Improve keyword detection in TSModuleDeclaration

src/language-js/print/module.js

@@ -1,5 +1,3 @@
-import assert from "node:assert";
-
 import {
   group,
   hardline,
@@ -13,6 +11,7 @@ import { printDanglingComments } from "../../main/comments/print.js";
 import isNonEmptyArray from "../../utils/is-non-empty-array.js";
 import UnexpectedNodeError from "../../utils/unexpected-node-error.js";
 import { hasSameLoc, locEnd, locStart } from "../loc.js";
+import getTextWithoutComments from "../utils/get-text-without-comments.js";
 import {
   CommentCheckFlags,
   createTypeCheckFunction,
@@ -249,35 +248,6 @@ function shouldPrintSpecifiers(node, options) {
   return text.trimEnd().endsWith("from");
 }
 
-function getTextWithoutComments(options, start, end) {
-  let text = options.originalText.slice(start, end);
-
-  for (const comment of options[Symbol.for("comments")]) {
-    const commentStart = locStart(comment);
-    // Comments are sorted, we can escape if the comment is after the range
-    if (commentStart > end) {
-      break;
-    }
-
-    const commentEnd = locEnd(comment);
-    if (commentEnd < start) {
-      continue;
-    }
-
-    const commentLength = commentEnd - commentStart;
-    text =
-      text.slice(0, commentStart - start) +
-      " ".repeat(commentLength) +
-      text.slice(commentEnd - start);
-  }
-
-  if (process.env.NODE_ENV !== "production") {
-    assert(text.length === end - start);
-  }
-
-  return text;
-}
-
 function getImportAttributesKeyword(node, options) {
   // Babel parser add this property to indicate the keyword is `assert`
   if (node.extra?.deprecatedAssertSyntax) {

src/language-js/print/typescript.js

@@ -8,6 +8,7 @@ import {
 } from "../../document/builders.js";
 import UnexpectedNodeError from "../../utils/unexpected-node-error.js";
 import { locStart } from "../loc.js";
+import getTextWithoutComments from "../utils/get-text-without-comments.js";
 import {
   isArrayOrTupleExpression,
   isObjectOrRecordExpression,
@@ -311,9 +312,9 @@ function printTypescript(path, options, print) {
             node.kind ??
             // TODO: Use `node.kind` when babel update AST
             (isStringLiteral(node.id) ||
-            /(?:^|\s)module(?:\s|$)/.test(
-              options.originalText.slice(locStart(node), locStart(node.id)),
-            )
+            getTextWithoutComments(options, locStart(node), locStart(node.id))
+              .trim()
+              .endsWith("module")
               ? "module"
               : "namespace");
           parts.push(kind, " ");

src/language-js/utils/get-text-without-comments.js

@@ -0,0 +1,34 @@
+import assert from "node:assert";
+
+import { locEnd, locStart } from "../loc.js";
+
+function getTextWithoutComments(options, start, end) {
+  let text = options.originalText.slice(start, end);
+
+  for (const comment of options[Symbol.for("comments")]) {
+    const commentStart = locStart(comment);
+    // Comments are sorted, we can escape if the comment is after the range
+    if (commentStart > end) {
+      break;
+    }
+
+    const commentEnd = locEnd(comment);
+    if (commentEnd < start) {
+      continue;
+    }
+
+    const commentLength = commentEnd - commentStart;
+    text =
+      text.slice(0, commentStart - start) +
+      " ".repeat(commentLength) +
+      text.slice(commentEnd - start);
+  }
+
+  if (process.env.NODE_ENV !== "production") {
+    assert(text.length === end - start);
+  }
+
+  return text;
+}
+
+export default getTextWithoutComments;

tests/format/typescript/module/__snapshots__/jsfmt.spec.js.snap

@@ -80,6 +80,10 @@ namespace X {
   }
 }
 
+namespace /* module */ X {}
+module /* namespace */ X {}
+module /* namespace */ "x" {}
+
 =====================================output=====================================
 module X {}
 
@@ -113,6 +117,10 @@ namespace X {
   }
 }
 
+namespace /* module */ X {}
+module /* namespace */ X {}
+module /* namespace */ "x" {}
+
 ================================================================================
 `;
 

tests/format/typescript/module/keyword.ts

@@ -29,3 +29,7 @@ namespace X {
     const x = 1;
   }
 }
+
+namespace /* module */ X {}
+module /* namespace */ X {}
+module /* namespace */ "x" {}