Always set the merge base used to merge the commit (#15352) (#15385)

Backport #15352

The issue is that the TestPatch will reset the PR MergeBase - and it is possible for TestPatch to update the MergeBase whilst a merge is ongoing. The ensuing merge will then complete but it doesn't re-set the MergeBase it used to merge the PR.

Fixes the intermittent error in git test.

Signed-off-by: Andrew Thornton art27@cantab.net

integrations/api_helper_for_declarative_test.go

@@ -239,6 +239,26 @@ func doAPICreatePullRequest(ctx APITestContext, owner, repo, baseBranch, headBra
 	}
 }
 
+func doAPIGetPullRequest(ctx APITestContext, owner, repo string, index int64) func(*testing.T) (api.PullRequest, error) {
+	return func(t *testing.T) (api.PullRequest, error) {
+		urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/pulls/%d?token=%s",
+			owner, repo, index, ctx.Token)
+		req := NewRequest(t, http.MethodGet, urlStr)
+
+		expected := 200
+		if ctx.ExpectedCode != 0 {
+			expected = ctx.ExpectedCode
+		}
+		resp := ctx.Session.MakeRequest(t, req, expected)
+
+		json := jsoniter.ConfigCompatibleWithStandardLibrary
+		decoder := json.NewDecoder(resp.Body)
+		pr := api.PullRequest{}
+		err := decoder.Decode(&pr)
+		return pr, err
+	}
+}
+
 func doAPIMergePullRequest(ctx APITestContext, owner, repo string, index int64) func(*testing.T) {
 	return func(t *testing.T) {
 		urlStr := fmt.Sprintf("/api/v1/repos/%s/%s/pulls/%d/merge?token=%s",

integrations/git_test.go

@@ -5,6 +5,7 @@
 package integrations
 
 import (
+	"encoding/hex"
 	"fmt"
 	"io/ioutil"
 	"math/rand"
@@ -451,26 +452,34 @@ func doMergeFork(ctx, baseCtx APITestContext, baseBranch, headBranch string) fun
 
 		// Then get the diff string
 		var diffHash string
+		var diffLength int
 		t.Run("GetDiff", func(t *testing.T) {
 			req := NewRequest(t, "GET", fmt.Sprintf("/%s/%s/pulls/%d.diff", url.PathEscape(baseCtx.Username), url.PathEscape(baseCtx.Reponame), pr.Index))
 			resp := ctx.Session.MakeRequestNilResponseHashSumRecorder(t, req, http.StatusOK)
 			diffHash = string(resp.Hash.Sum(nil))
+			diffLength = resp.Length
 		})
 
 		// Now: Merge the PR & make sure that doesn't break the PR page or change its diff
 		t.Run("MergePR", doAPIMergePullRequest(baseCtx, baseCtx.Username, baseCtx.Reponame, pr.Index))
 		t.Run("EnsureCanSeePull", doEnsureCanSeePull(baseCtx, pr))
-		t.Run("EnsureDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash))
+		t.Run("CheckPR", func(t *testing.T) {
+			oldMergeBase := pr.MergeBase
+			pr2, err := doAPIGetPullRequest(baseCtx, baseCtx.Username, baseCtx.Reponame, pr.Index)(t)
+			assert.NoError(t, err)
+			assert.Equal(t, oldMergeBase, pr2.MergeBase)
+		})
+		t.Run("EnsurDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash, diffLength))
 
 		// Then: Delete the head branch & make sure that doesn't break the PR page or change its diff
 		t.Run("DeleteHeadBranch", doBranchDelete(baseCtx, baseCtx.Username, baseCtx.Reponame, headBranch))
 		t.Run("EnsureCanSeePull", doEnsureCanSeePull(baseCtx, pr))
-		t.Run("EnsureDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash))
+		t.Run("EnsureDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash, diffLength))
 
 		// Delete the head repository & make sure that doesn't break the PR page or change its diff
 		t.Run("DeleteHeadRepository", doAPIDeleteRepository(ctx))
 		t.Run("EnsureCanSeePull", doEnsureCanSeePull(baseCtx, pr))
-		t.Run("EnsureDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash))
+		t.Run("EnsureDiffNoChange", doEnsureDiffNoChange(baseCtx, pr, diffHash, diffLength))
 	}
 }
 
@@ -514,14 +523,15 @@ func doEnsureCanSeePull(ctx APITestContext, pr api.PullRequest) func(t *testing.
 	}
 }
 
-func doEnsureDiffNoChange(ctx APITestContext, pr api.PullRequest, diffHash string) func(t *testing.T) {
+func doEnsureDiffNoChange(ctx APITestContext, pr api.PullRequest, diffHash string, diffLength int) func(t *testing.T) {
 	return func(t *testing.T) {
 		req := NewRequest(t, "GET", fmt.Sprintf("/%s/%s/pulls/%d.diff", url.PathEscape(ctx.Username), url.PathEscape(ctx.Reponame), pr.Index))
 		resp := ctx.Session.MakeRequestNilResponseHashSumRecorder(t, req, http.StatusOK)
 		actual := string(resp.Hash.Sum(nil))
+		actualLength := resp.Length
 
 		equal := diffHash == actual
-		assert.True(t, equal, "Unexpected change in the diff string: expected hash: %s but was actually: %s", diffHash, actual)
+		assert.True(t, equal, "Unexpected change in the diff string: expected hash: %s size: %d but was actually: %s size: %d", hex.EncodeToString([]byte(diffHash)), diffLength, hex.EncodeToString([]byte(actual)), actualLength)
 	}
 }
 

models/pull.go

@@ -406,7 +406,8 @@ func (pr *PullRequest) SetMerged() (bool, error) {
 		return false, fmt.Errorf("Issue.changeStatus: %v", err)
 	}
 
-	if _, err := sess.Where("id = ?", pr.ID).Cols("has_merged, status, merged_commit_id, merger_id, merged_unix").Update(pr); err != nil {
+	// We need to save all of the data used to compute this merge as it may have already been changed by TestPatch. FIXME: need to set some state to prevent TestPatch from running whilst we are merging.
+	if _, err := sess.Where("id = ?", pr.ID).Cols("has_merged, status, merge_base, merged_commit_id, merger_id, merged_unix").Update(pr); err != nil {
 		return false, fmt.Errorf("Failed to update pr[%d]: %v", pr.ID, err)
 	}
 

modules/queue/manager.go

@@ -174,6 +174,7 @@ func (m *Manager) FlushAll(baseCtx context.Context, timeout time.Duration) error
 		default:
 		}
 		mqs := m.ManagedQueues()
+		log.Debug("Found %d Managed Queues", len(mqs))
 		wg := sync.WaitGroup{}
 		wg.Add(len(mqs))
 		allEmpty := true
@@ -184,6 +185,7 @@ func (m *Manager) FlushAll(baseCtx context.Context, timeout time.Duration) error
 			}
 			allEmpty = false
 			if flushable, ok := mq.Managed.(Flushable); ok {
+				log.Debug("Flushing (flushable) queue: %s", mq.Name)
 				go func(q *ManagedQueue) {
 					localCtx, localCancel := context.WithCancel(ctx)
 					pid := q.RegisterWorkers(1, start, hasTimeout, end, localCancel, true)
@@ -196,7 +198,11 @@ func (m *Manager) FlushAll(baseCtx context.Context, timeout time.Duration) error
 					wg.Done()
 				}(mq)
 			} else {
+				log.Debug("Queue: %s is non-empty but is not flushable - adding 100 millisecond wait", mq.Name)
+				go func() {
+					<-time.After(100 * time.Millisecond)
 					wg.Done()
+				}()
 			}
 
 		}

services/pull/merge.go

@@ -64,7 +64,7 @@ func Merge(pr *models.PullRequest, doer *models.User, baseGitRepo *git.Repositor
 	pr.Merger = doer
 	pr.MergerID = doer.ID
 
-	if _, err = pr.SetMerged(); err != nil {
+	if _, err := pr.SetMerged(); err != nil {
 		log.Error("setMerged [%d]: %v", pr.ID, err)
 	}