golinecov

README

golinecov

Golinecov is a tool for analyzing the coverage profiles generated by go test -coverprofile=go.cover. It can output source code annotated with coverage per-line in plain-text format, which is an alternative to generating HTML with go tool cover -html and opening it in a web brower.

Installation

go get github.com/fhs/golinecov

Example Usage

Generate the coverage profile and call it go.cover because golinecov looks for a profile with that name by default:

$ cd $GOROOT/go/src/strings
$ go test -covermode=atomic -coverprofile=go.cover

Display source of Builder.Grow annotated with coverage per-line:

$ golinecov -src -func '^Builder\.Grow$'
10883 func (b *Builder) Grow(n int) {
10883 	b.copyCheck()
    0 	if n < 0 {
    0 		panic("strings.Builder.Grow: negative count")
    - 	}
10778 	if cap(b.buf)-len(b.buf) < n {
10778 		b.grow(n)
10778 	}
    - }

Display file strings/builder.go, annotated with coverage per-line:

$ golinecov -src strings/builder.go
...
 97.4% strings/builder.go

Display summary of coverage for all files in the profile:

$ golinecov
 97.4% strings/builder.go
100.0% strings/compare.go
 95.8% strings/reader.go
 96.8% strings/replace.go
100.0% strings/search.go
 99.0% strings/strings.go

Display summary of coverage for functions matching a regular expression:

$ golinecov -func '^Builder\.'
strings/builder.go:32:	Builder.copyCheck	100.0%
strings/builder.go:46:	Builder.String		100.0%
strings/builder.go:51:	Builder.Len		100.0%
strings/builder.go:56:	Builder.Cap		100.0%
strings/builder.go:59:	Builder.Reset		100.0%
strings/builder.go:66:	Builder.grow		100.0%
strings/builder.go:75:	Builder.Grow		80.0%
strings/builder.go:87:	Builder.Write		100.0%
strings/builder.go:95:	Builder.WriteByte	100.0%
strings/builder.go:103:	Builder.WriteRune	100.0%
strings/builder.go:120:	Builder.WriteString	100.0%
total:			(statements)		97.2%

Documentation

Overview

Golinecov is a program for analyzing the coverage profiles generated by 'go test -coverprofile=go.cover'.

Golinecov was designed to explore coverage profiles from the command line or a text editor, instead of relying a web browser (to view output of 'go tool cover -html'). Golinecov can output source code annotated with coverage per-line in plain-text. It computes the coverage for a line by taking the minimum of all coverage profile blocks that contains the line. This is usually good enough for most workflows, but if it's not, the user should fallback to 'go tool cover -html'.

For usage information, please see:

golinecov -help