Prevent Rust feature bleed

rust-features.sh

@@ -0,0 +1,96 @@
+#!/usr/bin/env bash
+
+##############################################################################
+#
+# This script checks that crates to not carelessly enable features that
+# should stay disabled. It's important to check that since features
+# are used to gate specific functionality which should only be enabled
+# when the feature is explicitly enabled.
+#
+# Invocation scheme:
+# 	./rust-features.sh <CARGO-ROOT-PATH>
+#
+# Example:
+# 	./rust-features.sh path/to/substrate
+#
+# The steps of this script:
+#   1. Check that all required dependencies are installed.
+#   2. Check that all rules are fullfilled for the whole workspace. If not:
+#   4. Check all crates to find the offending ones.
+#   5. Print all offending crates and exit with code 1.
+#
+##############################################################################
+
+set -eu
+
+# Check that cargo, grep and egrep are installed.
+command -v cargo >/dev/null 2>&1 || { echo >&2 "cargo is required but not installed. Aborting."; exit 1; }
+command -v grep >/dev/null 2>&1 || { echo >&2 "grep is required but not installed. Aborting."; exit 1; }
+command -v egrep >/dev/null 2>&1 || { echo >&2 "egrep is required but not installed. Aborting."; exit 1; }
+
+CARGO_ROOT=$1
+cd "$CARGO_ROOT"
+
+# NOTE: The features should be separated by a single `,`.
+declare -a FEATURE_RULES=(
+	"default,std never implies feature runtime-benchmarks"
+	"default,std never implies feature try-runtime"
+)
+
+function check_does_not_imply() {
+	ENABLED=$1
+	STAYS_DISABLED=$2
+	echo "📏 Checking that $ENABLED does not imply $STAYS_DISABLED ..."
+
+	RET=0
+	# Check if the forbidden feature is enabled anywhere in the workspace.
+	cargo tree --no-default-features --locked --workspace -e features --features "$ENABLED" | grep -q "feature \"$STAYS_DISABLED\"" || RET=$?
+	if [ $RET -ne 0 ]; then
+		echo "✅ $ENABLED does not imply $STAYS_DISABLED in the workspace"
+		return
+	else
+		echo "❌ $ENABLED implies $STAYS_DISABLED in the workspace"
+	fi
+
+	# Find all Cargo.toml files but exclude the root one since we know that it is broken.
+	CARGOS=`find . -name Cargo.toml -not -path ./Cargo.toml`
+	FAILED=0
+	PASSED=0
+	# number of all cargos
+	echo "🔍 Checking individual crates - this takes some time."
+
+	for CARGO in $CARGOS; do
+		RET=0
+		OUTPUT=$(cargo tree --no-default-features --locked --offline -e features --features $ENABLED --manifest-path $CARGO 2>&1 || true)
+		IS_NOT_SUPPORTED=$(echo $OUTPUT | grep -q "not supported for packages in this workspace" || echo $?)
+
+		if [ $IS_NOT_SUPPORTED -eq 0 ]; then
+			# This case just means that the pallet does not support the
+			# requested feature which is fine.
+			PASSED=$((PASSED+1))
+		elif echo "$OUTPUT" | grep -q "feature \"$STAYS_DISABLED\""; then
+			echo "❌ Violation in $CARGO by dependency:"
+			# Best effort hint for which dependency needs to be fixed.
+			echo "$OUTPUT" | grep -w "feature \"$STAYS_DISABLED\"" | head -n 1
+			FAILED=$((FAILED+1))
+		else
+			PASSED=$((PASSED+1))
+		fi
+	done
+
+	TOTAL=$((PASSED + FAILED))
+	echo "Checked $TOTAL crates in total of which $FAILED failed and $PASSED passed."
+	echo "Exiting with code 1"
+	exit 1
+}
+
+for RULE in "${FEATURE_RULES[@]}"; do
+    read -a splits <<< "$RULE"
+	ENABLED=${splits[0]}
+	STAYS_DISABLED=${splits[4]}
+	# Split ENABLED at , and check each one.
+	IFS=',' read -ra ENABLED_SPLIT <<< "$ENABLED"
+	for ENABLED_SPLIT in "${ENABLED_SPLIT[@]}"; do
+		check_does_not_imply "$ENABLED_SPLIT" "$STAYS_DISABLED"
+	done	
+done