feat: add gas diff to CI workflow

.github/workflows/gas-diff.yml

@@ -0,0 +1,57 @@
+name: Report gas diff
+
+on: 
+  workflow_call:
+# on:
+#   push:
+#     branches:
+#       - main
+#   pull_request:
+#     # Optionally configure to run only for changes in specific files. For example:
+#     # paths:
+#     # - src/**
+#     # - test/**
+#     # - foundry.toml
+#     # - remappings.txt
+#     # - .github/workflows/foundry-gas-diff.yml
+
+jobs:
+  compare_gas_reports:
+    name: Compare
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with: 
+          submodules: recursive
+
+      - uses: ./.github/actions/install
+
+      - name: Build contracts
+        run: forge build --sizes
+
+      - name: Check gas snapshots
+        run: forge snapshot --diff
+
+      - name: Run tests
+        run: forge test --gas-report > gasreport.ansi
+        env:
+          # make fuzzing semi-deterministic to avoid noisy gas cost estimation
+          # due to non-deterministic fuzzing (but still use pseudo-random fuzzing seeds)
+          FOUNDRY_FUZZ_SEED: 0x${{ github.event.pull_request.base.sha || github.sha }}
+
+      - name: Compare gas reports
+        uses: Rubilmax/[email protected]
+        with:
+          summaryQuantile: 0.9 # only display the 10% most significant gas diffs in the summary (defaults to 20%)
+          sortCriteria: avg,max # sort diff rows by criteria
+          sortOrders: desc,asc # and directions
+          ignore: test-foundry/**/* # filter out gas reports from specific paths (test/ is included by default)
+        id: gas_diff
+
+      - name: Add gas diff to sticky comment
+        if: github.event_name == 'pull_request' || github.event_name == 'pull_request_target'
+        uses: marocchino/sticky-pull-request-comment@v2
+        with:
+          # delete the comment in case changes no longer impact gas costs
+          delete: ${{ !steps.gas_diff.outputs.markdown }}
+          message: ${{ steps.gas_diff.outputs.markdown }}

.github/workflows/pull_request.yml

@@ -22,4 +22,10 @@ jobs:
   analyse:
     name: Slither analysis
     uses: ./.github/workflows/slither.yml
-    secrets: inherit
+    secrets: inherit
+
+  gas-diff:
+    name: Gas diff
+    uses: ./.github/workflows/gas-diff.yml
+    secrets: inherit
+