feat(nuldoc): improve readability of error messages

1 files changed, 11 insertions, 1 deletions

diff --git a/nuldoc-src/xml.ts b/nuldoc-src/xml.ts
index 87c2b71..847b5e1 100644
--- a/nuldoc-src/xml.ts
+++ b/nuldoc-src/xml.ts
@@ -203,7 +203,9 @@ function expect(p: Parser, expected: string) {
   }
   if (actual !== expected) {
     throw new XmlParseError(
-      `[parse.expect] expected ${expected}, but actually got ${actual} (pos: ${p.index})`,
+      `[parse.expect] expected ${expected}, but actually got ${
+        escapeForHuman(actual)
+      } (pos: ${p.index})`,
     );
   }
 }
@@ -257,3 +259,11 @@ function replaceEntityReferences(s: string): string {
     .replaceAll(/'/g, "'")
     .replaceAll(/"/g, '"');
 }
+
+function escapeForHuman(s: string): string {
+  // support more characters?
+  return s
+    .replaceAll("\n", "\\n")
+    .replaceAll("\t", "\\t")
+    .replaceAll("\r", "\\r");
+}