From 27bcd4cb5a98bce46c9cdd749752703ead021a4b Mon Sep 17 00:00:00 2001
From: TypeScript Bot <typescriptbot@microsoft.com>
Date: Wed, 10 Apr 2024 01:40:12 +0000
Subject: [PATCH] Update LKG

---
 lib/tsc.js        | 10 ++++------
 lib/tsserver.js   | 10 ++++------
 lib/typescript.js | 10 ++++------
 3 files changed, 12 insertions(+), 18 deletions(-)

diff --git a/lib/tsc.js b/lib/tsc.js
index 65842cbb9ff2e..f4e4fed2bc00f 100644
--- a/lib/tsc.js
+++ b/lib/tsc.js
@@ -55344,12 +55344,10 @@ function createTypeChecker(host) {
     const target = type.target ?? type;
     const typeVariable = getHomomorphicTypeVariable(target);
     if (typeVariable && !target.declaration.nameType) {
-      const constraint = getConstraintTypeFromMappedType(type);
-      if (constraint.flags & 4194304 /* Index */) {
-        const baseConstraint = getBaseConstraintOfType(constraint.type);
-        if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
-          return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
-        }
+      const modifiersType = getModifiersTypeFromMappedType(type);
+      const baseConstraint = isGenericMappedType(modifiersType) ? getApparentTypeOfMappedType(modifiersType) : getBaseConstraintOfType(modifiersType);
+      if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
+        return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
       }
     }
     return type;
diff --git a/lib/tsserver.js b/lib/tsserver.js
index d704e03c5e9c1..3f1ce62663e3c 100644
--- a/lib/tsserver.js
+++ b/lib/tsserver.js
@@ -60088,12 +60088,10 @@ function createTypeChecker(host) {
     const target = type.target ?? type;
     const typeVariable = getHomomorphicTypeVariable(target);
     if (typeVariable && !target.declaration.nameType) {
-      const constraint = getConstraintTypeFromMappedType(type);
-      if (constraint.flags & 4194304 /* Index */) {
-        const baseConstraint = getBaseConstraintOfType(constraint.type);
-        if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
-          return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
-        }
+      const modifiersType = getModifiersTypeFromMappedType(type);
+      const baseConstraint = isGenericMappedType(modifiersType) ? getApparentTypeOfMappedType(modifiersType) : getBaseConstraintOfType(modifiersType);
+      if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
+        return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
       }
     }
     return type;
diff --git a/lib/typescript.js b/lib/typescript.js
index 8668f6089c8c7..22053b17844ef 100644
--- a/lib/typescript.js
+++ b/lib/typescript.js
@@ -57843,12 +57843,10 @@ ${lanes.join("\n")}
       const target = type.target ?? type;
       const typeVariable = getHomomorphicTypeVariable(target);
       if (typeVariable && !target.declaration.nameType) {
-        const constraint = getConstraintTypeFromMappedType(type);
-        if (constraint.flags & 4194304 /* Index */) {
-          const baseConstraint = getBaseConstraintOfType(constraint.type);
-          if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
-            return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
-          }
+        const modifiersType = getModifiersTypeFromMappedType(type);
+        const baseConstraint = isGenericMappedType(modifiersType) ? getApparentTypeOfMappedType(modifiersType) : getBaseConstraintOfType(modifiersType);
+        if (baseConstraint && everyType(baseConstraint, (t) => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) {
+          return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper));
         }
       }
       return type;