t/t2020-checkout-detach.sh

   1 #!/bin/sh
   2
   3 test_description='checkout into detached HEAD state'
   4 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
   5 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
   6
   7 TEST_PASSES_SANITIZE_LEAK=true
   8 . ./test-lib.sh
   9
  10 check_detached () {
  11         test_must_fail git symbolic-ref -q HEAD >/dev/null
  12 }
  13
  14 check_not_detached () {
  15         git symbolic-ref -q HEAD >/dev/null
  16 }
  17
  18 PREV_HEAD_DESC='Previous HEAD position was'
  19 check_orphan_warning() {
  20         test_grep "you are leaving $2 behind" "$1" &&
  21         test_grep ! "$PREV_HEAD_DESC" "$1"
  22 }
  23 check_no_orphan_warning() {
  24         test_grep ! "you are leaving .* commit.*behind" "$1" &&
  25         test_grep "$PREV_HEAD_DESC" "$1"
  26 }
  27
  28 reset () {
  29         git checkout main &&
  30         check_not_detached
  31 }
  32
  33 test_expect_success 'setup' '
  34         test_commit one &&
  35         test_commit two &&
  36         test_commit three && git tag -d three &&
  37         test_commit four && git tag -d four &&
  38         git branch branch &&
  39         git tag tag
  40 '
  41
  42 test_expect_success 'checkout branch does not detach' '
  43         reset &&
  44         git checkout branch &&
  45         check_not_detached
  46 '
  47
  48 for opt in "HEAD" "@"
  49 do
  50         test_expect_success "checkout $opt no-op/don't detach" '
  51                 reset &&
  52                 cat .git/HEAD >expect &&
  53                 git checkout $opt &&
  54                 cat .git/HEAD >actual &&
  55                 check_not_detached &&
  56                 test_cmp expect actual
  57         '
  58 done
  59
  60 test_expect_success 'checkout tag detaches' '
  61         reset &&
  62         git checkout tag &&
  63         check_detached
  64 '
  65
  66 test_expect_success 'checkout branch by full name detaches' '
  67         reset &&
  68         git checkout refs/heads/branch &&
  69         check_detached
  70 '
  71
  72 test_expect_success 'checkout non-ref detaches' '
  73         reset &&
  74         git checkout branch^ &&
  75         check_detached
  76 '
  77
  78 test_expect_success 'checkout ref^0 detaches' '
  79         reset &&
  80         git checkout branch^0 &&
  81         check_detached
  82 '
  83
  84 test_expect_success 'checkout --detach detaches' '
  85         reset &&
  86         git checkout --detach branch &&
  87         check_detached
  88 '
  89
  90 test_expect_success 'checkout --detach without branch name' '
  91         reset &&
  92         git checkout --detach &&
  93         check_detached
  94 '
  95
  96 test_expect_success 'checkout --detach errors out for non-commit' '
  97         reset &&
  98         test_must_fail git checkout --detach one^{tree} &&
  99         check_not_detached
 100 '
 101
 102 test_expect_success 'checkout --detach errors out for extra argument' '
 103         reset &&
 104         git checkout main &&
 105         test_must_fail git checkout --detach tag one.t &&
 106         check_not_detached
 107 '
 108
 109 test_expect_success 'checkout --detached and -b are incompatible' '
 110         reset &&
 111         test_must_fail git checkout --detach -b newbranch tag &&
 112         check_not_detached
 113 '
 114
 115 test_expect_success 'checkout --detach moves HEAD' '
 116         reset &&
 117         git checkout one &&
 118         git checkout --detach two &&
 119         git diff --exit-code HEAD &&
 120         git diff --exit-code two
 121 '
 122
 123 test_expect_success 'checkout warns on orphan commits' '
 124         reset &&
 125         git checkout --detach two &&
 126         echo content >orphan &&
 127         git add orphan &&
 128         git commit -a -m orphan1 &&
 129         echo new content >orphan &&
 130         git commit -a -m orphan2 &&
 131         orphan2=$(git rev-parse HEAD) &&
 132         git checkout main 2>stderr
 133 '
 134
 135 test_expect_success 'checkout warns on orphan commits: output' '
 136         check_orphan_warning stderr "2 commits"
 137 '
 138
 139 test_expect_success 'checkout warns orphaning 1 of 2 commits' '
 140         git checkout "$orphan2" &&
 141         git checkout HEAD^ 2>stderr
 142 '
 143
 144 test_expect_success 'checkout warns orphaning 1 of 2 commits: output' '
 145         check_orphan_warning stderr "1 commit"
 146 '
 147
 148 test_expect_success 'checkout does not warn leaving ref tip' '
 149         reset &&
 150         git checkout --detach two &&
 151         git checkout main 2>stderr
 152 '
 153
 154 test_expect_success 'checkout does not warn leaving ref tip' '
 155         check_no_orphan_warning stderr
 156 '
 157
 158 test_expect_success 'checkout does not warn leaving reachable commit' '
 159         reset &&
 160         git checkout --detach HEAD^ &&
 161         git checkout main 2>stderr
 162 '
 163
 164 test_expect_success 'checkout does not warn leaving reachable commit' '
 165         check_no_orphan_warning stderr
 166 '
 167
 168 cat >expect <<'EOF'
 169 Your branch is behind 'main' by 1 commit, and can be fast-forwarded.
 170   (use "git pull" to update your local branch)
 171 EOF
 172 test_expect_success 'tracking count is accurate after orphan check' '
 173         reset &&
 174         git branch child main^ &&
 175         git config branch.child.remote . &&
 176         git config branch.child.merge refs/heads/main &&
 177         git checkout child^ &&
 178         git checkout child >stdout &&
 179         test_cmp expect stdout &&
 180
 181         git checkout --detach child >stdout &&
 182         test_grep ! "can be fast-forwarded\." stdout
 183 '
 184
 185 test_expect_success 'no advice given for explicit detached head state' '
 186         # baseline
 187         test_config advice.detachedHead true &&
 188         git checkout child && git checkout HEAD^0 >expect.advice 2>&1 &&
 189         test_config advice.detachedHead false &&
 190         git checkout child && git checkout HEAD^0 >expect.no-advice 2>&1 &&
 191         test_unconfig advice.detachedHead &&
 192         # without configuration, the advice.* variables default to true
 193         git checkout child && git checkout HEAD^0 >actual 2>&1 &&
 194         test_cmp expect.advice actual &&
 195
 196         # with explicit --detach
 197         # no configuration
 198         test_unconfig advice.detachedHead &&
 199         git checkout child && git checkout --detach HEAD^0 >actual 2>&1 &&
 200         test_cmp expect.no-advice actual &&
 201
 202         # explicitly decline advice
 203         test_config advice.detachedHead false &&
 204         git checkout child && git checkout --detach HEAD^0 >actual 2>&1 &&
 205         test_cmp expect.no-advice actual
 206 '
 207
 208 # Detached HEAD tests for GIT_PRINT_SHA1_ELLIPSIS (new format)
 209 test_expect_success 'describe_detached_head prints no SHA-1 ellipsis when not asked to' "
 210
 211         commit=$(git rev-parse --short=12 main^) &&
 212         commit2=$(git rev-parse --short=12 main~2) &&
 213         commit3=$(git rev-parse --short=12 main~3) &&
 214
 215         # The first detach operation is more chatty than the following ones.
 216         cat >1st_detach <<-EOF &&
 217         Note: switching to 'HEAD^'.
 218
 219         You are in 'detached HEAD' state. You can look around, make experimental
 220         changes and commit them, and you can discard any commits you make in this
 221         state without impacting any branches by switching back to a branch.
 222
 223         If you want to create a new branch to retain commits you create, you may
 224         do so (now or later) by using -c with the switch command. Example:
 225
 226           git switch -c <new-branch-name>
 227
 228         Or undo this operation with:
 229
 230           git switch -
 231
 232         Turn off this advice by setting config variable advice.detachedHead to false
 233
 234         HEAD is now at \$commit three
 235         EOF
 236
 237         # The remaining ones just show info about previous and current HEADs.
 238         cat >2nd_detach <<-EOF &&
 239         Previous HEAD position was \$commit three
 240         HEAD is now at \$commit2 two
 241         EOF
 242
 243         cat >3rd_detach <<-EOF &&
 244         Previous HEAD position was \$commit2 two
 245         HEAD is now at \$commit3 one
 246         EOF
 247
 248         reset &&
 249         check_not_detached &&
 250
 251         # Various ways of *not* asking for ellipses
 252
 253         sane_unset GIT_PRINT_SHA1_ELLIPSIS &&
 254         git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 255         check_detached &&
 256         test_cmp 1st_detach actual &&
 257
 258         GIT_PRINT_SHA1_ELLIPSIS="no" git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 259         check_detached &&
 260         test_cmp 2nd_detach actual &&
 261
 262         GIT_PRINT_SHA1_ELLIPSIS= git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 263         check_detached &&
 264         test_cmp 3rd_detach actual &&
 265
 266         sane_unset GIT_PRINT_SHA1_ELLIPSIS &&
 267
 268         # We only have four commits, but we can re-use them
 269         reset &&
 270         check_not_detached &&
 271
 272         # Make no mention of the env var at all
 273         git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 274         check_detached &&
 275         test_cmp 1st_detach actual &&
 276
 277         GIT_PRINT_SHA1_ELLIPSIS='nope' &&
 278         git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 279         check_detached &&
 280         test_cmp 2nd_detach actual &&
 281
 282         GIT_PRINT_SHA1_ELLIPSIS=nein &&
 283         git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 284         check_detached &&
 285         test_cmp 3rd_detach actual &&
 286
 287         true
 288 "
 289
 290 # Detached HEAD tests for GIT_PRINT_SHA1_ELLIPSIS (old format)
 291 test_expect_success 'describe_detached_head does print SHA-1 ellipsis when asked to' "
 292
 293         commit=$(git rev-parse --short=12 main^) &&
 294         commit2=$(git rev-parse --short=12 main~2) &&
 295         commit3=$(git rev-parse --short=12 main~3) &&
 296
 297         # The first detach operation is more chatty than the following ones.
 298         cat >1st_detach <<-EOF &&
 299         Note: switching to 'HEAD^'.
 300
 301         You are in 'detached HEAD' state. You can look around, make experimental
 302         changes and commit them, and you can discard any commits you make in this
 303         state without impacting any branches by switching back to a branch.
 304
 305         If you want to create a new branch to retain commits you create, you may
 306         do so (now or later) by using -c with the switch command. Example:
 307
 308           git switch -c <new-branch-name>
 309
 310         Or undo this operation with:
 311
 312           git switch -
 313
 314         Turn off this advice by setting config variable advice.detachedHead to false
 315
 316         HEAD is now at \$commit... three
 317         EOF
 318
 319         # The remaining ones just show info about previous and current HEADs.
 320         cat >2nd_detach <<-EOF &&
 321         Previous HEAD position was \$commit... three
 322         HEAD is now at \$commit2... two
 323         EOF
 324
 325         cat >3rd_detach <<-EOF &&
 326         Previous HEAD position was \$commit2... two
 327         HEAD is now at \$commit3... one
 328         EOF
 329
 330         reset &&
 331         check_not_detached &&
 332
 333         # Various ways of asking for ellipses...
 334         # The user can just use any kind of quoting (including none).
 335
 336         GIT_PRINT_SHA1_ELLIPSIS=yes git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 337         check_detached &&
 338         test_cmp 1st_detach actual &&
 339
 340         GIT_PRINT_SHA1_ELLIPSIS=Yes git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 341         check_detached &&
 342         test_cmp 2nd_detach actual &&
 343
 344         GIT_PRINT_SHA1_ELLIPSIS=YES git -c 'core.abbrev=12' checkout HEAD^ >actual 2>&1 &&
 345         check_detached &&
 346         test_cmp 3rd_detach actual &&
 347
 348         true
 349 "
 350
 351 test_done