Fix the wrong push commits in the pull request when force push (#36914)

Fix #36905

The changes focus on force-push PR timeline handling and commit range
calculation:
- Reworked pull-request push comment creation to use a new
`gitrepo.GetCommitIDsBetweenReverse` helper, with special handling for
force pushes (merge-base based range, tolerate missing/invalid old
commits, and keep force-push timeline entries).
- Added `Comment.GetPushActionContent` to parse push comment payloads
and used it to delete only non-force-push push comments during force
pushes.
- Removed the old `Repository.CommitsBetweenNotBase` helper from
`modules/git/repo_commit.go` in favor of the new commit ID range helper.
- Added tests for `GetCommitIDsBetweenReverse` (normal range, `notRef`
filtering, fallback branch usage) and expanded pull comment tests to
cover force-push edge cases.

<img width="989" height="563" alt="image"
src="https://github.com/user-attachments/assets/a01e1bc2-fa8a-4028-8a35-d484e601ff3b"
/>

---------

Signed-off-by: Lunny Xiao <xiaolunwen@gmail.com>
Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/gitrepo/compare.go

@@ -42,3 +42,30 @@ func GetDivergingCommits(ctx context.Context, repo Repository, baseBranch, targe
 	}
 	return &DivergeObject{Ahead: ahead, Behind: behind}, nil
 }
+
+// GetCommitIDsBetweenReverse returns the last commit IDs between two commits in reverse order (from old to new) with limit.
+// If the result exceeds the limit, the old commits IDs will be ignored
+func GetCommitIDsBetweenReverse(ctx context.Context, repo Repository, startRef, endRef, notRef string, limit int) ([]string, error) {
+	genCmd := func(reversions ...string) *gitcmd.Command {
+		cmd := gitcmd.NewCommand("rev-list", "--reverse").
+			AddArguments("-n").AddDynamicArguments(strconv.Itoa(limit)).
+			AddDynamicArguments(reversions...)
+		if notRef != "" { // --not should be kept as the last parameter of git command, otherwise the result will be wrong
+			cmd.AddOptionValues("--not", notRef)
+		}
+		return cmd
+	}
+	stdout, _, err := RunCmdString(ctx, repo, genCmd(startRef+".."+endRef))
+	// example git error message: fatal: origin/main..HEAD: no merge base
+	if err != nil && strings.Contains(err.Stderr(), "no merge base") {
+		// future versions of git >= 2.28 are likely to return an error if before and last have become unrelated.
+		// previously it would return the results of git rev-list before last so let's try that...
+		stdout, _, err = RunCmdString(ctx, repo, genCmd(startRef, endRef))
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	commitIDs := strings.Fields(strings.TrimSpace(stdout))
+	return commitIDs, nil
+}

modules/gitrepo/compare_test.go

@@ -40,3 +40,75 @@ func TestRepoGetDivergingCommits(t *testing.T) {
 		Behind: 2,
 	}, do)
 }
+
+func TestGetCommitIDsBetweenReverse(t *testing.T) {
+	repo := &mockRepository{path: "repo1_bare"}
+
+	// tests raw commit IDs
+	commitIDs, err := GetCommitIDsBetweenReverse(t.Context(), repo,
+		"8d92fc957a4d7cfd98bc375f0b7bb189a0d6c9f2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+		"",
+		100,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{
+		"8006ff9adbf0cb94da7dad9e537e53817f9fa5c0",
+		"6fbd69e9823458e6c4a2fc5c0f6bc022b2f2acd1",
+		"37991dec2c8e592043f47155ce4808d4580f9123",
+		"feaf4ba6bc635fec442f46ddd4512416ec43c2c2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+	}, commitIDs)
+
+	commitIDs, err = GetCommitIDsBetweenReverse(t.Context(), repo,
+		"8d92fc957a4d7cfd98bc375f0b7bb189a0d6c9f2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+		"6fbd69e9823458e6c4a2fc5c0f6bc022b2f2acd1",
+		100,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{
+		"37991dec2c8e592043f47155ce4808d4580f9123",
+		"feaf4ba6bc635fec442f46ddd4512416ec43c2c2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+	}, commitIDs)
+
+	commitIDs, err = GetCommitIDsBetweenReverse(t.Context(), repo,
+		"8d92fc957a4d7cfd98bc375f0b7bb189a0d6c9f2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+		"",
+		3,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{
+		"37991dec2c8e592043f47155ce4808d4580f9123",
+		"feaf4ba6bc635fec442f46ddd4512416ec43c2c2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+	}, commitIDs)
+
+	// test branch names instead of raw commit IDs.
+	commitIDs, err = GetCommitIDsBetweenReverse(t.Context(), repo,
+		"test",
+		"master",
+		"",
+		100,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{
+		"feaf4ba6bc635fec442f46ddd4512416ec43c2c2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+	}, commitIDs)
+
+	// add notref to exclude test
+	commitIDs, err = GetCommitIDsBetweenReverse(t.Context(), repo,
+		"test",
+		"master",
+		"test",
+		100,
+	)
+	assert.NoError(t, err)
+	assert.Equal(t, []string{
+		"feaf4ba6bc635fec442f46ddd4512416ec43c2c2",
+		"ce064814f4a0d337b333e646ece456cd39fab612",
+	}, commitIDs)
+}