feat: support cbr reading

tests/cbr_reader_tests.rs

@@ -0,0 +1,23 @@
+use std::fs::File;
+use std::io::Write;
+
+use cbz2pdf::formats::cbr::CbrReader;
+use cbz2pdf::formats::FormatReader;
+
+// We cannot reliably create a RAR archive in tests (tools cannot create .rar),
+// Instead, verify that the reader fails gracefully (returns an error) when given an invalid .cbr
+// file.
+#[test]
+fn cbr_reader_errors_on_invalid_archive() {
+    let temp_dir = tempfile::tempdir().expect("create temp dir");
+    let cbr_path = temp_dir.path().join("invalid.cbr");
+
+    // Write some junk that is definitely not a RAR archive
+    let mut f = File::create(&cbr_path).expect("create cbr");
+    f.write_all(b"this is not a rar archive").unwrap();
+
+    let reader = CbrReader;
+    let res = reader.read(&cbr_path);
+
+    assert!(res.is_err(), "CbrReader should error on invalid archives");
+}

tests/job_and_format_tests.rs

@@ -7,8 +7,10 @@ use cbz2pdf::job::Job;
 fn detect_from_path_recognizes_extensions() {
     let cbz = PathBuf::from("/tmp/book.cbz");
     let pdf = PathBuf::from("/tmp/book.pdf");
+    let cbr = PathBuf::from("/tmp/book.cbr");
     assert_eq!(FormatId::detect_from_path(&cbz), Some(FormatId::Cbz));
     assert_eq!(FormatId::detect_from_path(&pdf), Some(FormatId::Pdf));
+    assert_eq!(FormatId::detect_from_path(&cbr), Some(FormatId::Cbr));
     assert_eq!(
         FormatId::detect_from_path(&PathBuf::from("/tmp/book.txt")),
         None
@@ -24,11 +26,19 @@ fn job_new_sets_output_extension() {
 
     let job2 = Job::new(
         PathBuf::from("/tmp/book.pdf"),
-        outdir,
+        outdir.clone(),
         FormatId::Pdf,
         FormatId::Cbz,
     );
     assert!(job2.output_path.ends_with("book.cbz"));
+
+    let job3 = Job::new(
+        PathBuf::from("/tmp/book.cbz"),
+        outdir,
+        FormatId::Cbz,
+        FormatId::Cbr,
+    );
+    assert!(job3.output_path.ends_with("book.cbr"));
 }
 
 #[test]
@@ -37,4 +47,6 @@ fn format_capabilities_consistent() {
     assert!(FormatId::Cbz.can_write());
     assert!(FormatId::Pdf.can_write());
     assert!(FormatId::Pdf.can_read());
+    assert!(FormatId::Cbr.can_read());
+    assert!(!FormatId::Cbr.can_write());
 }