Return EOF error if writer returns Ok(0)

src/lib.rs

@@ -248,8 +248,10 @@ pub fn BrotliDecompressCustomIoCustomDict<ErrType,
             Err(e) => {
               return Result::Err(e);
             },
+            Ok(0) => {
+              return Result::Err(unexpected_eof_error_constant);
+            }
             Ok(cur_written) => {
-              assert_eq!(cur_written == 0, false); // not allowed by the contract
               total_written += cur_written;
             }
           }
@@ -280,8 +282,10 @@ pub fn BrotliDecompressCustomIoCustomDict<ErrType,
             return Result::Err(e);
           },
           // CustomResult::Transient(e) => continue,
+          Ok(0) => {
+            return Result::Err(unexpected_eof_error_constant);
+          }
           Ok(cur_written) => {
-            assert_eq!(cur_written == 0, false); // not allowed by the contract
             total_written += cur_written;
           }
         }

src/test.rs

@@ -268,3 +268,18 @@ fn test_early_eof() {
   }
   assert_eq!(input_offset, input.len());
 }
+
+#[test]
+#[cfg(feature="std")]
+fn test_run_out_of_writer_space() {
+  // this is a valid compression of [0u8; 2048];
+  let compression = [27, 255, 7, 0, 36, 0, 194, 177, 64, 114, 7];
+  // output buffer doesn't have enough space
+  let mut output_buffer = [0u8; 2047];
+
+  super::BrotliDecompress(
+    &mut io::Cursor::new(compression),
+    &mut io::Cursor::new(&mut output_buffer[..]),
+  )
+  .unwrap_err();
+}