fix(stdlib): Avoid WASI random_get in Hash stdlib during module start…

…up (#2078)

stdlib/hash.gr

@@ -43,9 +43,15 @@ from "wasi/random" include Random
 from "result" include Result
 
 @unsafe
-let seed = {
+let mut seed = 0n
+
+@unsafe
+let initalize = () => {
+  // Delay initialization to the first call to `hash` to prevent WASI calls
+  // during startup
   let random = Random.random()
-  coerceNumberToWasmI32(Result.unwrap(random))
+  seed = coerceNumberToWasmI32(Result.unwrap(random))
+  seed
 }
 
 @unsafe
@@ -239,6 +245,8 @@ let rec hashOne = (val, depth) => {
  *
  * @param anything: The value to hash
  * @returns A hash for the given value
+ * 
+ * @throws Failure(String): If WASI random_get fails
  *
  * @example assert Hash.hash(1) == Hash.hash(1)
  * @example assert Hash.hash("Hello World") == Hash.hash("Hello World")
@@ -247,7 +255,11 @@ let rec hashOne = (val, depth) => {
  */
 @unsafe
 provide let hash = anything => {
-  h = seed
+  h = if (WasmI32.eqz(seed)) {
+    initalize()
+  } else {
+    seed
+  }
 
   hashOne(WasmI32.fromGrain(anything), 0n)
   finalize(0n)

stdlib/hash.md

@@ -50,6 +50,12 @@ Returns:
 |----|-----------|
 |`Number`|A hash for the given value|
 
+Throws:
+
+`Failure(String)`
+
+* If WASI random_get fails
+
 Examples:
 
 ```grain