Fix automatic declaration file resolution on Windows

Ref: #2416 (more to do here)

Author: Gerrit0

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Bug Fixes
 
+-   Fixed automatic declaration file resolution on Windows, #2416.
 -   Fixed default option values on options declared by plugins in packages mode, #2433.
 -   `gitRevision` will now be replaced in `sourceLinkTemplate`, #2434.
 -   Improved handling of function-modules created with `Object.assign`, #2436.

src/lib/models/reflections/ReflectionSymbolId.ts

@@ -149,9 +149,11 @@ export function addInferredDeclarationMapPaths(
     const declDir = opts.declarationDir || opts.outDir || rootDir;
 
     for (const file of files) {
-        const mapFile = resolve(declDir, relative(rootDir, file)).replace(
-            /\.([cm]?[tj]s)x?$/,
-            ".d.$1",
+        const mapFile = normalizePath(
+            resolve(declDir, relative(rootDir, file)).replace(
+                /\.([cm]?[tj]s)x?$/,
+                ".d.$1",
+            ),
         );
         declarationMapCache.set(mapFile, file);
     }