Golang coverprofile output format


I’m trying to make sense of the -coverprofile cover.out option in go test, specifically the format of the file.

Covering server.go for example, yields the output in cover.out:

mode: set
github.com/cnuss/api_server/server.go:47.2,48.16 2 0
github.com/cnuss/api_server/server.go:52.2,53.16 2 0
github.com/cnuss/api_server/server.go:57.2,58.16 2 0
github.com/cnuss/api_server/server.go:62.2,63.16 2 0
github.com/cnuss/api_server/server.go:67.2,68.16 2 0
github.com/cnuss/api_server/server.go:72.2,73.16 2 0
github.com/cnuss/api_server/server.go:77.2,78.16 2 0
  1. What do each of the different columns mean?
  2. Is the format of the output in a “standard” format, e.g. gcov, xunit, etc. and convertable to another format?


The golang-nuts community (https://groups.google.com/forum/#!forum/golang-nuts) provided a couple useful tools for converting Go coverage into more useful formats.

JUnit Format (for summarizing test executions):

# Prerequisites
go install github.com/jstemmer/go-junit-report/v2@latest
# Tests
go test -v 2>&1 ./... | go-junit-report -set-exit-code > report.xml

Cobertura Format (for detailing code coverage):

# Prerequisites
go get github.com/axw/gocov/gocov
go get github.com/AlekSi/gocov-xml
# Coverage
go test -coverprofile=cover.out
gocov convert cover.out | gocov-xml > coverage.xml

The thread that pointed me in this direction was here:

Answered By – Christian Nuss

Answer Checked By – Candace Johnson (GoLangFix Volunteer)

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