qa: add support for missing see also error

internal/qa/qa.go

@@ -23,6 +23,7 @@ func LintCommands(commands *core.Commands) []error {
 	errors = append(errors, testArgSpecMissingError(commands)...)
 	errors = append(errors, testCommandInvalidJSONExampleError(commands)...)
 	errors = append(errors, testCommandInvalidSeeAlsoError(commands)...)
+	errors = append(errors, testAtLeastOneSeeAlsoIsPresentError(commands)...)
 
 	errors = filterIgnore(errors)
 

internal/qa/seealso.go

@@ -44,3 +44,28 @@ func testCommandInvalidSeeAlsoError(commands *core.Commands) []error {
 
 	return errors
 }
+
+type MissingSeeAlsoError struct {
+	Command *core.Command
+}
+
+func (err MissingSeeAlsoError) Error() string {
+	return fmt.Sprintf("command has no see_also commands '%s'",
+		err.Command.GetCommandLine("scw"),
+	)
+}
+
+// testAtLeastOneSeeAlsoIsPresentError testes that there is at least one SeeAlso defined by command
+func testAtLeastOneSeeAlsoIsPresentError(commands *core.Commands) []error {
+	errors := []error(nil)
+
+	for _, command := range commands.GetAll() {
+		if len(command.SeeAlsos) == 0 {
+			errors = append(errors, &MissingSeeAlsoError{Command: command})
+
+			continue
+		}
+	}
+
+	return errors
+}