Module go_coverprofile 

Go -coverprofile parser (line coverage only).

go test -coverprofile writes a mode: set|count|atomic header followed by one record per instrumented block:

mode: set
example.com/m/pkg/a.go:12.34,15.2 3 1

That is file:startLine.startCol,endLine.endCol numStmts count. A block is a source range, not a line, so each block is expanded to every line it spans and the line takes the block’s count. Where blocks overlap the larger count wins, which is the model’s rule for any line several regions cover (FileCoverage::record). A line shared by two blocks (} else {) therefore reads covered when either ran: the blocks are sub-line spans and the model is per line.

A block with no statements (an empty function body) holds nothing to execute, so it is not an executable line. The total is the number of distinct lines some block spans, not the statement-weighted figure go tool cover -func reports.

The file names are Go import paths (example.com/m/pkg/a.go), not paths on disk; module_path() reads the module an import path is rooted at so the caller can make them repo-relative.

Reference: https://go.dev/blog/cover and cmd/cover’s profile reader.

Functions

module_path

Returns the module path declared by a go.mod, or None when it has no module directive.

parse

Parses a Go coverprofile into a CoverageReport keyed by import path.