pkgs: lustrate: initial commit

4 files changed, 133 insertions, 0 deletions

diff --git a/pkgs/default.nix b/pkgs/default.nix
index cfc0dda..252eb92 100644
--- a/pkgs/default.nix
+++ b/pkgs/default.nix
@@ -14,6 +14,7 @@ in {
   increment-zone-serials = callPackage ./increment-zone-serials {};
   ipxe = callPackage ./ipxe/default.nix {};
   kbuild-standalone = callPackage ./kbuild-standalone.nix {};
+  lustrate = callPackage ./lustrate {};
   mssql-tools = callPackage ./mssql-tools.nix {};
   oregano = callPackage ./oregano {};
   pass-bcr = callPackage ./pass-bcr {};
diff --git a/pkgs/lustrate/default.nix b/pkgs/lustrate/default.nix
new file mode 100644
index 0000000..cf0a322
--- /dev/null
+++ b/pkgs/lustrate/default.nix
@@ -0,0 +1,6 @@
+{writeShellApplication, ...}:
+writeShellApplication {
+  name = "lustrate";
+  runtimeInputs = [];
+  text = import ./filters.nix + builtins.readFile ./lustrate.sh;
+}
diff --git a/pkgs/lustrate/filters.nix b/pkgs/lustrate/filters.nix
new file mode 100644
index 0000000..1bb3788
--- /dev/null
+++ b/pkgs/lustrate/filters.nix
@@ -0,0 +1 @@
+# This file has been lustrated.
diff --git a/pkgs/lustrate/lustrate.sh b/pkgs/lustrate/lustrate.sh
new file mode 100644
index 0000000..8435f61
--- /dev/null
+++ b/pkgs/lustrate/lustrate.sh
@@ -0,0 +1,125 @@
+LUSTRATE="$(realpath "$0")"
+
+usage() {
+    echo "Usage: $LUSTRATE <src repo> <dst repo>" >&2
+    exit 1
+}
+
+filter=""
+set_filter() {
+    [ -z "$filter" ] || usage
+    filter="$1"
+}
+
+src_repo=""
+dst_repo=""
+
+positional_arg() {
+    if [ -z "$src_repo" ]; then
+        src_repo="$1"
+    elif [ -z "$dst_repo" ]; then
+        dst_repo="$1"
+    else
+        usage
+    fi
+}
+
+no_more_options=""
+while [ $# -gt 0 ]; do
+    if [ -n "$no_more_options" ]; then
+        positional_arg "$1"
+    else
+        case "$1" in
+            "--tree")
+                set_filter tree
+                ;;
+
+            "--msg")
+                set_filter msg
+                ;;
+
+            "--")
+                no_more_options=1
+                ;;
+
+            *)
+                positional_arg "$1"
+        esac
+    fi
+
+    shift
+done
+
+if [ -n "$filter" ]; then
+    case "$filter" in
+        "tree")
+            for path in "${filtered_paths[@]}"; do
+                rm -frv -- "$path"
+            done
+
+            for path in "${cleared_dirs[@]}"; do
+                if [ -d "$path" ]; then
+                   rm -frv -- "$path"
+                   mkdir "$path"
+                   echo "# This directory has been lustrated." >"$path/README.md"
+               fi
+            done
+
+            for path in "${cleared_files[@]}"; do
+                if [ -f "$path" ]; then
+                   rm -frv -- "$path"
+                   echo "# This file has been lustrated." >"$path"
+               fi
+            done
+
+            # This prevents the script from matching itself
+            LUSTRATE="lustrate"
+            find . -type f -exec sed -i "/#+$LUSTRATE/, /#-$LUSTRATE/d" -- {} \;
+            ;;
+
+        "msg")
+            sed -e "$LUSTRATE_MSG_SED_SCRIPT"
+            ;;
+
+        *)
+            usage
+            ;;
+    esac
+
+    exit
+fi
+
+if [ -z "$src_repo" ] || [ -z "$dst_repo" ]; then
+    usage
+fi
+
+SCRIPT="$extra_msg_script"
+for regex in "${cleared_msg_regexes[@]}"; do
+    SCRIPT="$SCRIPT;s/$regex/\1\[lustrated\]\2/g"
+done
+
+# Special case for flake lock updates
+SCRIPT="$SCRIPT;/Flake lock file updates:/,\$d"
+
+export LUSTRATE_MSG_SED_SCRIPT="$SCRIPT"
+export FILTER_BRANCH_SQUELCH_WARNING=1
+
+trap 'rm -fr -- "$tmp_repo"' EXIT
+tmp_repo="$(mktemp -d)"
+
+git -C "$tmp_repo" -c init.defaultBranch=master init
+git -C "$tmp_repo" fetch -- "$(realpath "$src_repo")"
+
+REF_PWD="$PWD"
+cd "$tmp_repo"
+
+git reset --hard FETCH_HEAD
+git clean -dfx
+
+git filter-branch \
+    --tree-filter "$LUSTRATE --tree" \
+    --msg-filter  "$LUSTRATE --msg" \
+    --prune-empty
+
+cd "$REF_PWD"
+mv -T -- "$tmp_repo" "$dst_repo"