hashsum: handle the case when md5sum is used but the file contains a different algo

src/uucore/src/lib/features/checksum.rs

@@ -378,6 +378,16 @@ where
                 let (algo_name, length) = if algo_based_format {
                     // When the algo-based format is matched, extract details from regex captures
                     let algorithm = caps.name("algo").map_or("", |m| m.as_str()).to_lowercase();
+
+                    // check if we are called with XXXsum (example: md5sum) but we detected a different algo parsing the file
+                    // (for example SHA1 (f) = d...)
+                    // Also handle the case cksum -s sm3 but the file contains other formats
+                    if algo_name_input.is_some() && algo_name_input != Some(&algorithm) {
+                        bad_format += 1;
+                        properly_formatted = false;
+                        continue;
+                    }
+
                     if !SUPPORTED_ALGO.contains(&algorithm.as_str()) {
                         // Not supported algo, leave early
                         properly_formatted = false;
@@ -507,6 +517,7 @@ where
                 .maybe_quote()
             );
             set_exit_code(1);
+            return Ok(());
         }
 
         if ignore_missing && correct_format == 0 {

tests/by-util/test_cksum.rs

@@ -1057,15 +1057,21 @@ fn test_cksum_mixed() {
         let result = scene.ucmd().args(command).arg("f").succeeds();
         at.append("CHECKSUM", result.stdout_str());
     }
-    scene
+    println!("Content of CHECKSUM:\n{}", at.read("CHECKSUM"));
+    let result = scene
         .ucmd()
         .arg("--check")
         .arg("-a")
         .arg("sm3")
         .arg("CHECKSUM")
-        .succeeds()
-        .stdout_contains("f: OK")
-        .stderr_contains("3 lines are improperly formatted");
+        .succeeds();
+
+    println!("result.stderr_str() {}", result.stderr_str());
+    println!("result.stdout_str() {}", result.stdout_str());
+    assert!(result.stdout_str().contains("f: OK"));
+    assert!(result
+        .stderr_str()
+        .contains("3 lines are improperly formatted"));
 }
 
 #[test]

tests/by-util/test_hashsum.rs

@@ -668,6 +668,22 @@ fn test_check_status_code() {
         .stdout_is("");
 }
 
+#[test]
+fn test_sha1_with_md5sum_should_fail() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+
+    at.touch("f");
+    at.write("f.sha1", "SHA1 (f) = d41d8cd98f00b204e9800998ecf8427e\n");
+    scene
+        .ccmd("md5sum")
+        .arg("--check")
+        .arg(at.subdir.join("f.sha1"))
+        .fails()
+        .stderr_contains("f.sha1: no properly formatted checksum lines found")
+        .stderr_does_not_contain("WARNING: 1 line is improperly formatted");
+}
+
 #[test]
 fn test_check_no_backslash_no_space() {
     let scene = TestScenario::new(util_name!());