Fix compact gate build errors

This fixes private-attribution#1301 and cleans up assertions

ipa-core/Cargo.toml

@@ -16,11 +16,12 @@ default = [
     "stall-detection",
     "aggregate-circuit",
     "ipa-prf",
-    "ipa-step/string-step",
+    "string-step",
 ]
 cli = ["comfy-table", "clap"]
-# Enabling compact gates disables any tests that rely on descriptive gates.
-compact-gate = ["ipa-step/string-step"]
+# Enable compact gate optimization
+compact-gate = []
+string-step = ["ipa-step/string-step"]
 disable-metrics = []
 # TODO move web-app to a separate crate. It adds a lot of build time to people who mostly write protocols
 # TODO Consider moving out benches as well
@@ -82,7 +83,6 @@ ipa-step = { version = "*", path = "../ipa-step" }
 ipa-step-derive = { version = "*", path = "../ipa-step-derive" }
 
 aes = "0.8.3"
-assertions = "0.1.0"
 async-trait = "0.1.79"
 async-scoped = { version = "0.9.0", features = ["use-tokio"], optional = true }
 axum = { version = "0.7.5", optional = true, features = ["http2", "macros"] }

ipa-core/build.rs

@@ -44,7 +44,7 @@ fn main() {
     // https://docs.rs/tectonic_cfg_support/latest/tectonic_cfg_support/struct.TargetConfiguration.html
     cfg_aliases! {
         compact_gate: { feature = "compact-gate" },
-        descriptive_gate: { not(compact_gate) },
+        descriptive_gate: { all(not(feature = "compact-gate"), feature = "string-step") },
         unit_test: { all(not(feature = "shuttle"), feature = "in-memory-infra", descriptive_gate) },
         web_test: { all(not(feature = "shuttle"), feature = "real-world-infra") },
     }

ipa-core/src/protocol/ipa_prf/mod.rs

@@ -733,7 +733,7 @@ pub mod tests {
     }
 }
 
-#[cfg(all(test, all(feature = "compact-gate", feature = "in-memory-infra")))]
+#[cfg(all(test, all(compact_gate, feature = "in-memory-infra")))]
 mod compact_gate_tests {
     use ipa_step::{CompactStep, StepNarrow};
 

ipa-core/src/report/hybrid.rs

@@ -5,14 +5,14 @@ use std::{
     ops::{Add, Deref},
 };
 
-use assertions::const_assert;
 use bytes::{BufMut, Bytes};
 use generic_array::{ArrayLength, GenericArray};
 use hpke::Serializable as _;
 use rand_core::{CryptoRng, RngCore};
 use typenum::{Sum, Unsigned, U16};
 
 use crate::{
+    const_assert_eq,
     error::{BoxError, Error},
     ff::{boolean_array::BA64, Serializable},
     hpke::{
@@ -407,14 +407,9 @@ impl UniqueBytes for EncryptedHybridReport {
 }
 
 impl UniqueTag {
-    fn _compile_check() {
-        // This will vaild at compile time if TAG_SIZE doesn't match U16
-        // the macro expansion needs to be wrapped in a function
-        const_assert!(TAG_SIZE == 16);
-    }
-
     // Function to attempt to create a UniqueTag from a UniqueBytes implementor
     pub fn from_unique_bytes<T: UniqueBytes>(item: &T) -> Self {
+        const_assert_eq!(16, TAG_SIZE);
         UniqueTag {
             bytes: item.unique_bytes(),
         }