Backported: SCons: Validate dependencies for linked multimedia modules

This is still a bit hacky and eventually we should rework the way we handle
optional dependencies (especially with regard to builtin/system libs), but
it's a simple first step.
- akien-mga
7c74312217

SConstruct

@@ -94,6 +94,7 @@ env_base.__class__.add_library = methods.add_library
 env_base.__class__.add_program = methods.add_program
 env_base.__class__.CommandNoCache = methods.CommandNoCache
 env_base.__class__.disable_warnings = methods.disable_warnings
+env_base.__class__.module_check_dependencies = methods.module_check_dependencies
 
 env_base["x86_libtheora_opt_gcc"] = False
 env_base["x86_libtheora_opt_vc"] = False
@@ -576,19 +577,7 @@ if selected_platform in platform_list:
         env.current_module = name
         import config
 
-        # can_build changed number of arguments between 3.0 (1) and 3.1 (2),
-        # so try both to preserve compatibility for 3.0 modules
-        can_build = False
-        try:
-            can_build = config.can_build(env, selected_platform)
-        except TypeError:
-            print(
-                "Warning: module '%s' uses a deprecated `can_build` "
-                "signature in its config.py file, it should be "
-                "`can_build(env, platform)`." % x
-            )
-            can_build = config.can_build(selected_platform)
-        if can_build:
+        if config.can_build(env, selected_platform):
             config.configure(env)
             # Get doc classes paths (if present)
             try:
@@ -635,6 +624,7 @@ if selected_platform in platform_list:
         env.Append(CPPDEFINES=["PTRCALL_ENABLED"])
     if env["tools"]:
         env.Append(CPPDEFINES=["TOOLS_ENABLED"])
+
     if env["disable_3d"]:
         if env["tools"]:
             print(
@@ -644,6 +634,7 @@ if selected_platform in platform_list:
             sys.exit(255)
         else:
             env.Append(CPPDEFINES=["_3D_DISABLED"])
+
     if env["disable_advanced_gui"]:
         if env["tools"]:
             print(
@@ -657,14 +648,9 @@ if selected_platform in platform_list:
         env.Append(CPPDEFINES=["MINIZIP_ENABLED"])
 
     editor_module_list = ["freetype"]
-    for x in editor_module_list:
-        if not env["module_" + x + "_enabled"]:
-            if env["tools"]:
-                print(
-                    "Build option 'module_" + x + "_enabled=no' cannot be used with 'tools=yes' (editor), "
-                    "only with 'tools=no' (export template)."
-                )
-                sys.exit(255)
+    if env["tools"] and not env.module_check_dependencies("tools", editor_module_list):
+        print("The editor (tools=yes) can't be built if it's dependencies are not satisfied! Stopping.")
+        sys.exit(255)
 
     if not env["verbose"]:
         methods.no_verbose(sys, env)
@@ -694,8 +680,10 @@ if selected_platform in platform_list:
     SConscript("core/SCsub")
     SConscript("servers/SCsub")
     SConscript("scene/SCsub")
+
     if env["tools"]:
         SConscript("editor/SCsub")
+
     SConscript("drivers/SCsub")
 
     SConscript("platform/SCsub")

methods.py

@@ -306,6 +306,28 @@ def convert_custom_modules_path(path):
 def disable_module(self):
     self.disabled_modules.append(self.current_module)
 
+def module_check_dependencies(self, module, dependencies):
+    """
+    Checks if module dependencies are enabled for a given module,
+    and prints a warning if they aren't.
+    Meant to be used in module `can_build` methods.
+    Returns a boolean (True if dependencies are satisfied).
+    """
+    missing_deps = []
+    for dep in dependencies:
+        opt = "module_{}_enabled".format(dep)
+        if not opt in self or not self[opt]:
+            missing_deps.append(dep)
+
+    if missing_deps != []:
+        print(
+            "Disabling '{}' module as the following dependencies are not satisfied: {}".format(
+                module, ", ".join(missing_deps)
+            )
+        )
+        return False
+    else:
+        return True
 
 def use_windows_spawn_fix(self, platform=None):
 

modules/freetype/config.py

@@ -1,3 +1,4 @@
+
 def can_build(env, platform):
     return True
 

modules/opus/config.py

@@ -1,5 +1,7 @@
+
+
 def can_build(env, platform):
-    return True
+    return env.module_check_dependencies("opus", ["ogg"])
 
 
 def configure(env):

modules/theora/config.py

@@ -1,5 +1,6 @@
+
 def can_build(env, platform):
-    return True
+    return env.module_check_dependencies("theora", ["ogg", "vorbis"])
 
 
 def configure(env):

modules/vorbis/config.py

@@ -1,5 +1,6 @@
+
 def can_build(env, platform):
-    return True
+        return env.module_check_dependencies("vorbis", ["ogg"])
 
 
 def configure(env):