From ea5581b70ae161d384ab4aae7e1d6f0d178d3b76 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 13 Aug 2020 09:49:46 +0200
Subject: [PATCH 1/2] Keep the original class/function names when minifying
 code (issue 12209)

While this will obviously increase the size of the output of `gulp minified`/`gulp minified-es5` *slightly*, the resulting files are still a lot smaller than the non-minified builds.

See https://github.com/terser/terser#minify-options for information about various Terser options.
---
 gulpfile.js | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/gulpfile.js b/gulpfile.js
index e6739ccd9..a953db9fe 100644
--- a/gulpfile.js
+++ b/gulpfile.js
@@ -909,18 +909,30 @@ function parseMinified(dir) {
   console.log("### Minifying js files");
 
   var Terser = require("terser");
-  // V8 chokes on very long sequences. Works around that.
-  var optsForHugeFile = { compress: { sequences: false } };
+  var options = {
+    compress: {
+      // V8 chokes on very long sequences, work around that.
+      sequences: false,
+    },
+    keep_classnames: true,
+    keep_fnames: true,
+  };
 
-  fs.writeFileSync(dir + "/web/pdf.viewer.js", Terser.minify(viewerFiles).code);
-  fs.writeFileSync(dir + "/build/pdf.min.js", Terser.minify(pdfFile).code);
+  fs.writeFileSync(
+    dir + "/web/pdf.viewer.js",
+    Terser.minify(viewerFiles, options).code
+  );
+  fs.writeFileSync(
+    dir + "/build/pdf.min.js",
+    Terser.minify(pdfFile, options).code
+  );
   fs.writeFileSync(
     dir + "/build/pdf.worker.min.js",
-    Terser.minify(pdfWorkerFile, optsForHugeFile).code
+    Terser.minify(pdfWorkerFile, options).code
   );
   fs.writeFileSync(
     dir + "image_decoders/pdf.image_decoders.min.js",
-    Terser.minify(pdfImageDecodersFile).code
+    Terser.minify(pdfImageDecodersFile, options).code
   );
 
   console.log();

From b26d736809a49941fe2a9fc7b691365496f20eeb Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Thu, 13 Aug 2020 13:17:30 +0200
Subject: [PATCH 2/2] Ensure that the "DocException" message handler, in the
 API, will always either error or warn (depending on the build) if a valid
 `Error` isn't found

Having this present would have made debugging issues 11941 and 12209 so much quicker and easier.
---
 src/display/api.js | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/display/api.js b/src/display/api.js
index c94bf977f..ff17ffec8 100644
--- a/src/display/api.js
+++ b/src/display/api.js
@@ -2271,11 +2271,16 @@ class WorkerTransport {
           reason = new UnknownErrorException(ex.message, ex.details);
           break;
       }
-      if (
-        typeof PDFJSDev === "undefined" ||
-        PDFJSDev.test("!PRODUCTION || TESTING")
-      ) {
-        assert(reason instanceof Error, "DocException: expected an Error.");
+      if (!(reason instanceof Error)) {
+        const msg = "DocException - expected a valid Error.";
+        if (
+          typeof PDFJSDev === "undefined" ||
+          PDFJSDev.test("!PRODUCTION || TESTING")
+        ) {
+          unreachable(msg);
+        } else {
+          warn(msg);
+        }
       }
       loadingTask._capability.reject(reason);
     });