[WIP] Scripts: Add smarter merge conflicts logic

Signed-off-by: timflannagan <[email protected]>

Author: timflannagan

scripts/common.sh

@@ -1,4 +1,5 @@
 #! /bin/bash
 
 export KNOWN_GENERATED_PATHS=(':!vendor' ':!pkg/manifests' ':!manifests' ':!go.sum' ':!go.mod')
+export ROOT_GENERATED_PATHS=( "vendor" "pkg/manifests" "manifests" "go.mod" "go.sum" )
 export UPSTREAM_REMOTES=("api" "operator-registry" "operator-lifecycle-manager")

scripts/sync.sh

@@ -29,7 +29,7 @@ fetch_remote() {
 
 new_candidate_branch() {
     echo "Creating a sync branch if it doesn't already exist"
-    git checkout -b "$SYNC_BRANCH_NAME" upstream/master 2>/dev/null || git checkout "$SYNC_BRANCH_NAME"
+    git checkout -b "$SYNC_BRANCH_NAME" 2>/dev/null || git checkout "$SYNC_BRANCH_NAME"
 }
 
 candidates() {

scripts/sync_pop_candidate.sh

@@ -1,7 +1,5 @@
 #!/usr/bin/env bash
 
-cph=$(git rev-list -n 1 CHERRY_PICK_HEAD 2> /dev/null)
-
 set -o errexit
 set -o pipefail
 
@@ -36,20 +34,44 @@ function pop() {
     fi
     printf 'popping: %s\n' "${rc}"
 
-    if [[ ! $cph ]]; then
-        git cherry-pick --allow-empty --keep-redundant-commits -Xsubtree="${subtree_dir}" "${rc}"
-    else
-        if [[ $cph != "${rc}" ]]; then
-            printf 'unexpected CHERRY_PICK_HEAD:\ngot %s\nexpected: %s\n' "${cph}" "${rc}"
-            exit
-        fi
-        printf 'cherry-pick in progress for %s\n' "${cph}"
-        git add .
+    # Note: this may require a more up-to-date git version
+    if ! git cherry-pick --allow-empty --keep-redundant-commits -Xsubtree="${subtree_dir}" "${rc}"; then
+        # Always blast away the vendor directory given OLM/registry still commit it into source control.
+        git rm -rf "${subtree_dir}"/vendor 2>/dev/null || true
+
+        # TODO: handle the case where there's a single merge conflict.
+        # TODO: handle root go.mod merge conflicts!
+        # TODO: maybe use a while loop here?
+        # TODO: verify there's no remaining merge conflicts
+        num_conflicts=$(git diff --name-only --diff-filter=U --relative | wc -l)
+        while [[ $num_conflicts != 0 ]] ; do
+            file=$(git diff --name-only --diff-filter=U --relative)
+
+            if [[ $file == *"go.mod"* ]]; then
+                git diff "${subtree_dir}"/go.mod
+
+                git checkout --theirs "${subtree_dir}"/go.mod
+                pushd "${subtree_dir}"
+                # Note: handle case where this fails. does this update the root module too?
+                go mod tidy
+                # TODO: double-check there's no remaining markers via git diff --check: <https://stackoverflow.com/questions/3065650/whats-the-simplest-way-to-list-conflicted-files-in-git>?
+                git add go.mod go.sum
+                popd
+            else
+                git checkout --theirs "$file"
+                git diff "$file"
+                git add "$file"
+            fi
+
+            num_conflicts=$(git diff --name-only --diff-filter=U --relative | wc -l)
+            echo "number of merge conflicts remaining: $num_conflicts"
+        done
 
         if [[ -z $(git status --porcelain) ]]; then
             git commit --allow-empty
         else
-            git cherry-pick --continue
+            echo "Current cherry pick status: $(git status --porcelain)"
+            git -c core.editor=true cherry-pick --continue
         fi
     fi
 
@@ -59,8 +81,9 @@ function pop() {
     # 3. Ammend commit
     # 4. Remove from cherrypick set
     make vendor
+    # TODO: make this check smarter and avoid manifest generation when it's not needed.
     make manifests
-    git add "${subtree_dir}" "${KNOWN_GENERATED_PATHS[@]}"
+    git add "${subtree_dir}" "${ROOT_GENERATED_PATHS[@]}"
     git status
     git commit --amend --allow-empty --no-edit --trailer "Upstream-repository: ${remote}" --trailer "Upstream-commit: ${rc}"
 
@@ -72,9 +95,19 @@ function pop() {
     (( --remaining )) || true
     printf '%d picks remaining (pop_all=%s)\n' "${remaining}" "${pop_all}"
 
+    # no changes added to commit (use "git add" and/or "git commit -a")
+    # [sync-2022-08-09 11f50a83b] add grokspawn to OWNERS (#2833)
+    #  Author: grokspawn <[email protected]>
+    #  Date: Tue Aug 9 13:44:11 2022 -0500
+    #  1 file changed, 4 insertions(+), 2 deletions(-)
+    # 0 picks remaining (pop_all=true)
+    # ./scripts/../scripts/sync_pop_candidate.sh: line 108: unexpected EOF while looking for matching `''
+    # make: *** [Makefile:191: sync] Error 2
+    echo "Checking whether there's any remaining cherry picks"
     if [[ $pop_all == 'true' ]] && ((  remaining >  0 )); then
         pop
     fi
+    echo "Done"
 }
 
 pop