Add support for the import map in the type generator

The typescript compiler is now configured to know about the import map
to be able to resolve those imports and find the associated types.
As tsc outputs declaration files using the original module identifiers
and not the resolved ones, tsc-alias is used to post-process the
declaration files by resolving those paths.

gulpfile.mjs

@@ -266,6 +266,9 @@ function createWebpackConfig(
     viewerAlias["web-com"] = "web/chromecom.js";
     viewerAlias["web-print_service"] = "web/pdf_print_service.js";
   } else if (bundleDefines.GENERIC) {
+    // Aliases defined here must also be replicated in the paths section of
+    // the tsconfig.json file for the type generation to work.
+    // In the tsconfig.json files, the .js extension must be omitted.
     libraryAlias["display-fetch_stream"] = "src/display/fetch_stream.js";
     libraryAlias["display-l10n_utils"] = "web/l10n_utils.js";
     libraryAlias["display-network"] = "src/display/network.js";
@@ -1551,7 +1554,12 @@ gulp.task("types", function (done) {
   console.log("### Generating TypeScript definitions using `tsc`");
   exec(
     `"node_modules/.bin/tsc" --outDir ${TYPES_DIR} --project .`,
-    done
+    function() {
+      exec(
+        `"node_modules/.bin/tsc-alias" --outDir ${TYPES_DIR}`,
+        done
+      )
+    }
   );
 });
 

package.json

@@ -50,6 +50,7 @@
     "stylelint-prettier": "^4.0.2",
     "terser": "^5.19.2",
     "through2": "^4.0.2",
+    "tsc-alias": "^1.8.7",
     "ttest": "^4.0.0",
     "typescript": "^5.1.6",
     "typogr": "^0.6.8",

tsconfig.json

@@ -7,7 +7,18 @@
     "emitDeclarationOnly": true,
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
-    "moduleResolution": "node"
+    "moduleResolution": "node",
+    "paths": {
+      "display-fetch_stream": ["./src/display/fetch_stream"],
+      "display-l10n_utils": ["./web/l10n_utils"],
+      "display-network": ["./src/display/network"],
+      "display-node_stream": ["./src/display/node_stream"],
+      "display-node_utils": ["./src/display/node_utils"],
+      "display-svg": ["./src/display/svg"],
+      "web-com": ["./web/genericcom"],
+      "web-print_service": ["./web/pdf_print_service"],
+      "pdfjs-lib": ["./src/pdf"]
+    }
   },
   "files": [
     "src/pdf.js",