Behavioral testing for " describe-doc:fix a obscure error description in the git log documentation"

get_git_log_decorate.Tests.ps1

BeforeAll {
    $PSSR = $PSScriptRoot
    $TestGitRepoName = 'repo'
    function ClearGitRepo {
        Set-Location $PSSR
        if ($TestGitRepoName | Test-Path) {
            Remove-Item $TestGitRepoName -Recurse -Force
        }
    }
    function InitGitRepo {
        Set-Location $PSSR
        git init $TestGitRepoName
        Set-Location $TestGitRepoName
    }
}

Describe 'Some information in Git log cannot be obtained' {
    BeforeAll {
        ClearGitRepo
        InitGitRepo

        $FileName = 'TEST.md'
        '0' | ForEach-Object {
            "line $_">$FileName
            git add $FileName
            git commit -m "r$_ mes"
            git tag "s$_"
        }
    }
    it 'By default, you cannot get the contents in brackets' {
        Out-String -InputObject ((git log) *>&1) | Should -Not -BeLike '*(HEAD -> master, tag: s0)*'
    }
    it "Using auto can't get the content" {
        Out-String -InputObject ((git log --decorate=auto) *>&1) | Should -Not -BeLike '*(HEAD -> master, tag: s0)*'
    }
    It "Explicitly specify '--decorate=short' to get the content in brackets" {
        Out-String -InputObject ((git log --decorate=short) *>&1) | Should -BeLike '*(HEAD -> master, tag: s0)*'
    }
    it 'Use --decorate=full to get more information' {
        Out-String -InputObject ((git log --decorate=full) *>&1) | Should -BeLike '*(HEAD -> refs/heads/master, tag: refs/tags/s0)*'
    }
}