From f4d0a9230de40a3710d06e941dc0e7e9645f8d7b Mon Sep 17 00:00:00 2001
From: Aumetra Weisman <aumetra@cryptolab.net>
Date: Tue, 19 Mar 2024 15:10:21 +0100
Subject: [PATCH] Implement `Stringer` interface, skip `HashMap` on Rust side

---
 internal/api/lib_test.go | 43 ++++++++++++++++++++++++++++++----------
 libwasmvm/src/cache.rs   |  7 +++----
 types/checksum.go        |  2 +-
 types/types.go           |  7 ++++++-
 4 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/internal/api/lib_test.go b/internal/api/lib_test.go
index 27a7406e4..d039f60f8 100644
--- a/internal/api/lib_test.go
+++ b/internal/api/lib_test.go
@@ -389,7 +389,7 @@ func TestGetPinnedMetrics(t *testing.T) {
 	// GetMetrics 1
 	metrics, err := GetPinnedMetrics(cache)
 	require.NoError(t, err)
-	assert.Equal(t, &types.PinnedMetrics{PerModule: make(map[string]types.PerModuleMetrics, 0)}, metrics)
+	assert.Equal(t, &types.PinnedMetrics{PerModule: make([]types.PerModuleEntry, 0)}, metrics)
 
 	// Store contract 1
 	wasm, err := os.ReadFile("../../testdata/hackatom.wasm")
@@ -409,17 +409,34 @@ func TestGetPinnedMetrics(t *testing.T) {
 	err = Pin(cache, cyberpunkChecksum)
 	require.NoError(t, err)
 
-	checksumStr := types.Checksum(checksum).EncodeHex()
-	cyberpunkChecksumStr := types.Checksum(cyberpunkChecksum).EncodeHex()
+	checksumStr := types.Checksum(checksum).String()
+	cyberpunkChecksumStr := types.Checksum(cyberpunkChecksum).String()
+
+	findMetrics := func(list []types.PerModuleEntry, checksum string) *types.PerModuleMetrics {
+		found := (*types.PerModuleMetrics)(nil)
+
+		for _, structure := range list {
+			if structure.Name == checksum {
+				found = &structure.Metrics
+				break
+			}
+		}
+
+		return found
+	}
 
 	// GetMetrics 2
 	metrics, err = GetPinnedMetrics(cache)
 	require.NoError(t, err)
 	assert.Equal(t, 2, len(metrics.PerModule))
-	assert.Equal(t, uint32(0), metrics.PerModule[checksumStr].Hits)
-	assert.NotEqual(t, uint32(0), metrics.PerModule[checksumStr].Size)
-	assert.Equal(t, uint32(0), metrics.PerModule[cyberpunkChecksumStr].Hits)
-	assert.NotEqual(t, uint32(0), metrics.PerModule[cyberpunkChecksumStr].Size)
+
+	hackatomMetrics := findMetrics(metrics.PerModule, checksumStr)
+	cyberpunkMetrics := findMetrics(metrics.PerModule, cyberpunkChecksumStr)
+
+	assert.Equal(t, uint32(0), hackatomMetrics.Hits)
+	assert.NotEqual(t, uint32(0), hackatomMetrics.Size)
+	assert.Equal(t, uint32(0), cyberpunkMetrics.Hits)
+	assert.NotEqual(t, uint32(0), cyberpunkMetrics.Size)
 
 	// Instantiate 1
 	gasMeter := NewMockGasMeter(TESTING_GAS_LIMIT)
@@ -437,10 +454,14 @@ func TestGetPinnedMetrics(t *testing.T) {
 	metrics, err = GetPinnedMetrics(cache)
 	require.NoError(t, err)
 	assert.Equal(t, 2, len(metrics.PerModule))
-	assert.Equal(t, uint32(1), metrics.PerModule[checksumStr].Hits)
-	assert.NotEqual(t, uint32(0), metrics.PerModule[checksumStr].Size)
-	assert.Equal(t, uint32(0), metrics.PerModule[cyberpunkChecksumStr].Hits)
-	assert.NotEqual(t, uint32(0), metrics.PerModule[cyberpunkChecksumStr].Size)
+
+	hackatomMetrics = findMetrics(metrics.PerModule, checksumStr)
+	cyberpunkMetrics = findMetrics(metrics.PerModule, cyberpunkChecksumStr)
+
+	assert.Equal(t, uint32(1), hackatomMetrics.Hits)
+	assert.NotEqual(t, uint32(0), hackatomMetrics.Size)
+	assert.Equal(t, uint32(0), cyberpunkMetrics.Hits)
+	assert.NotEqual(t, uint32(0), cyberpunkMetrics.Size)
 }
 
 func TestInstantiate(t *testing.T) {
diff --git a/libwasmvm/src/cache.rs b/libwasmvm/src/cache.rs
index 7f84662b3..5f38affd2 100644
--- a/libwasmvm/src/cache.rs
+++ b/libwasmvm/src/cache.rs
@@ -1,4 +1,4 @@
-use std::collections::{BTreeSet, HashMap};
+use std::collections::BTreeSet;
 use std::convert::TryInto;
 use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::str::from_utf8;
@@ -433,7 +433,7 @@ impl From<cosmwasm_vm::PerModuleMetrics> for PerModuleMetrics {
 
 #[derive(Serialize)]
 struct PinnedMetrics {
-    per_module: HashMap<Checksum, PerModuleMetrics>,
+    per_module: Vec<(Checksum, PerModuleMetrics)>,
 }
 
 impl From<cosmwasm_vm::PinnedMetrics> for PinnedMetrics {
@@ -441,8 +441,7 @@ impl From<cosmwasm_vm::PinnedMetrics> for PinnedMetrics {
         Self {
             per_module: value
                 .per_module
-                .iter()
-                .cloned()
+                .into_iter()
                 .map(|(checksum, metrics)| (checksum, metrics.into()))
                 .collect(),
         }
diff --git a/types/checksum.go b/types/checksum.go
index bb472e317..2f74224d9 100644
--- a/types/checksum.go
+++ b/types/checksum.go
@@ -10,7 +10,7 @@ import (
 // The length of a checksum must always be ChecksumLen.
 type Checksum []byte
 
-func (cs Checksum) EncodeHex() string {
+func (cs Checksum) String() string {
 	return hex.EncodeToString(cs)
 }
 
diff --git a/types/types.go b/types/types.go
index 4113f2313..904e67b3e 100644
--- a/types/types.go
+++ b/types/types.go
@@ -196,8 +196,13 @@ type PerModuleMetrics struct {
 	Size uint64 `msgpack:"size"`
 }
 
+type PerModuleEntry struct {
+	Name    string
+	Metrics PerModuleMetrics
+}
+
 type PinnedMetrics struct {
-	PerModule map[string]PerModuleMetrics `msgpack:"per_module"`
+	PerModule []PerModuleEntry `msgpack:"per_module,as_array"`
 }
 
 func (pm *PinnedMetrics) UnmarshalMessagePack(data []byte) error {