Function getSrcBranchURL

stack/html.go:134–201

getSrcBranchURL returns a link to the source on the web and the tag name for the package version, if possible.

(c *Call)

// getSrcBranchURL returns a link to the source on the web and the tag name for
// the package version, if possible.
func getSrcBranchURL(c *Call) (template.URL, template.URL) {
	tag := ""
	if c.Location == Stdlib {
		// TODO(maruel): This is not strictly speaking correct. The remote could be
		// running a different Go version from the current executable.
		ver := runtime.Version()
		const devel = "devel +"
		if strings.HasPrefix(ver, devel) {
			ver = ver[len(devel) : len(devel)+10]
		}
		tag = url.QueryEscape(ver)
		/* #nosec G203 */
		return template.URL(fmt.Sprintf("https://github.com/golang/go/blob/%s/src/%s#L%d", tag, escape(c.RelSrcPath), c.Line)), template.URL(tag)
	}
	// TODO(maruel): Leverage Location.
	if rel := c.RelSrcPath; rel != "" {
		// Check for vendored code first.
		if i := strings.Index(rel, "/vendor/"); i != -1 {
			rel = rel[i+8:]
		}
		// Specialized support for github and golang.org. This will cover a fair
		// share of the URLs, but it'd be nice to support others too. Please submit
		// a PR (including a unit test that I was too lazy to add yet).
		switch host, rest := splitHost(rel); host {
		case "github.com":
			if parts := strings.SplitN(rest, "/", 3); len(parts) == 3 {
				p, srcTag, tag := splitTag(parts[1])
				url := fmt.Sprintf("https://github.com/%s/%s/blob/%s/%s#L%d", escape(parts[0]), p, srcTag, escape(parts[2]), c.Line)
				/* #nosec G203 */
				return template.URL(url), tag
			}
			log.Printf("problematic github.com URL: %q", rel)
		case "golang.org":
			// https://github.com/golang/build/blob/HEAD/repos/repos.go lists all
			// the golang.org/x/<foo> packages.
			if parts := strings.SplitN(rest, "/", 3); len(parts) == 3 && parts[0] == "x" {
				// parts is: "x", <project@version>, <path inside the repo>.
				p, srcTag, tag := splitTag(parts[1])
				// The source of truth is are actually go.googlesource.com, but
				// github.com has nicer syntax highlighting.
				url := fmt.Sprintf("https://github.com/golang/%s/blob/%s/%s#L%d", p, srcTag, escape(parts[2]), c.Line)
				/* #nosec G203 */
				return template.URL(url), tag
			}
			log.Printf("problematic golang.org URL: %q", rel)
		default:
			// For example gopkg.in. In this case there's no known way to find the
			// link to the source files, but we can still try to extract the version
			// if fetched from a go module.
			// Do a best effort to find a version by searching for a '@'.
			if i := strings.IndexByte(rel, '@'); i != -1 {
				if j := strings.IndexByte(rel[i:], '/'); j != -1 {
					tag = rel[i+1 : i+j]
				}
			}
		}
	}