some refactoring

src/math_app.rs

@@ -160,13 +160,10 @@ impl MathApp {
 						assume(!cached_data.is_empty());
 					}
 
-					if commit == build::SHORT_COMMIT {
+					if commit == build::SHORT_COMMIT.chars().map(|c| c as u8).collect::<Vec<u8>>().as_slice() {
 						tracing::info!("Reading decompression cache. Bytes: {}", cached_data.len());
 						return Some(cached_data.to_vec());
 					} else {
-						tracing::info!("Decompression cache are invalid (build: {}, previous: {})", build::SHORT_COMMIT, commit);
-
-						// is invalid
 						None
 					}
 				}
@@ -179,7 +176,8 @@ impl MathApp {
 					}
 
 					tracing::info!("Setting decompression cache");
-					let saved_data = &crate::misc::hashed_storage_create(&build::SHORT_COMMIT.as_bytes(), data);
+					let commit: [u8; crate::misc::HASH_LENGTH] = unsafe { build::SHORT_COMMIT.as_bytes().try_into().unwrap_unchecked() };
+					let saved_data = &crate::misc::hashed_storage_create(commit, data);
 					tracing::info!("Bytes: {}", saved_data.len());
 					get_localstorage().set_item(DATA_NAME, saved_data).expect("failed to set local storage cache");
 				}
@@ -200,13 +198,11 @@ impl MathApp {
 						assume(!func_data.is_empty());
 					}
 
-					if commit == build::SHORT_COMMIT {
+					if commit == build::SHORT_COMMIT.chars().map(|c| c as u8).collect::<Vec<u8>>().as_slice() {
 						tracing::info!("Reading previous function data");
 						let function_manager: FunctionManager = bincode::deserialize(&func_data).ok()?;
 						return Some(function_manager);
 					} else {
-						tracing::info!("Previous functions are invalid due to differing commits (build: {}, previous: {})", build::SHORT_COMMIT, commit);
-						// is invalid
 						None
 					}
 				}
@@ -619,10 +615,15 @@ impl App for MathApp {
 				{
 					tracing::info!("Setting current functions");
 					let saved_data = &crate::misc::hashed_storage_create(
-						&build::SHORT_COMMIT
+						unsafe {
-							.chars()
+							build::SHORT_COMMIT
-							.map(|c| c as u8)
+								.chars()
-							.collect::<Vec<u8>>(),
+								.map(|c| c as u8)
+								.collect::<Vec<u8>>()
+								.as_slice()
+								.try_into()
+								.unwrap_unchecked()
+						},
 						bincode::serialize(&self.functions).unwrap().as_slice(),
 					);
 					// tracing::info!("Bytes: {}", saved_data.len());

src/misc.rs

@@ -311,18 +311,15 @@ pub fn almost_variable(x: f64) -> Option<char> {
 pub const HASH_LENGTH: usize = 8;
 
 #[allow(dead_code)]
-pub fn hashed_storage_create(hash: &[u8], data: &[u8]) -> String {
+pub fn hashed_storage_create(hash: [u8; HASH_LENGTH], data: &[u8]) -> String {
-	debug_assert_eq!(hash.len(), HASH_LENGTH);
 	debug_assert!(!data.is_empty());
 
 	unsafe {
 		assume(!data.is_empty());
-		assume(hash.len() == HASH_LENGTH);
-		assume(!hash.is_empty());
 	}
 
 	// cannot use `from_utf8` seems to break on wasm. no clue why
-	[hash, data]
+	[&hash, data]
 		.concat()
 		.iter()
 		.map(|b| *b as char)
@@ -330,7 +327,7 @@ pub fn hashed_storage_create(hash: &[u8], data: &[u8]) -> String {
 }
 
 #[allow(dead_code)]
-pub fn hashed_storage_read(data: String) -> (String, Vec<u8>) {
+pub fn hashed_storage_read(data: String) -> ([u8; HASH_LENGTH], Vec<u8>) {
 	debug_assert!(data.len() > HASH_LENGTH);
 	unsafe {
 		assume(!data.is_empty());
@@ -351,7 +348,7 @@ pub fn hashed_storage_read(data: String) -> (String, Vec<u8>) {
 	}
 
 	(
-		hash.iter().map(|c| *c as char).collect::<String>(),
+		unsafe { hash.try_into().unwrap_unchecked() },
 		cached_data.to_vec(),
 	)
 }

tests/misc.rs

@@ -97,9 +97,15 @@ fn hashed_storage() {
 		.chars()
 		.map(|c| c as u8)
 		.collect::<Vec<u8>>();
-	let storage = hashed_storage_create(commit.as_slice(), data.as_slice());
+	let storage = hashed_storage_create(
+		commit
+			.as_slice()
+			.try_into()
+			.expect("cannot turn into [u8; 8]"),
+		data.as_slice(),
+	);
 
 	let read = hashed_storage_read(storage);
-	assert_eq!(read.0.chars().map(|c| c as u8).collect::<Vec<u8>>(), commit);
+	assert_eq!(read.0.to_vec(), commit);
 	assert_eq!(read.1, data);
 }