add fn Binascii rlecode_hqx rledecode_hqx (RustPython#3809)

Author: yangbeom

Lib/test/test_binascii.py

@@ -220,8 +220,6 @@ def test_hqx(self):
         res = binascii.rledecode_hqx(b)
         self.assertEqual(res, self.rawdata)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_rle(self):
         # test repetition with a repetition longer than the limit of 255
         data = (b'a' * 100 + b'b' + b'c' * 300)

stdlib/src/binascii.rs

@@ -182,6 +182,73 @@ mod decl {
         Ok((*c - 0x20) & 0x3f)
     }
 
+    #[pyfunction]
+    fn rlecode_hqx(s: ArgAsciiBuffer) -> PyResult<Vec<u8>> {
+        const RUNCHAR: u8 = 0x90; // b'\x90'
+        s.with_ref(|buffer| {
+            let len = buffer.len();
+            let mut out_data = Vec::<u8>::with_capacity((len * 2) + 2);
+
+            let mut idx = 0;
+            while idx < len {
+                let ch = buffer[idx];
+
+                if ch == RUNCHAR {
+                    out_data.push(RUNCHAR);
+                    out_data.push(0);
+                    return Ok(out_data);
+                } else {
+                    let mut inend = idx + 1;
+                    while inend < len && buffer[inend] == ch && inend < idx + 255 {
+                        inend += 1;
+                    }
+                    if inend - idx > 3 {
+                        out_data.push(ch);
+                        out_data.push(RUNCHAR);
+                        out_data.push(((inend - idx) % 256) as u8);
+                        idx = inend - 1;
+                    } else {
+                        out_data.push(ch);
+                    }
+                }
+                idx += 1;
+            }
+            Ok(out_data)
+        })
+    }
+
+    #[pyfunction]
+    fn rledecode_hqx(s: ArgAsciiBuffer) -> PyResult<Vec<u8>> {
+        const RUNCHAR: u8 = 0x90; //b'\x90'
+        s.with_ref(|buffer| {
+            let len = buffer.len();
+            let mut out_data = Vec::<u8>::with_capacity(len);
+            let mut idx = 0;
+
+            out_data.push(buffer[idx]);
+            idx += 1;
+
+            while idx < len {
+                if buffer[idx] == RUNCHAR {
+                    if buffer[idx + 1] == 0 {
+                        out_data.push(RUNCHAR);
+                    } else {
+                        let ch = buffer[idx - 1];
+                        let range = buffer[idx + 1];
+                        idx += 1;
+                        for _ in 1..range {
+                            out_data.push(ch);
+                        }
+                    }
+                } else {
+                    out_data.push(buffer[idx]);
+                }
+                idx += 1;
+            }
+            Ok(out_data)
+        })
+    }
+
     #[pyfunction]
     fn a2b_uu(s: ArgAsciiBuffer, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
         s.with_ref(|b| {