Add failing test for arXiv issue

tests/tex-outputs.rs

@@ -199,6 +199,13 @@ fn file_encoding() {
         .go()
 }
 
+#[test]
+fn utf8_chars() {
+    TestCase::new("utf8_chars")
+        .expect(Ok(TexOutcome::Warnings))
+        .go();
+}
+
 /// An issue triggered by a bug in how the I/O subsystem reported file offsets
 /// after an ungetc() call.
 #[test]

tests/tex-outputs/utf8_chars.log

@@ -0,0 +1,13 @@
+**
+(utf8_chars.tex
+Missing character: There is no א (U+05D0) in font [lmroman12-regular]!
+Missing character: There is no ֳ (U+05B3) in font [lmroman12-regular]!
+Missing character: There is no ר (U+05E8) in font [lmroman12-regular]!
+Missing character: There is no ָ (U+05B8) in font [lmroman12-regular]!
+Missing character: There is no נ (U+05E0) in font [lmroman12-regular]!
+Missing character: There is no ִ (U+05B4) in font [lmroman12-regular]!
+Missing character: There is no י (U+05D9) in font [lmroman12-regular]!
+Missing character: There is no ם (U+05DD) in font [lmroman12-regular]!
+Missing character: There is no ֳ (U+05B3) in font [lmroman12-regular]!
+ [1] )
+Output written on utf8_chars.xdv (1 page, 728 bytes).

tests/tex-outputs/utf8_chars.tex

@@ -0,0 +1,8 @@
+% Examples of non-ASCII/Latin text
+\font\r="[lmroman12-regular]"
+
+% Missing in font - intentional
+\r Hebrew: אֳרָנִים
+\r Hebrew modifier on Latin: 9ֳ9
+
+\bye