Fix error when KeyValuePair file is empty or does not exist - Fixes #34

[PlagueHO]

Pull Request (PR) description

This PR fixes an error that occurs when the KeyValuePair file is empty or does not exist.

It also cleans up the unit tests to make them less fragile.

This Pull Request (PR) fixes the following issues

• Fixes KeyValuePairFile: Unable to insert into empty file. #34

Task list

• Added an entry under the Unreleased section of the change log in the CHANGELOG.md.
  Entry should say what was changed, and how that affects users (if applicable).
• Resource documentation added/updated in README.md in resource folder.
• Resource parameter descriptions added/updated in schema.mof
  and comment-based help.
• Comment-based help added/updated.
• Localization strings added/updated in all localization files as appropriate.
• Examples appropriately added/updated.
• Unit tests added/updated. See DSC Resource Testing Guidelines.
• Integration tests added/updated (where possible). See DSC Resource Testing Guidelines.
• New/changed code adheres to DSC Resource Style Guidelines and Best Practices.

@johlju - would you mind reviewing this when you have a moment? Sorry about the length of the change in the unit tests - I decided to refactor them to make them less brittle.

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This change is 

[codecov]

Codecov Report

Merging #35 into dev will increase coverage by <1%.
The diff coverage is 97%.

@@        Coverage Diff         @@
##           dev   #35    +/-   ##
==================================
+ Coverage   68%   69%   +<1%     
==================================
  Files        4     4            
  Lines      443   452     +9     
==================================
+ Hits       304   314    +10     
+ Misses     139   138     -1

[johlju]

This looks good to me, two non-blocking comments.

Reviewed 5 of 5 files at r1.
Reviewable status: complete! all files reviewed, all discussions resolved

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DSCResources/DSR_KeyValuePairFile/DSR_KeyValuePairFile.psm1, line 44 at r1 (raw file):

$fileEncoding = 'ASCII'

We must return 'ASCII' here because it is a validate set for that property? Returning $nullwill fail? Would have been better to return $null since we don't know the encoding if the file does not exist. But might fail with Get-DscConfiguration or Invoke-DscResource -Method Get. 🤔

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Tests/Unit/DSR_KeyValuePairFile.Tests.ps1, line 148 at r1 (raw file):

                    Assert-MockCalled -CommandName Get-Content `
                        -Exactly -Times 0

Maybe add Scope to all of these? You can add that in another PR if you like.

[PlagueHO]

@johlju - did all the fixes 😁 could you sign off again for me when you have a moment?

Reviewable status: 3 of 5 files reviewed, all discussions resolved (waiting on @johlju)

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DSCResources/DSR_KeyValuePairFile/DSR_KeyValuePairFile.psm1, line 44 at r1 (raw file):

Previously, johlju (Johan Ljunggren) wrote…

$fileEncoding = 'ASCII'

We must return 'ASCII' here because it is a validate set for that property? Returning $nullwill fail? Would have been better to return $null since we don't know the encoding if the file does not exist. But might fail with Get-DscConfiguration or Invoke-DscResource -Method Get. 🤔

Fixed!

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Tests/Unit/DSR_KeyValuePairFile.Tests.ps1, line 148 at r1 (raw file):

Previously, johlju (Johan Ljunggren) wrote…

                    Assert-MockCalled -CommandName Get-Content `
                        -Exactly -Times 0

Maybe add Scope to all of these? You can add that in another PR if you like.

Done

[johlju]

Reviewed 2 of 2 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved