document how the benchmark was produced and add python script used

Author: cosmicexplorer

benches/decompress_sink.rs

@@ -13,7 +13,14 @@ use zip::read::ZipFile;
 use zip::unstable::read::streaming::StreamingArchive;
 use zip::{result::ZipResult, ZipArchive};
 
-/* This contains the compressed text of King Lear from Project Gutenberg, in the public domain. */
+/* This contains the compressed text of King Lear from Project Gutenberg, in the public domain.
+ * It contains the text of King Lear in multiple formats:
+ * 1. Stored (uncompressed)
+ * 2. Deflated (compresslevel=9)
+ * 3. Bzip2 (compresslevel=9)
+ * It contains 50 of each, with 150 entries total. This is generated by the script
+ * tests/data/generate-king-lear-zip.py.
+ */
 fn get_test_data() -> ZipResult<ZipArchive<fs::File>> {
     let path = Path::new(env!("CARGO_MANIFEST_DIR")).join("tests/data/king-lear-compressed.zip");
     let file = fs::File::open(path)?;