1 files changed, 58 insertions, 0 deletions
diff --git a/src/gen/rust/quote.rs b/src/gen/rust/quote.rs
new file mode 100644
index 0000000..f01b4ee
--- /dev/null
+++ b/src/gen/rust/quote.rs
@@ -0,0 +1,58 @@
+fn hex_digit(value: u32) -> char {
+    if value < 10 {
+        (b'0' + value as u8) as char
+    } else if value < 0x10 {
+        (b'a' + value as u8 - 10) as char
+    } else {
+        unreachable!()
+    }
+}
+
+pub fn quote_escape_str(s: &str) -> String {
+    let mut buf = String::new();
+    buf.push('"');
+    buf.extend(s.chars().flat_map(|c| c.escape_default()));
+    buf.push('"');
+    buf
+}
+
+pub fn quote_escape_bytes(bytes: &[u8]) -> String {
+    let mut buf = String::new();
+    buf.push('b');
+    buf.push('"');
+    for &b in bytes {
+        match b {
+            b'\n' => buf.push_str(r"\n"),
+            b'\r' => buf.push_str(r"\r"),
+            b'\t' => buf.push_str(r"\t"),
+            b'"' => buf.push_str("\\\""),
+            b'\\' => buf.push_str(r"\\"),
+            b'\x20'..=b'\x7e' => buf.push(b as char),
+            _ => {
+                buf.push_str(r"\x");
+                buf.push(hex_digit((b as u32) >> 4));
+                buf.push(hex_digit((b as u32) & 0x0f));
+            }
+        }
+    }
+    buf.push('"');
+    buf
+}
+
+#[cfg(test)]
+mod test {
+
+    use super::*;
+
+    #[test]
+    fn test_quote_escape_bytes() {
+        assert_eq!("b\"\"", quote_escape_bytes(b""));
+        assert_eq!("b\"xyZW\"", quote_escape_bytes(b"xyZW"));
+        assert_eq!("b\"aa\\\"bb\"", quote_escape_bytes(b"aa\"bb"));
+        assert_eq!("b\"aa\\r\\n\\tbb\"", quote_escape_bytes(b"aa\r\n\tbb"));
+        assert_eq!(
+            "b\"\\x00\\x01\\x12\\xfe\\xff\"",
+            quote_escape_bytes(b"\x00\x01\x12\xfe\xff")
+        );
+    }
+}