1package tinygit23import (4 "context"5 "os"6 "os/exec"7 "strings"8 "testing"9)1011func TestPRDiffUsesLocalCommitsAndReportsMetadata(t *testing.T) {12 g, r, base := browseFixture(t)13 tip := r.Refs["refs/heads/main"]14 got := g.PRDiff(context.Background(), r, base, tip)15 if got.Status != "ok" || got.Base != base || got.Tip != tip || got.MergeBase != base {16 t.Fatalf("result = %+v", got)17 }18 if !strings.Contains(got.Diff, "+// second") || got.Truncated {19 t.Fatalf("diff = %+v", got)20 }21}2223func TestPRDiffDoesNotTurnMissingOrUnrelatedObjectsIntoEmptyDiff(t *testing.T) {24 g, r, base := browseFixture(t)25 tip := r.Refs["refs/heads/main"]26 missing := strings.Repeat("f", 40)27 if got := g.PRDiff(context.Background(), r, base, missing); got.Status != "diff_unavailable" || got.Reason == "" {28 t.Fatalf("missing tip result = %+v", got)29 }30 if got := g.PRDiff(context.Background(), r, missing, r.Refs["refs/heads/main"]); got.Status != "diff_unavailable" || got.Reason == "" {31 t.Fatalf("missing base result = %+v", got)32 }33 // The first commit in the fixture is not related to an independently34 // created root. The backend must disclose that it cannot establish a PR35 // base instead of presenting a whole-tree comparison as a normal diff.36 tree, err := exec.Command("git", "--git-dir", g.repoPath(r), "mktree").Output()37 if err != nil {38 t.Fatal(err)39 }40 cmd := exec.Command("git", "--git-dir", g.repoPath(r), "commit-tree", strings.TrimSpace(string(tree)), "-m", "unrelated")41 cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=Test", "GIT_AUTHOR_EMAIL=test@example.test", "GIT_COMMITTER_NAME=Test", "GIT_COMMITTER_EMAIL=test@example.test")42 otherBytes, err := cmd.Output()43 if err != nil {44 t.Fatal(err)45 }46 other := strings.TrimSpace(string(otherBytes))47 if got := g.PRDiff(context.Background(), r, other, base); got.Status != "diff_unavailable" {48 t.Fatalf("unrelated result = %+v", got)49 }50 // This base is an ancestor of the PR tip but belongs only to that PR;51 // it is not an ancestor of the repository target.52 treeBytes, err := exec.Command("git", "--git-dir", g.repoPath(r), "rev-parse", base+"^{tree}").Output()53 if err != nil {54 t.Fatal(err)55 }56 commit := func(parents ...string) string {57 args := []string{"--git-dir", g.repoPath(r), "commit-tree", strings.TrimSpace(string(treeBytes))}58 for _, parent := range parents {59 args = append(args, "-p", parent)60 }61 args = append(args, "-m", "PR-only")62 cmd := exec.Command("git", args...)63 cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=Test", "GIT_AUTHOR_EMAIL=test@example.test", "GIT_COMMITTER_NAME=Test", "GIT_COMMITTER_EMAIL=test@example.test")64 out, err := cmd.Output()65 if err != nil {66 t.Fatal(err)67 }68 return strings.TrimSpace(string(out))69 }70 prBase := commit(base)71 prTip := commit(prBase)72 if got := g.PRDiff(context.Background(), r, prBase, prTip); got.Status != "diff_unavailable" {73 t.Fatalf("PR-only ancestor result = %+v (main tip %s)", got, tip)74 }75}7677func TestPRDiffAcceptsBaseWhenTargetBranchDiverged(t *testing.T) {78 g, r, base := browseFixture(t)79 tip := r.Refs["refs/heads/main"]80 treeBytes, err := exec.Command("git", "--git-dir", g.repoPath(r), "rev-parse", base+"^{tree}").Output()81 if err != nil {82 t.Fatal(err)83 }84 commit := func(message string) string {85 cmd := exec.Command("git", "--git-dir", g.repoPath(r), "commit-tree", strings.TrimSpace(string(treeBytes)), "-p", base, "-m", message)86 cmd.Env = append(os.Environ(), "GIT_AUTHOR_NAME=Test", "GIT_AUTHOR_EMAIL=test@example.test", "GIT_COMMITTER_NAME=Test", "GIT_COMMITTER_EMAIL=test@example.test")87 out, err := cmd.Output()88 if err != nil {89 t.Fatal(err)90 }91 return strings.TrimSpace(string(out))92 }93 target := commit("target branch")94 if err := exec.Command("git", "--git-dir", g.repoPath(r), "update-ref", "refs/heads/target", target).Run(); err != nil {95 t.Fatal(err)96 }97 r.Head = "refs/heads/target"98 got := g.PRDiff(context.Background(), r, base, tip)99 if got.Status != "ok" || got.MergeBase != base {100 t.Fatalf("diverged target result = %+v", got)101 }102}103104func TestPRDiffFindsMergeBaseFromRepositoryHead(t *testing.T) {105 g, r, base := browseFixture(t)106 tip := r.Refs["refs/heads/main"]107 r.Head = "refs/heads/main"108 got := g.PRDiff(context.Background(), r, "", tip)109 if got.Status != "ok" || got.MergeBase != tip || got.Base != tip {110 t.Fatalf("result = %+v (base fixture commit %s)", got, base)111 }112}