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