dev: update scripts to push subrepos

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

dev/push-subrepos.sh

@@ -1,8 +1,59 @@
 #!/usr/bin/env bash
-set -exuo pipefail
+set -euo pipefail
 cd "$(dirname "${BASH_SOURCE[0]}")"/..
 
-./dev/update-subrepos.sh
-git subtree push --prefix libs/glfw mach-glfw main
-git subtree push --prefix libs/gpu-dawn mach-gpu-dawn main
-git subtree push --prefix libs/freetype mach-freetype main
+push_subrepo() {
+    local project=$1
+
+    echo "    ----------------------------------------------------------------------------"
+    echo "    | 🚀🐒 Preparing: mach-$project"
+    echo "    ----------------------------------------------------------------------------"
+    cp -R staging-clean staging/
+    cd staging/
+
+    # Rewrite e.g. libs/freetype/ -> freetype/ so we have Git history for that subrepo in one path
+    # only (git subtree cannot follow renames.) For glfw, gpu-dawn, and freetype they were in the
+    # root before being under libs/ and so this is required to generate the proper history.
+    if [[ "$project" == "glfw" ]]; then
+        # glfw has an unfortunately non-linear history, and so we can't preserve commit hashes
+        # or else the subtree push cannot rebuild history properly.
+        git filter-repo --force \
+            --path $project \
+            --path "libs/$project" \
+            --path-rename libs/$project:$project
+    else
+        git filter-repo --force \
+            --preserve-commit-hashes \
+            --path $project \
+            --path "libs/$project" \
+            --path-rename libs/$project:$project
+    fi
+
+    # Push changes to the external subrepo.
+    if [ -n "${GITHUB_ACTIONS:-}" ]; then
+        git remote add -f "mach-$project" "https://slimsag:$ACCESS_TOKEN@github.com/hexops/mach-$project" || true
+    else
+        git remote add -f "mach-$project" "git@github.com:hexops/mach-$project" || true
+    fi
+    git fetch "mach-$project"
+
+    echo "    ----------------------------------------------------------------------------"
+    echo "    | 🚀🐒 Pushing: mach-$project"
+    echo "    ----------------------------------------------------------------------------"
+    git subtree push --prefix "$project" "mach-$project" main
+
+    cd ..
+    rm -rf staging/
+    echo "    ----------------------------------------------------------------------------"
+    echo "    | 🚀🐒 Finished: mach-$project"
+    echo "    ----------------------------------------------------------------------------"
+}
+
+rm -rf staging-clean/ staging/
+git clone https://github.com/hexops/mach staging-clean
+
+push_subrepo 'glfw'
+push_subrepo 'gpu-dawn'
+push_subrepo 'freetype'
+
+rm -rf staging-clean