Add Rust cross compilation scripts

.github/workflows/common/rust-cross/determine-cross-version.sh

@@ -0,0 +1,15 @@
+set -e
+set -x
+set -o pipefail
+
+VERSION=$1
+
+if [ -z "$VERSION" ]; then
+    JSON=$( curl \
+                --request GET \
+                --header "Authorization: Bearer $GITHUB_TOKEN" \
+                https://api.github.com/repos/cross-rs/cross/releases/latest )
+    VERSION=$( echo "$JSON" | jq -r ".tag_name")
+fi
+
+echo "cross-version=$VERSION" >> $GITHUB_OUTPUT

.github/workflows/common/rust-cross/install-cross-nix.sh

@@ -0,0 +1,18 @@
+set -e
+set -x
+set -o pipefail
+
+CROSS_DIR="$1"
+VERSION="$2"
+
+VERSION_ARGS=""
+if [ -n "$VERSION" ]; then
+    VERSION_ARGS="--tag $VERSION"
+fi
+
+cd "$CROSS_DIR"
+export TARGET=.
+curl --silent --location \
+     https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
+    sh
+./ubi --project cross-rs/cross --matching musl --in . $VERSION_ARGS

.github/workflows/common/rust-cross/perltidyrc.txt

@@ -0,0 +1,22 @@
+-l=78
+-i=4
+-ci=4
+-se
+-b
+-bar
+-boc
+-vt=0
+-vtc=0
+-cti=0
+-pt=1
+-bt=1
+-sbt=1
+-bbt=1
+-nolq
+-npro
+-nsfs
+--blank-lines-before-packages=0
+--opening-hash-brace-right
+--no-outdent-long-comments
+--iterations=2
+-wbb="% + - * / x != == >= <= =~ !~ < > | & >= < = **= += *= &= <<= &&= -= /= |= >>= ||= .= %= ^= x="

.github/workflows/common/rust-cross/precious.toml

@@ -0,0 +1,47 @@
+exclude = [
+  "target",
+]
+
+[commands.perltidy]
+type = "both"
+include = [ "**/*.{pl,pm,t,psgi}" ]
+exclude = "tests/lib/**"
+cmd = [ "perltidy", "--profile=$PRECIOUS_ROOT/perltidyrc" ]
+lint_flags = [ "--assert-tidy", "--no-standard-output", "--outfile=/dev/null" ]
+tidy_flags = [ "--backup-and-modify-in-place", "--backup-file-extension=/" ]
+ok_exit_codes = 0
+lint_failure_exit_codes = 2
+ignore_stderr = "Begin Error Output Stream"
+
+[commands.prettier-md]
+type    = "both"
+include = [ "**/*.md" ]
+cmd     = [ "./node_modules/.bin/prettier", "--no-config", "--print-width", "100", "--prose-wrap", "always" ]
+lint_flags = "--check"
+tidy_flags = "--write"
+ok_exit_codes = 0
+lint_failure_exit_codes = 1
+ignore_stderr = [ "Code style issues" ]
+
+[commands.prettier-yml]
+type    = "both"
+include = [ "**/*.yml" ]
+cmd     = [ "./node_modules/.bin/prettier", "--no-config" ]
+lint_flags = "--check"
+tidy_flags = "--write"
+ok_exit_codes = 0
+lint_failure_exit_codes = 1
+ignore_stderr = [ "Code style issues" ]
+
+[commands.omegasort-gitignore]
+type = "both"
+include = "**/.gitignore"
+cmd = [ "omegasort", "--sort", "path", "--unique" ]
+lint_flags = "--check"
+tidy_flags = "--in-place"
+ok_exit_codes = 0
+lint_failure_exit_codes = 1
+ignore_stderr = [
+    "The .+ file is not sorted",
+    "The .+ file is not unique",
+]

.github/workflows/common/rust-cross/set-build-command.sh

@@ -0,0 +1,9 @@
+set -e
+set -x
+
+CROSS_DIR="$1"
+if [ -f "$CROSS_DIR/cross" ]; then
+    echo "build-command=$CROSS_DIR/cross" >> $GITHUB_OUTPUT
+else
+    echo "build-command=cargo" >> $GITHUB_OUTPUT
+fi

.github/workflows/common/rust-cross/set-cross-compile.sh

@@ -0,0 +1,22 @@
+set -e
+set -x
+
+TARGET="$1"
+
+# On macOS and Windows, we can cross-compile to all possible targets without
+# using cross.
+if uname -a | grep --quiet --extended-regexp -i "darwin|msys|windows"; then
+    echo "needs-cross=false" >> $GITHUB_OUTPUT
+    exit 0
+fi
+
+# On Linux, we should be able to cross-compile to i586 and i686, but in
+# practice this fails with some crates, notably openssl with the "vendored"
+# feature. This feature makes it compile openssl itself, which fails without
+# cross.
+if echo "$TARGET" | grep --quiet --extended-regexp -i 'x86_64.+linux-(gnu|musl)'; then
+    echo "needs-cross=false" >> $GITHUB_OUTPUT
+    exit 0
+fi
+
+echo "needs-cross=true" >> $GITHUB_OUTPUT

.github/workflows/common/rust-cross/set-cross-dir.sh

@@ -0,0 +1,4 @@
+set -e
+set -x
+
+echo "cross-dir=$RUNNER_TEMP" >> $GITHUB_OUTPUT

.github/workflows/common/rust-cross/strip-binary.sh

@@ -0,0 +1,42 @@
+set -e
+set -x
+
+TARGET=$1
+did_strip=""
+
+strip_binary () {
+    if [[ $( uname -s ) =~ "Darwin" ]]; then
+        stripped=$(
+            find "$1" -maxdepth 1 -type f -perm +111 | while read exe; do
+                strip "$exe"
+                echo "stripped $exe"
+            done
+        )
+    else
+        stripped=$(
+            find "$1" -maxdepth 1 -type f -executable | while read exe; do
+                strip "$exe"
+                echo "stripped $exe"
+            done
+        )
+    fi
+
+    if [ -z "$stripped" ]; then
+        echo "Could not find any binaries to strip in $1"
+    else
+        did_strip="true"
+    fi
+}
+
+for type in debug release; do
+    if [ -d "target/$TARGET/$type" ]; then
+        strip_binary "target/$TARGET/$type"
+    elif [ -d "target/$type" ]; then
+        strip_binary "target/$type"
+    fi
+done
+
+if [ -z "$did_strip" ]; then
+    echo "No binaries were stripped"
+    exit 1
+fi

pallets/capacity/src/lib.rs

@@ -48,8 +48,6 @@
 	missing_docs
 )]
 
-// REMOVE: need to touch rs file for testing
-
 use frame_support::{
 	ensure,
 	traits::{