Fix support for go1.18 (#466)

Author: vearutop

CHANGELOG.md

@@ -15,6 +15,10 @@ This document is formatted according to the principles of [Keep A CHANGELOG](htt
 - Changed underlying cobra command setup to return errors instead of calling `os.Exit` directly to enable simpler testing. ([454](https://github.com/cucumber/godog/pull/454) - [mxygem])
 - Remove use of deprecated methods from `_examples`. ([460](https://github.com/cucumber/godog/pull/460) - [ricardogarfe])
 
+### Fixed
+
+- Support for go1.18 in `godog` cli mode ([466](https://github.com/cucumber/godog/pull/466) - [vearutop])
+
 ## [v0.12.4]
 
 ### Added

internal/builder/builder.go

@@ -205,6 +205,10 @@ func Build(bin string) error {
 		"-complete",
 	}
 
+	if err := filterImportCfg(compilerCfg); err != nil {
+		return err
+	}
+
 	args = append(args, "-pack", testmain)
 	cmd := exec.Command(compiler, args...)
 	cmd.Env = os.Environ()
@@ -234,6 +238,27 @@ func Build(bin string) error {
 	return nil
 }
 
+// filterImportCfg strips unsupported lines from imports configuration.
+func filterImportCfg(path string) error {
+	orig, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("failed to read %s: %w", path, err)
+	}
+
+	res := ""
+	for _, l := range strings.Split(string(orig), "\n") {
+		if !strings.HasPrefix(l, "modinfo") {
+			res += l + "\n"
+		}
+	}
+	err = ioutil.WriteFile(path, []byte(res), 0600)
+	if err != nil {
+		return fmt.Errorf("failed to write %s: %w", path, err)
+	}
+
+	return nil
+}
+
 func maybeVendoredGodog() *build.Package {
 	dir, err := filepath.Abs(".")
 	if err != nil {