1 files changed, 185 insertions, 0 deletions
diff --git a/tests/test_parse_simple_string.rs b/tests/test_parse_simple_string.rs
new file mode 100644
index 0000000..2e9ed11
--- /dev/null
+++ b/tests/test_parse_simple_string.rs
@@ -0,0 +1,185 @@
+use codecrafters_redis::resp_parser::*;
+
+#[test]
+fn test_valid_simple_strings() {
+    // Basic valid cases
+    assert_eq!(parse_simple_strings(b"+OK\r\n").unwrap().0, "OK");
+    assert_eq!(parse_simple_strings(b"+PONG\r\n").unwrap().0, "PONG");
+    assert_eq!(
+        parse_simple_strings(b"+Hello World\r\n").unwrap().0,
+        "Hello World"
+    );
+
+    // Empty string
+    assert_eq!(parse_simple_strings(b"+\r\n").unwrap().0, "");
+
+    // String with spaces and special characters (but no \r or \n)
+    assert_eq!(
+        parse_simple_strings(b"+Hello, World! 123\r\n").unwrap().0,
+        "Hello, World! 123"
+    );
+
+    // String with various ASCII characters
+    assert_eq!(
+        parse_simple_strings(b"+!@#$%^&*()_+-={}[]|\\:;\"'<>?,./ \r\n")
+            .unwrap()
+            .0,
+        "!@#$%^&*()_+-={}[]|\\:;\"'<>?,./ "
+    );
+
+    // Unicode characters (should work with UTF-8)
+    assert_eq!(
+        parse_simple_strings(b"+\xc3\xa9\xc3\xa1\xc3\xb1\r\n")
+            .unwrap()
+            .0,
+        "éáñ"
+    );
+}
+
+#[test]
+fn test_invalid_prefix() {
+    // Missing '+' prefix
+    assert_eq!(
+        parse_simple_strings(b"OK\r\n").err().unwrap().message(),
+        "WRONGTYPE Operation against a key holding the wrong kind of value"
+    );
+
+    // Wrong prefix
+    assert_eq!(
+        parse_simple_strings(b"-Error\r\n").err().unwrap().message(),
+        "WRONGTYPE Operation against a key holding the wrong kind of value"
+    );
+    assert_eq!(
+        parse_simple_strings(b":123\r\n").err().unwrap().message(),
+        "WRONGTYPE Operation against a key holding the wrong kind of value"
+    );
+    assert_eq!(
+        parse_simple_strings(b"$5\r\nhello\r\n")
+            .err()
+            .unwrap()
+            .message(),
+        "WRONGTYPE Operation against a key holding the wrong kind of value"
+    );
+}
+
+#[test]
+fn test_missing_crlf_terminator() {
+    // No CRLF at all
+    assert_eq!(
+        parse_simple_strings(b"+OK").err().unwrap().message(),
+        "ERR Unexpected end of input"
+    );
+
+    // Only \r
+    assert_eq!(
+        parse_simple_strings(b"+OK\r").err().unwrap().message(),
+        "ERR Unexpected end of input"
+    );
+
+    // Only \n
+    assert_eq!(
+        parse_simple_strings(b"+OK\n").err().unwrap().message(),
+        "ERR Unexpected end of input"
+    );
+
+    // Wrong order (\n\r instead of \r\n)
+    assert_eq!(
+        parse_simple_strings(b"+OK\n\r").err().unwrap().message(),
+        "ERR Unexpected end of input"
+    );
+}
+
+#[test]
+fn test_invalid_characters_in_content() {
+    // Contains \r in content
+    assert_eq!(
+        parse_simple_strings(b"+Hello\rWorld\r\n")
+            .err()
+            .unwrap()
+            .message(),
+        "ERR invalid value"
+    );
+
+    // Contains \n in content
+    assert_eq!(
+        parse_simple_strings(b"+Hello\nWorld\r\n")
+            .err()
+            .unwrap()
+            .message(),
+        "ERR invalid value"
+    );
+}
+
+#[test]
+fn test_empty_input() {
+    assert_eq!(
+        parse_simple_strings(b"").err().unwrap().message(),
+        "ERR Empty data"
+    );
+}
+
+#[test]
+fn test_with_trailing_data() {
+    // RESP simple string with extra data after CRLF (should be ignored)
+    assert_eq!(parse_simple_strings(b"+OK\r\nextra_data").unwrap().0, "OK");
+    assert_eq!(
+        parse_simple_strings(b"+PONG\r\n+another_string\r\n")
+            .unwrap()
+            .0,
+        "PONG"
+    );
+}
+
+#[test]
+fn test_real_world_redis_responses() {
+    // Common Redis simple string responses
+    assert_eq!(parse_simple_strings(b"+OK\r\n").unwrap().0, "OK");
+    assert_eq!(parse_simple_strings(b"+PONG\r\n").unwrap().0, "PONG");
+    assert_eq!(parse_simple_strings(b"+QUEUED\r\n").unwrap().0, "QUEUED");
+
+    // Redis status responses
+    assert_eq!(
+        parse_simple_strings(b"+Background saving started\r\n")
+            .unwrap()
+            .0,
+        "Background saving started"
+    );
+    assert_eq!(
+        parse_simple_strings(b"+Background saving successfully finished\r\n")
+            .unwrap()
+            .0,
+        "Background saving successfully finished"
+    );
+}
+
+#[test]
+fn test_edge_cases() {
+    // Just the prefix and CRLF
+    assert_eq!(parse_simple_strings(b"+\r\n").unwrap().0, "");
+
+    // Long string
+    let long_string = "a".repeat(1000);
+    let mut input = b"+".to_vec();
+    input.extend_from_slice(long_string.as_bytes());
+    input.extend_from_slice(b"\r\n");
+    assert_eq!(parse_simple_strings(&input).unwrap().0, long_string);
+
+    // String with only spaces
+    assert_eq!(parse_simple_strings(b"+   \r\n").unwrap().0, "   ");
+
+    // String with tabs and other whitespace
+    assert_eq!(parse_simple_strings(b"+\t  \t\r\n").unwrap().0, "\t  \t");
+}
+
+#[test]
+fn test_binary_safety_within_limits() {
+    // Non-UTF8 bytes (but no \r or \n)
+    let mut input = b"+".to_vec();
+    input.extend_from_slice(&[0xFF, 0xFE, 0xFD]); // Invalid UTF-8
+    input.extend_from_slice(b"\r\n");
+
+    // Should handle invalid UTF-8 gracefully with replacement characters
+    if let RespType::SimpleString(data) = parse_simple_strings(&input).unwrap().0 {
+        assert!(!data.is_empty()); // Should contain replacement characters
+    }
+}