Add e2e test for nested squashing commits

e2e/evolve/nested/evolve_squash.txt

@@ -0,0 +1,135 @@
+# Evolve resolves commit graph after squashing commits
+# =====================================================
+
+# --- SETUP ---
+
+# Add directory with `git` executable to PATH
+env PATH=$PATH${:}/usr/bin/
+
+# Specify commit timestamp so commit hashes are fixed.
+env GIT_COMMITTER_DATE='01 Jan 2023 00:00:00 UTC'
+
+# Specify the test interactive sequence editor program (used in `git rebase -i`).
+env GIT_SEQUENCE_EDITOR='seq_editor'
+
+# Specify the test interactive editor program.
+env GIT_EDITOR='editor'
+
+# The test interactive editor should paste the instructions in `SEQ_EDITOR_INPUT`
+# into Git's instruction sheet.
+env SEQ_EDITOR_INPUT='.git/tree/rebase-instructs'
+
+# The test interactive editor should use the contents in `EDITOR_INPUT`.
+env EDITOR_INPUT='.git/tree/squashed-commit-name'
+
+# Setup the Git repository
+exec git init
+exec git config user.email "[email protected]"
+exec git config user.name "Test"
+exec write_file README.txt readme
+exec git add .
+exec git commit -m 'initial commit' --date $GIT_COMMITTER_DATE
+
+# BUG: This commit is needed to prevent a nil pointer dereference (getting the
+# parent of an initial commit). Fix the algorithm and remove this extra commit.
+exec write_file dummy.txt dummy
+exec git add .
+exec git commit -m 'Add dummy.txt' --date $GIT_COMMITTER_DATE
+
+
+# Initial:
+#
+#  [master] ─── (sceptile) ─── (grovyle) ─── [treecko] ─┬─ [turtwig]
+#                                                       ├─ [chimchar]
+#                                                       └─ [piplup]
+#
+#
+# Action:
+#  - Squash [treecko] into a single commit
+#
+# Result:
+#
+#  [master] ─── [treecko] ─┬─ [turtwig]
+#                          ├─ [chimchar]
+#                          └─ [piplup]
+
+# Add commits to treecko branch
+exec git checkout -b treecko
+
+exec write_file sceptile.txt sceptile
+exec git add .
+exec git commit -m 'Add sceptile.txt' --date $GIT_COMMITTER_DATE
+
+exec write_file grovyle.txt grovyle
+exec git add .
+exec git commit -m 'Add grovyle.txt' --date $GIT_COMMITTER_DATE
+
+exec write_file treecko.txt treecko
+exec git add .
+exec git commit -m 'Add treecko.txt' --date $GIT_COMMITTER_DATE
+
+
+# Add commits to turtwig branch
+exec git checkout -b turtwig
+
+exec write_file turtwig.txt turtwig
+exec git add .
+exec git commit -m 'Add turtwig.txt' --date $GIT_COMMITTER_DATE
+
+
+# Add commits to chimchar branch
+exec git checkout treecko
+exec git checkout -b chimchar
+
+exec write_file chimchar.txt chimchar
+exec git add .
+exec git commit -m 'Add chimchar.txt' --date $GIT_COMMITTER_DATE
+
+
+# Add commits to piplup branch
+exec git checkout treecko
+exec git checkout -b piplup
+
+exec write_file piplup.txt piplup
+exec git add .
+exec git commit -m 'Add piplup.txt' --date $GIT_COMMITTER_DATE
+
+
+# Initialize git-tree
+exec git-tree init
+
+# Squash some commits in the graph.
+exec git checkout treecko
+exec git rebase -i HEAD~3
+
+
+# --- TEST ---
+
+# Run evolve
+exec git-tree evolve
+
+# BUG: The old commit still exists in the repository, since it's pointed to by
+# branch `git-tree-root`. Fix `git-tree-root` target instead of dropping git-tree.
+exec git-tree drop
+
+# Compare the git log
+exec git log --oneline --graph --all --decorate
+cp stdout .git/actual-log
+exec compare .git/actual-log .git/golden-log
+
+
+-- .git/tree/rebase-instructs --
+pick f2649a5 Add sceptile.txt
+squash 2e38457 Add grovyle.txt
+squash 707b83d Add treecko.txt
+-- .git/tree/squashed-commit-name --
+Add treecko.txt
+-- .git/golden-log --
+* 2e7f178 (chimchar) Add chimchar.txt
+| * 7693991 (piplup) Add piplup.txt
+|/  
+| * 5dbe0f7 (turtwig) Add turtwig.txt
+|/  
+* 8d819d7 (HEAD -> treecko) Add treecko.txt
+* a7c56ea (master) Add dummy.txt
+* cbfe4ef initial commit