From: Matthias Kruk <m@m10k.eu>
Date: Thu, 22 Dec 2022 06:50:18 +0000 (+0900)
Subject: toolbox.sh: Make interface methods point to error stub by default
X-Git-Url: https://git.corax.cc/?a=commitdiff_plain;h=601e20516222215b7a8f1989878fb8b8073ec23d;p=toolbox

toolbox.sh: Make interface methods point to error stub by default

Modules that declare an interface are expected to implement all
methods, prefixing method names with an underscore. However, since
there may be (partially) unimplemented interfaces, the framework
should not make such assumptions about implementations.

This commit modifies the implementation of interfaces so that
methods reference an error stub by default, which warns the caller
that the method is not implemented.
---

diff --git a/toolbox.sh b/toolbox.sh
index e9cbfd2..802c5cc 100644
--- a/toolbox.sh
+++ b/toolbox.sh
@@ -52,6 +52,7 @@ __toolbox_init() {
 	readonly -f interface
 	readonly -f implements
 	readonly -f calling_module
+	readonly -f method_not_implemented
 
 	return 0
 }
@@ -171,6 +172,16 @@ calling_module() {
 	return 0
 }
 
+method_not_implemented() {
+	local method
+
+	method="${FUNCNAME[1]}"
+	method="${method#_}"
+
+	echo "ERROR: $method: Not implemented" 1>&2
+	return 127
+}
+
 interface() {
 	local methods=("$@")
 
@@ -210,7 +221,7 @@ interface() {
 
 	# Set the entries in the vtable
 	for method in "${methods[@]}"; do
-		interface["$method"]="_${name}_$method"
+		interface["$method"]=method_not_implemented
 	done
 
 	return 0