covet

README

covet

Cover it!

covet reads version control diffs and Go coverage files to generate useful stats about their intersection. Currently displays coverage percentage of the diff and highlights any new, uncovered lines.

go install github.com/johnstarich/go/covet/cmd/covet@latest
covet -help

git diff HEAD~10...HEAD > my.diff
go test -coverprofile=cover.out ./...

covet -diff-file my.diff -cover-go cover.out
#  ... includes diff and coverage intersection ...
# Total diff coverage:  84.1%
#
# Diff coverage is below target. Add tests for these files:
#
# ┌─────────┬──────────────┬────────────────────────────────────────────┐
# │ LINES   │ COVERAGE     │ FILE                                       │
# ├─────────┼──────────────┼────────────────────────────────────────────┤
# │ 239/279 │  85.7% ████▎ │ diffcover/cmd/diffcover/run.go             │
# │  16/42  │  38.1% █▉    │ diffcover/cmd/diffcover/coverage_status.go │
# └─────────┴──────────────┴────────────────────────────────────────────┘

Still experimental: Future releases may contain breaking changes.

Thoughts or questions? Please open an issue to discuss.

Integrate with GitHub

Covet includes an automatic GitHub Actions integration and opt-in GitHub comment summary reports.

To enable comment summaries, you need to set a few additional flags.

Here's an example using GitHub Actions:

  test:
    runs-on: ubuntu-latest
    permissions:
      pull-requests: write
    steps:
    - uses: actions/checkout@v3
    - name: checkout
      run: |
        commits=${{ github.event.pull_request.commits }}
        if [[ -n "$commits" ]]; then
          # Prepare enough depth for diffs with master
          git fetch --depth="$(( commits + 1 ))"
        fi
    - uses: actions/setup-go@v3
      with:
        go-version: 1.16.x
    - name: Test
      run: |
        git diff origin/master | \
            covet \
                -diff-file - \
                -cover-go ./cover.out \
                -show-diff-coverage \
                -gh-token "$GITHUB_TOKEN" \
                -gh-issue "github.com/${GITHUB_REPOSITORY}/pull/${ISSUE_NUMBER}" 
      env:
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

And here's an example using environment variables from Travis CI:

git diff origin/master | \
    covet \
        -diff-file - \
        -cover-go ./cover.out \
        -show-diff-coverage \
        -gh-token "$GITHUB_TOKEN" \
        -gh-issue "github.com/${TRAVIS_PULL_REQUEST_SLUG}/pull/${TRAVIS_PULL_REQUEST}"

Documentation

Overview

Package covet reads version control diffs and Go coverage files to generate reports on their intersection.

Index

• type Covet
  • func Parse(options Options) (covet *Covet, err error)
  • func (c *Covet) DiffCoverageFiles() []File
  • func (c *Covet) DiffCovered() float64
  • func (c *Covet) PriorityUncoveredFiles(target uint) []File
  • func (c *Covet) ReportFileCoverage(w io.Writer, f File, options ReportFileCoverageOptions) error
  • func (c *Covet) ReportSummaryColorTerminal(w io.Writer, options ReportSummaryOptions) error
  • func (c *Covet) ReportSummaryMarkdown(w io.Writer, options ReportSummaryOptions) error
• type DiffChunk
  • func DiffChunks(file File, fileReader io.Reader) ([]DiffChunk, error)
• type File
• type Line
• type Options
• type ReportFileCoverageOptions
• type ReportSummaryOptions

Types

type Covet

type Covet struct {
	// contains filtered or unexported fields
}

Covet generates reports for a diff and coverage combination

func Parse

func Parse(options Options) (covet *Covet, err error)

Parse reads and parses both a diff file and Go coverage file, then returns a Covet instance to render reports

func (*Covet) DiffCoverageFiles

func (c *Covet) DiffCoverageFiles() []File

DiffCoverageFiles generates a report of all files that are in the diff and have coverage information. These files can be used to display diff coverage information.

func (*Covet) DiffCovered

func (c *Covet) DiffCovered() float64

DiffCovered returns the percentage of covered lines in the diff.

func (*Covet) PriorityUncoveredFiles

func (c *Covet) PriorityUncoveredFiles(target uint) []File

PriorityUncoveredFiles returns a list of Files prioritized by the largest uncovered sections of the diff. The list contains just enough Files worth of uncovered lines necessary to meet the provided 'target' coverage.

func (*Covet) ReportFileCoverage

func (c *Covet) ReportFileCoverage(w io.Writer, f File, options ReportFileCoverageOptions) error

ReportFileCoverage writes a diff-like plain text report with color to 'w'.

func (*Covet) ReportSummaryColorTerminal

func (c *Covet) ReportSummaryColorTerminal(w io.Writer, options ReportSummaryOptions) error

ReportSummaryColorTerminal writes a plain text report with color to 'w'.

func (*Covet) ReportSummaryMarkdown

func (c *Covet) ReportSummaryMarkdown(w io.Writer, options ReportSummaryOptions) error

ReportSummaryMarkdown writes a markdown report to 'w'. To capture as a string, write to a bytes.Buffer, then call buf.String().

type DiffChunk

type DiffChunk = coverfile.DiffChunk

DiffChunk is a chunk of lines parsed from a Covet report. Includes the associated beginning and end line numbers of the chunk and the diff-like lines of text from the file.

func DiffChunks

func DiffChunks(file File, fileReader io.Reader) ([]DiffChunk, error)

DiffChunks return diff-like Chunks from a covet.File and the file contents' Reader.

type File

type File = coverfile.File

File represents a file parsed in a Covet report. Includes the file name and which lines are covered.

type Line

type Line = coverfile.Line

Line represents a line in a file parsed in a Covet report

type Options

type Options struct {
	// FS is the file system to read files, Go package information, and more.
	// Defaults to hackpadfs's os.NewFS(). If on Windows, the default targets the current working directory's volume (e.g. C:\).
	FS fs.FS
	// Diff is a reader with patch or diff formatted contents
	Diff io.Reader
	// DiffBaseDir is the FS path to the repo's root directory
	DiffBaseDir string
	// GoCoverage is the FS path to a Go coverage file
	GoCoveragePath string
	// GoCoverageBaseDir is the FS path to the coverage file's module. Defaults to the coverage file's directory.
	GoCoverageBaseDir string
}

Options contains parse options

type ReportFileCoverageOptions

type ReportFileCoverageOptions struct{}

ReportFileCoverageOptions contains options to format a file coverage report. Reserved for future use.

type ReportSummaryOptions

type ReportSummaryOptions struct {
	Target uint
}

ReportSummaryOptions contains summary report options