#!/bin/sh

global test_description := ''checkout ''

source ./test-lib.sh

# Arguments: <branch> <sha> [<checkout options>]
#
# Runs "git checkout" to switch to <branch>, testing that
#
#   1) we are on the specified branch, <branch>;
#   2) HEAD is <sha>; if <sha> is not specified, the old HEAD is used.
#
# If <checkout options> is not specified, "git checkout" is run with -b.
proc do_checkout {
	global exp_branch := $1 &&
	global exp_ref := ""refs/heads/$exp_branch"" &&

	# if <sha> is not specified, use HEAD.
	global exp_sha := $(2:-$(git rev-parse --verify HEAD)) &&

	# default options for git checkout: -b
	if test -z $3 {
		global opts := '"-b'"
	} else {
		global opts := $3
	}

	git checkout $opts $exp_branch $exp_sha &&

	test $exp_ref = $[git rev-parse --symbolic-full-name HEAD] &&
	test $exp_sha = $[git rev-parse --verify HEAD]
}

proc test_dirty_unmergeable {
	! git diff --exit-code >/dev/null
}

proc setup_dirty_unmergeable {
	echo >>file1 change2>>file1 change2
}

proc test_dirty_mergeable {
	! git diff --cached --exit-code >/dev/null
}

proc setup_dirty_mergeable {
	echo >file2 file2>file2 file2 &&
	git add file2
}

test_expect_success 'setup' '
	test_commit initial file1 &&
	HEAD1=$(git rev-parse --verify HEAD) &&

	test_commit change1 file1 &&
	HEAD2=$(git rev-parse --verify HEAD) &&

	git branch -m branch1
'

test_expect_success 'checkout -b to a new branch, set to HEAD' '
	do_checkout branch2
'

test_expect_success 'checkout -b to a new branch, set to an explicit ref' '
	git checkout branch1 &&
	git branch -D branch2 &&

	do_checkout branch2 $HEAD1
'

test_expect_success 'checkout -b to a new branch with unmergeable changes fails' '
	git checkout branch1 &&

	# clean up from previous test
	git branch -D branch2 &&

	setup_dirty_unmergeable &&
	test_must_fail do_checkout branch2 $HEAD1 &&
	test_dirty_unmergeable
'

test_expect_success 'checkout -f -b to a new branch with unmergeable changes discards changes' '
	# still dirty and on branch1
	do_checkout branch2 $HEAD1 "-f -b" &&
	test_must_fail test_dirty_unmergeable
'

test_expect_success 'checkout -b to a new branch preserves mergeable changes' '
	git checkout branch1 &&

	# clean up from previous test
	git branch -D branch2 &&

	setup_dirty_mergeable &&
	do_checkout branch2 $HEAD1 &&
	test_dirty_mergeable
'

test_expect_success 'checkout -f -b to a new branch with mergeable changes discards changes' '
	# clean up from previous test
	git reset --hard &&

	git checkout branch1 &&

	# clean up from previous test
	git branch -D branch2 &&

	setup_dirty_mergeable &&
	do_checkout branch2 $HEAD1 "-f -b" &&
	test_must_fail test_dirty_mergeable
'

test_expect_success 'checkout -b to an existing branch fails' '
	git reset --hard HEAD &&

	test_must_fail do_checkout branch2 $HEAD2
'

test_expect_success 'checkout -b to @{-1} fails with the right branch name' '
	git reset --hard HEAD &&
	git checkout branch1 &&
	git checkout branch2 &&
	echo  >expect "fatal: A branch named '''''branch1''''' already exists." &&
	test_must_fail git checkout -b @{-1} 2>actual &&
	test_i18ncmp expect actual
'

test_expect_success 'checkout -B to an existing branch resets branch to HEAD' '
	git checkout branch1 &&

	do_checkout branch2 "" -B
'

test_expect_success 'checkout -B to an existing branch from detached HEAD resets branch to HEAD' '
	git checkout $(git rev-parse --verify HEAD) &&

	do_checkout branch2 "" -B
'

test_expect_success 'checkout -B to an existing branch with an explicit ref resets branch to that ref' '
	git checkout branch1 &&

	do_checkout branch2 $HEAD1 -B
'

test_expect_success 'checkout -B to an existing branch with unmergeable changes fails' '
	git checkout branch1 &&

	setup_dirty_unmergeable &&
	test_must_fail do_checkout branch2 $HEAD1 -B &&
	test_dirty_unmergeable
'

test_expect_success 'checkout -f -B to an existing branch with unmergeable changes discards changes' '
	# still dirty and on branch1
	do_checkout branch2 $HEAD1 "-f -B" &&
	test_must_fail test_dirty_unmergeable
'

test_expect_success 'checkout -B to an existing branch preserves mergeable changes' '
	git checkout branch1 &&

	setup_dirty_mergeable &&
	do_checkout branch2 $HEAD1 -B &&
	test_dirty_mergeable
'

test_expect_success 'checkout -f -B to an existing branch with mergeable changes discards changes' '
	# clean up from previous test
	git reset --hard &&

	git checkout branch1 &&

	setup_dirty_mergeable &&
	do_checkout branch2 $HEAD1 "-f -B" &&
	test_must_fail test_dirty_mergeable
'

test_expect_success 'checkout -b <describe>' '
	git tag -f -m "First commit" initial initial &&
	git checkout -f change1 &&
	name=$(git describe) &&
	git checkout -b $name &&
	git diff --exit-code change1 &&
	echo "refs/heads/$name" >expect &&
	git symbolic-ref HEAD >actual &&
	test_cmp expect actual
'

test_expect_success 'checkout -B to the current branch works' '
	git checkout branch1 &&
	git checkout -B branch1-scratch &&

	setup_dirty_mergeable &&
	git checkout -B branch1-scratch initial &&
	test_dirty_mergeable
'

test_done
(CommandList
  children: [
    (Assignment
      keyword: Assign_None
      pairs: [
        (assign_pair
          lhs: (LhsName name:test_description)
          op: Equal
          rhs: {(SQ <"checkout ">)}
          spids: [4]
        )
      ]
      spids: [4]
    )
    (C {(.)} {(./test-lib.sh)})
    (FuncDef
      name: do_checkout
      body: 
        (BraceGroup
          children: [
            (AndOr
              children: [
                (Assignment
                  keyword: Assign_None
                  pairs: [
                    (assign_pair
                      lhs: (LhsName name:exp_branch)
                      op: Equal
                      rhs: {($ VSub_Number "$1")}
                      spids: [46]
                    )
                  ]
                  spids: [46]
                )
                (AndOr
                  children: [
                    (Assignment
                      keyword: Assign_None
                      pairs: [
                        (assign_pair
                          lhs: (LhsName name:exp_ref)
                          op: Equal
                          rhs: {(DQ (refs/heads/) ($ VSub_Name "$exp_branch"))}
                          spids: [52]
                        )
                      ]
                      spids: [52]
                    )
                    (AndOr
                      children: [
                        (Assignment
                          keyword: Assign_None
                          pairs: [
                            (assign_pair
                              lhs: (LhsName name:exp_sha)
                              op: Equal
                              rhs: 
                                {
                                  (BracedVarSub
                                    token: <VSub_Number 2>
                                    suffix_op: 
                                      (StringUnary
                                        op_id: VTest_ColonHyphen
                                        arg_word: 
                                          {
                                            (CommandSubPart
                                              command_list: 
                                                (CommandList
                                                  children: [
                                                    (C {(git)} {(rev-parse)} {(--verify)} {(HEAD)})
                                                  ]
                                                )
                                              left_token: <Left_CommandSub "$(">
                                              spids: [70 78]
                                            )
                                          }
                                      )
                                    spids: [67 79]
                                  )
                                }
                              spids: [66]
                            )
                          ]
                          spids: [66]
                        )
                        (If
                          arms: [
                            (if_arm
                              cond: [
                                (Sentence
                                  child: 
                                    (C {(Lit_Other "[")} {(-z)} {(DQ ($ VSub_Number "$3"))} 
                                      {(Lit_Other "]")}
                                    )
                                  terminator: <Op_Semi ";">
                                )
                              ]
                              action: [
                                (Assignment
                                  keyword: Assign_None
                                  pairs: [
                                    (assign_pair
                                      lhs: (LhsName name:opts)
                                      op: Equal
                                      rhs: {(DQ (-b))}
                                      spids: [105]
                                    )
                                  ]
                                  spids: [105]
                                )
                              ]
                              spids: [-1 102]
                            )
                          ]
                          else_action: [
                            (Assignment
                              keyword: Assign_None
                              pairs: [
                                (assign_pair
                                  lhs: (LhsName name:opts)
                                  op: Equal
                                  rhs: {(DQ ($ VSub_Number "$3"))}
                                  spids: [114]
                                )
                              ]
                              spids: [114]
                            )
                          ]
                          spids: [111 120]
                        )
                      ]
                      op_id: Op_DAmp
                    )
                  ]
                  op_id: Op_DAmp
                )
              ]
              op_id: Op_DAmp
            )
            (AndOr
              children: [
                (C {(git)} {(checkout)} {($ VSub_Name "$opts")} {($ VSub_Name "$exp_branch")} 
                  {($ VSub_Name "$exp_sha")}
                )
                (AndOr
                  children: [
                    (C {(test)} {($ VSub_Name "$exp_ref")} {(Lit_Other "=")} 
                      {
                        (CommandSubPart
                          command_list: 
                            (CommandList
                              children: [(C {(git)} {(rev-parse)} {(--symbolic-full-name)} {(HEAD)})]
                            )
                          left_token: <Left_CommandSub "$(">
                          spids: [144 152]
                        )
                      }
                    )
                    (C {(test)} {($ VSub_Name "$exp_sha")} {(Lit_Other "=")} 
                      {
                        (CommandSubPart
                          command_list: 
                            (CommandList
                              children: [(C {(git)} {(rev-parse)} {(--verify)} {(HEAD)})]
                            )
                          left_token: <Left_CommandSub "$(">
                          spids: [163 171]
                        )
                      }
                    )
                  ]
                  op_id: Op_DAmp
                )
              ]
              op_id: Op_DAmp
            )
          ]
          spids: [43]
        )
      spids: [39 42]
    )
    (FuncDef
      name: test_dirty_unmergeable
      body: 
        (BraceGroup
          children: [
            (Pipeline
              children: [
                (SimpleCommand
                  words: [{(git)} {(diff)} {(--exit-code)}]
                  redirects: [(Redir op_id:Redir_Great fd:-1 arg_word:{(/dev/null)} spids:[191])]
                )
              ]
              negated: True
            )
          ]
          spids: [180]
        )
      spids: [176 179]
    )
    (FuncDef
      name: setup_dirty_unmergeable
      body: 
        (BraceGroup
          children: [
            (SimpleCommand
              words: [{(echo)} {(change2)}]
              redirects: [(Redir op_id:Redir_DGreat fd:-1 arg_word:{(file1)} spids:[206])]
            )
          ]
          spids: [201]
        )
      spids: [197 200]
    )
    (FuncDef
      name: test_dirty_mergeable
      body: 
        (BraceGroup
          children: [
            (Pipeline
              children: [
                (SimpleCommand
                  words: [{(git)} {(diff)} {(--cached)} {(--exit-code)}]
                  redirects: [(Redir op_id:Redir_Great fd:-1 arg_word:{(/dev/null)} spids:[231])]
                )
              ]
              negated: True
            )
          ]
          spids: [218]
        )
      spids: [214 217]
    )
    (FuncDef
      name: setup_dirty_mergeable
      body: 
        (BraceGroup
          children: [
            (AndOr
              children: [
                (SimpleCommand
                  words: [{(echo)} {(file2)}]
                  redirects: [(Redir op_id:Redir_Great fd:-1 arg_word:{(file2)} spids:[246])]
                )
                (C {(git)} {(add)} {(file2)})
              ]
              op_id: Op_DAmp
            )
          ]
          spids: [241]
        )
      spids: [237 240]
    )
    (C {(test_expect_success)} {(SQ <setup>)} 
      {
        (SQ <"\n"> <"\ttest_commit initial file1 &&\n"> <"\tHEAD1=$(git rev-parse --verify HEAD) &&\n"> 
          <"\n"> <"\ttest_commit change1 file1 &&\n"> <"\tHEAD2=$(git rev-parse --verify HEAD) &&\n"> <"\n"> 
          <"\tgit branch -m branch1\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to a new branch, set to HEAD">)} 
      {(SQ <"\n"> <"\tdo_checkout branch2\n">)}
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to a new branch, set to an explicit ref">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\tgit branch -D branch2 &&\n"> <"\n"> 
          <"\tdo_checkout branch2 $HEAD1\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to a new branch with unmergeable changes fails">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\t# clean up from previous test\n"> 
          <"\tgit branch -D branch2 &&\n"> <"\n"> <"\tsetup_dirty_unmergeable &&\n"> <"\ttest_must_fail do_checkout branch2 $HEAD1 &&\n"> 
          <"\ttest_dirty_unmergeable\n">
        )
      }
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -f -b to a new branch with unmergeable changes discards changes">)} 
      {
        (SQ <"\n"> <"\t# still dirty and on branch1\n"> <"\tdo_checkout branch2 $HEAD1 \"-f -b\" &&\n"> 
          <"\ttest_must_fail test_dirty_unmergeable\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to a new branch preserves mergeable changes">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\t# clean up from previous test\n"> 
          <"\tgit branch -D branch2 &&\n"> <"\n"> <"\tsetup_dirty_mergeable &&\n"> <"\tdo_checkout branch2 $HEAD1 &&\n"> 
          <"\ttest_dirty_mergeable\n">
        )
      }
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -f -b to a new branch with mergeable changes discards changes">)} 
      {
        (SQ <"\n"> <"\t# clean up from previous test\n"> <"\tgit reset --hard &&\n"> <"\n"> 
          <"\tgit checkout branch1 &&\n"> <"\n"> <"\t# clean up from previous test\n"> <"\tgit branch -D branch2 &&\n"> <"\n"> 
          <"\tsetup_dirty_mergeable &&\n"> <"\tdo_checkout branch2 $HEAD1 \"-f -b\" &&\n"> <"\ttest_must_fail test_dirty_mergeable\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to an existing branch fails">)} 
      {
        (SQ <"\n"> <"\tgit reset --hard HEAD &&\n"> <"\n"> 
          <"\ttest_must_fail do_checkout branch2 $HEAD2\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b to @{-1} fails with the right branch name">)} 
      {
        (SQ <"\n"> <"\tgit reset --hard HEAD &&\n"> <"\tgit checkout branch1 &&\n"> 
          <"\tgit checkout branch2 &&\n"> <"\techo  >expect \"fatal: A branch named ">
        ) (EscapedLiteralPart token:<Lit_EscapedChar "\\'">) (SQ <branch1>) 
        (EscapedLiteralPart token:<Lit_EscapedChar "\\'">) 
        (SQ <" already exists.\" &&\n"> <"\ttest_must_fail git checkout -b @{-1} 2>actual &&\n"> 
          <"\ttest_i18ncmp expect actual\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -B to an existing branch resets branch to HEAD">)} 
      {(SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\tdo_checkout branch2 \"\" -B\n">)}
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -B to an existing branch from detached HEAD resets branch to HEAD">)} 
      {
        (SQ <"\n"> <"\tgit checkout $(git rev-parse --verify HEAD) &&\n"> <"\n"> 
          <"\tdo_checkout branch2 \"\" -B\n">
        )
      }
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -B to an existing branch with an explicit ref resets branch to that ref">)} {(SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\tdo_checkout branch2 $HEAD1 -B\n">)}
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -B to an existing branch with unmergeable changes fails">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\tsetup_dirty_unmergeable &&\n"> 
          <"\ttest_must_fail do_checkout branch2 $HEAD1 -B &&\n"> <"\ttest_dirty_unmergeable\n">
        )
      }
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -f -B to an existing branch with unmergeable changes discards changes">)} 
      {
        (SQ <"\n"> <"\t# still dirty and on branch1\n"> <"\tdo_checkout branch2 $HEAD1 \"-f -B\" &&\n"> 
          <"\ttest_must_fail test_dirty_unmergeable\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -B to an existing branch preserves mergeable changes">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\n"> <"\tsetup_dirty_mergeable &&\n"> 
          <"\tdo_checkout branch2 $HEAD1 -B &&\n"> <"\ttest_dirty_mergeable\n">
        )
      }
    )
    (C {(test_expect_success)} 
      {(SQ <"checkout -f -B to an existing branch with mergeable changes discards changes">)} 
      {
        (SQ <"\n"> <"\t# clean up from previous test\n"> <"\tgit reset --hard &&\n"> <"\n"> 
          <"\tgit checkout branch1 &&\n"> <"\n"> <"\tsetup_dirty_mergeable &&\n"> <"\tdo_checkout branch2 $HEAD1 \"-f -B\" &&\n"> 
          <"\ttest_must_fail test_dirty_mergeable\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -b <describe>">)} 
      {
        (SQ <"\n"> <"\tgit tag -f -m \"First commit\" initial initial &&\n"> 
          <"\tgit checkout -f change1 &&\n"> <"\tname=$(git describe) &&\n"> <"\tgit checkout -b $name &&\n"> 
          <"\tgit diff --exit-code change1 &&\n"> <"\techo \"refs/heads/$name\" >expect &&\n"> <"\tgit symbolic-ref HEAD >actual &&\n"> 
          <"\ttest_cmp expect actual\n">
        )
      }
    )
    (C {(test_expect_success)} {(SQ <"checkout -B to the current branch works">)} 
      {
        (SQ <"\n"> <"\tgit checkout branch1 &&\n"> <"\tgit checkout -B branch1-scratch &&\n"> <"\n"> 
          <"\tsetup_dirty_mergeable &&\n"> <"\tgit checkout -B branch1-scratch initial &&\n"> <"\ttest_dirty_mergeable\n">
        )
      }
    )
    (C {(test_done)})
  ]
)