From b18eea05a44478da6860dd52efdfb0d9c61fc09a Mon Sep 17 00:00:00 2001
From: Antros Economides <antroseconomides@hotmail.co.uk>
Date: Mon, 28 Aug 2023 18:32:49 +0300
Subject: [PATCH] Bootstrap in stages

This requires the `bootstrap/1` tag, which we have to fetch explicitly
on the test runners (see
https://github.com/actions/checkout/issues/701).
---
 .github/workflows/graphene_tests.yml |  4 +++-
 bootstrap.sh                         | 17 ++++++++++++++++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/graphene_tests.yml b/.github/workflows/graphene_tests.yml
index 8d914c3b..a2dadae2 100644
--- a/.github/workflows/graphene_tests.yml
+++ b/.github/workflows/graphene_tests.yml
@@ -38,6 +38,8 @@ jobs:
         sudo ./llvm.sh ${{ matrix.llvm-version }}
         sudo apt-get install -y llvm-${{ matrix.llvm-version }}-runtime
     - name: Bootstrap the parser
-      run: ./bootstrap.sh
+      run: |
+        git fetch --tags origin
+        ./bootstrap.sh
     - name: Run tests
       run: python tests/run_tests.py
diff --git a/bootstrap.sh b/bootstrap.sh
index 2a11676f..362be3a8 100755
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -1,4 +1,19 @@
 #!/usr/bin/env bash
 
-# Atm this is easy... it becomes harder once we remove lark
+set -ex
+
+# Attempt to get the current location. Prefer a branch name if available,
+# otherwise fall back to the current commit's hash if we are in "detached HEAD"
+# state.
+git_location=$(git branch --show)
+if [[ "$git_location" == "" ]]; then
+    git_location=$(git rev-parse HEAD)
+fi
+
+# Stage 1; last commit where the Lark parser can parse the native parser.
+git checkout bootstrap/1
 ./glang ./parser/parser.c3 -o ./parser/parser --bootstrap -O3
+
+# Stage 2; build native parser at current commit
+git checkout "$git_location"
+./glang ./parser/parser.c3 -o ./parser/parser -O3