From f5238c328e553df2c0af868173dfd3789d77205f Mon Sep 17 00:00:00 2001
From: graphemecluster <graphemecluster@gmail.com>
Date: Wed, 5 Jun 2024 04:47:58 +0800
Subject: [PATCH] Provide Spelling Suggestions for Named Capture Group
 References in Regular Expressions (#58613)

---
 src/compiler/scanner.ts                              |  6 ++++++
 .../regularExpressionGroupNameSuggestions.errors.txt | 12 ++++++++++++
 .../regularExpressionGroupNameSuggestions.js         |  8 ++++++++
 .../regularExpressionGroupNameSuggestions.symbols    |  6 ++++++
 .../regularExpressionGroupNameSuggestions.types      |  9 +++++++++
 .../regularExpressionGroupNameSuggestions.ts         |  1 +
 6 files changed, 42 insertions(+)
 create mode 100644 tests/baselines/reference/regularExpressionGroupNameSuggestions.errors.txt
 create mode 100644 tests/baselines/reference/regularExpressionGroupNameSuggestions.js
 create mode 100644 tests/baselines/reference/regularExpressionGroupNameSuggestions.symbols
 create mode 100644 tests/baselines/reference/regularExpressionGroupNameSuggestions.types
 create mode 100644 tests/cases/compiler/regularExpressionGroupNameSuggestions.ts

diff --git a/src/compiler/scanner.ts b/src/compiler/scanner.ts
index f30287cf0b0..ad5f270bd4d 100644
--- a/src/compiler/scanner.ts
+++ b/src/compiler/scanner.ts
@@ -3568,6 +3568,12 @@ export function createScanner(languageVersion: ScriptTarget, skipTrivia: boolean
         forEach(groupNameReferences, reference => {
             if (!groupSpecifiers?.has(reference.name)) {
                 error(Diagnostics.There_is_no_capturing_group_named_0_in_this_regular_expression, reference.pos, reference.end - reference.pos, reference.name);
+                if (groupSpecifiers) {
+                    const suggestion = getSpellingSuggestion(reference.name, groupSpecifiers, identity);
+                    if (suggestion) {
+                        error(Diagnostics.Did_you_mean_0, reference.pos, reference.end - reference.pos, suggestion);
+                    }
+                }
             }
         });
         forEach(decimalEscapes, escape => {
diff --git a/tests/baselines/reference/regularExpressionGroupNameSuggestions.errors.txt b/tests/baselines/reference/regularExpressionGroupNameSuggestions.errors.txt
new file mode 100644
index 00000000000..b900c35fe69
--- /dev/null
+++ b/tests/baselines/reference/regularExpressionGroupNameSuggestions.errors.txt
@@ -0,0 +1,12 @@
+regularExpressionGroupNameSuggestions.ts(1,18): error TS1503: Named capturing groups are only available when targeting 'ES2018' or later.
+regularExpressionGroupNameSuggestions.ts(1,27): error TS1532: There is no capturing group named 'Foo' in this regular expression.
+
+
+==== regularExpressionGroupNameSuggestions.ts (2 errors) ====
+    const regex = /(?<foo>)\k<Foo>/;
+                     ~~~~~
+!!! error TS1503: Named capturing groups are only available when targeting 'ES2018' or later.
+                              ~~~
+!!! error TS1532: There is no capturing group named 'Foo' in this regular expression.
+!!! related TS1369: Did you mean 'foo'?
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/regularExpressionGroupNameSuggestions.js b/tests/baselines/reference/regularExpressionGroupNameSuggestions.js
new file mode 100644
index 00000000000..806a861a740
--- /dev/null
+++ b/tests/baselines/reference/regularExpressionGroupNameSuggestions.js
@@ -0,0 +1,8 @@
+//// [tests/cases/compiler/regularExpressionGroupNameSuggestions.ts] ////
+
+//// [regularExpressionGroupNameSuggestions.ts]
+const regex = /(?<foo>)\k<Foo>/;
+
+
+//// [regularExpressionGroupNameSuggestions.js]
+var regex = /(?<foo>)\k<Foo>/;
diff --git a/tests/baselines/reference/regularExpressionGroupNameSuggestions.symbols b/tests/baselines/reference/regularExpressionGroupNameSuggestions.symbols
new file mode 100644
index 00000000000..2b4d2d7407e
--- /dev/null
+++ b/tests/baselines/reference/regularExpressionGroupNameSuggestions.symbols
@@ -0,0 +1,6 @@
+//// [tests/cases/compiler/regularExpressionGroupNameSuggestions.ts] ////
+
+=== regularExpressionGroupNameSuggestions.ts ===
+const regex = /(?<foo>)\k<Foo>/;
+>regex : Symbol(regex, Decl(regularExpressionGroupNameSuggestions.ts, 0, 5))
+
diff --git a/tests/baselines/reference/regularExpressionGroupNameSuggestions.types b/tests/baselines/reference/regularExpressionGroupNameSuggestions.types
new file mode 100644
index 00000000000..a9d110f6ddf
--- /dev/null
+++ b/tests/baselines/reference/regularExpressionGroupNameSuggestions.types
@@ -0,0 +1,9 @@
+//// [tests/cases/compiler/regularExpressionGroupNameSuggestions.ts] ////
+
+=== regularExpressionGroupNameSuggestions.ts ===
+const regex = /(?<foo>)\k<Foo>/;
+>regex : RegExp
+>      : ^^^^^^
+>/(?<foo>)\k<Foo>/ : RegExp
+>                  : ^^^^^^
+
diff --git a/tests/cases/compiler/regularExpressionGroupNameSuggestions.ts b/tests/cases/compiler/regularExpressionGroupNameSuggestions.ts
new file mode 100644
index 00000000000..f1960c6cbcb
--- /dev/null
+++ b/tests/cases/compiler/regularExpressionGroupNameSuggestions.ts
@@ -0,0 +1 @@
+const regex = /(?<foo>)\k<Foo>/;