*# ?(region) ([\w*-]+)$/, /^[ \t]*# ?(endregion) ?([\w*-]*)$/] // C#, PHP, Powershell, Python, perl & misc
   ]
 
-  let regexp = null
+  // #reqion foo
+  let regexp: RegExp[] = []
   let start = -1
-
+  // #endregion
   for (const [lineId, line] of lines.entries()) {
-    if (regexp === null) {
+    if (regexp.length === 0) {
       for (const reg of regionRegexps) {
-        if (testLine(line, reg, regionName)) {
+        if (testLine(line, reg[0], regionName)) {
           start = lineId + 1
           regexp = reg
           break
         }
       }
-    } else if (testLine(line, regexp, regionName, true)) {
+    } else if (testLine(line, regexp[1], regionName, true)) {
       return { start, end: lineId, regexp }
     }
   }
@@ -181,7 +186,13 @@ export const snippetPlugin = (md: MarkdownIt, srcDir: string) => {
         content = dedent(
           lines
             .slice(region.start, region.end)
-            .filter((line) => !region.regexp.test(line.trim()))
+            .filter((line) => {
+              const trimmed = line.trim()
+              return (
+                !region.regexp[0].test(trimmed) &&
+                !region.regexp[1].test(trimmed)
+              )
+            })
             .join('\n')
         )
       }