Merge branch 'main' into mergeDecoratorsAndModifiers

# Conflicts:
#	src/compiler/checker.ts
#	src/compiler/transformers/ts.ts
#	src/compiler/utilities.ts

Author: rbuckton

CONTRIBUTING.md

@@ -97,6 +97,14 @@ TypeScript is currently accepting contributions in the form of bug fixes. A bug
 
 Features (things that add new or improved functionality to TypeScript) may be accepted, but will need to first be approved (labelled ["help wanted"](https://github.com/Microsoft/TypeScript/issues?q=is%3Aopen+is%3Aissue+label%3A%22help+wanted%22) or in the "Backlog" milestone) by a TypeScript project maintainer in the suggestion issue. Features with language design impact, or that are adequately satisfied with external tools, will not be accepted.
 
+## Issue claiming
+
+If you intend to work on an issue, please avoid leaving comments like "I'm going to work on this". There are a few reasons for this. These comments tend to [discourage anyone from working in the area](https://devblogs.microsoft.com/oldnewthing/20091201-00/?p=15843), yet many issues are much more difficult than they first appear, and you might find yourself trying to fix several issues before finding one that can be completed. Many issues have a long trail of people indicating that they're going to try to fix it, but no PR.
+
+Conversely, you do not need to ask anyone's permission before starting work on an issue marked as "help wanted". It's always fine to try! We ask that you choose issues tagged in the "Backlog" milestone as these are issues that we've identified as needing fixes / implementations.
+
+The sheer quantity of open issues, combined with their general difficulty, makes it extremely unlikely that you and another contributor are a) working on the same issue and b) both going to find a solution.
+
 ## Legal
 
 You will need to complete a Contributor License Agreement (CLA). Briefly, this agreement testifies that you are granting us permission to use the submitted change according to the terms of the project's license, and that the work being submitted is under appropriate copyright. Upon submitting a pull request, you will automatically be given instructions on how to sign the CLA.
@@ -114,6 +122,10 @@ Your pull request should:
 * Follow the code conventions described in [Coding guidelines](https://github.com/Microsoft/TypeScript/wiki/Coding-guidelines)
 * To avoid line ending issues, set `autocrlf = input` and `whitespace = cr-at-eol` in your git configuration
 
+## Force-pushing
+
+Avoid force-pushing your changes, especially when updating your PR based on review feedback. Force-pushed changes are not easily viewable on GitHub, and not at all viewable if a force-push also rebases against main. TypeScript PRs are squash merged, so the specific commits on your PR branch do not matter, only the PR title itself. Don't worry about having a perfect commit history; instead focus on making your changes as easy to review and merge as possible.
+
 ## Contributing `lib.d.ts` fixes
 
 There are three relevant locations to be aware of when it comes to TypeScript's library declaration files:

package-lock.json

@@ -2832,12 +2832,14 @@ namespace ts {
         }
 
         function setCommonJsModuleIndicator(node: Node) {
-            if (file.externalModuleIndicator) {
+            if (file.externalModuleIndicator && file.externalModuleIndicator !== true) {
                 return false;
             }
             if (!file.commonJsModuleIndicator) {
                 file.commonJsModuleIndicator = node;
-                bindSourceFileAsExternalModule();
+                if (!file.externalModuleIndicator) {
+                    bindSourceFileAsExternalModule();
+                }
             }
             return true;
         }
@@ -3289,7 +3291,12 @@ namespace ts {
             }
 
             if (!isBindingPattern(node.name)) {
-                if (isInJSFile(node) && isVariableDeclarationInitializedToBareOrAccessedRequire(node) && !getJSDocTypeTag(node) && !(getCombinedModifierFlags(node) & ModifierFlags.Export)) {
+                const possibleVariableDecl = node.kind === SyntaxKind.VariableDeclaration ? node : node.parent.parent;
+                if (isInJSFile(node) &&
+                    isVariableDeclarationInitializedToBareOrAccessedRequire(possibleVariableDecl) &&
+                    !getJSDocTypeTag(node) &&
+                    !(getCombinedModifierFlags(node) & ModifierFlags.Export)
+                ) {
                     declareSymbolAndAddToSymbolTable(node as Declaration, SymbolFlags.Alias, SymbolFlags.AliasExcludes);
                 }
                 else if (isBlockOrCatchScoped(node)) {