chore(internal/actions): have changefinder respect v2 mods (#8014)

Change the semantics to think in dirs, which is what we are outputting. Core change is the update to the go command being run. Rest is just variable name updates to reflect data is dirs

internal/actions/cmd/changefinder/main.go

@@ -45,7 +45,7 @@ func main() {
 	}
 	logg.Printf("Root dir: %q", rootDir)
 
-	submodules, err := mods(rootDir)
+	submodulesDirs, err := modDirs(rootDir)
 	if err != nil {
 		logg.Fatal(err)
 	}
@@ -56,24 +56,24 @@ func main() {
 	}
 
 	modulesSeen := map[string]bool{}
-	updatedSubmodules := []string{}
+	updatedSubmoduleDirs := []string{}
 	for _, change := range changes {
 		if strings.HasPrefix(change, "internal") {
 			continue
 		}
-		submod, ok := owner(change, submodules)
+		submodDir, ok := owner(change, submodulesDirs)
 		if !ok {
 			logg.Printf("no module for: %s", change)
 			continue
 		}
-		if _, seen := modulesSeen[submod]; !seen {
-			logg.Printf("changes in submodule: %s", submod)
-			updatedSubmodules = append(updatedSubmodules, submod)
-			modulesSeen[submod] = true
+		if _, seen := modulesSeen[submodDir]; !seen {
+			logg.Printf("changes in submodule: %s", submodDir)
+			updatedSubmoduleDirs = append(updatedSubmoduleDirs, submodDir)
+			modulesSeen[submodDir] = true
 		}
 	}
 
-	output(updatedSubmodules)
+	output(updatedSubmoduleDirs)
 }
 
 func output(s []string) error {
@@ -92,9 +92,9 @@ func output(s []string) error {
 	return nil
 }
 
-func owner(file string, submodules []string) (string, bool) {
+func owner(file string, submoduleDirs []string) (string, bool) {
 	submod := ""
-	for _, mod := range submodules {
+	for _, mod := range submoduleDirs {
 		if strings.HasPrefix(file, mod) && len(mod) > len(submod) {
 			submod = mod
 		}
@@ -103,27 +103,28 @@ func owner(file string, submodules []string) (string, bool) {
 	return submod, submod != ""
 }
 
-func mods(dir string) (submodules []string, err error) {
-	c := exec.Command("go", "list", "-m")
+func modDirs(dir string) (submodulesDirs []string, err error) {
+	c := exec.Command("go", "list", "-m", "-f", "{{.Dir}}")
 	c.Dir = dir
 	b, err := c.Output()
 	if err != nil {
-		return submodules, err
+		return submodulesDirs, err
 	}
-	list := strings.Split(strings.TrimSpace(string(b)), "\n")
+	// Skip the root mod
+	list := strings.Split(strings.TrimSpace(string(b)), "\n")[1:]
 
-	submodules = []string{}
-	for _, mod := range list {
+	submodulesDirs = []string{}
+	for _, modPath := range list {
 		// Skip non-submodule or internal submodules.
-		if mod == "cloud.google.com/go" || strings.Contains(mod, "internal") {
+		if strings.Contains(modPath, "internal") {
 			continue
 		}
-		logg.Printf("found module: %s", mod)
-		mod = strings.TrimPrefix(mod, "cloud.google.com/go/")
-		submodules = append(submodules, mod)
+		logg.Printf("found module: %s", modPath)
+		modPath = strings.TrimPrefix(modPath, dir+"/")
+		submodulesDirs = append(submodulesDirs, modPath)
 	}
 
-	return submodules, nil
+	return submodulesDirs, nil
 }
 
 func gitFilesChanges(dir string) ([]string, error) {