SERVER-50016 Fail on missing variables files

(cherry picked from commit 5b3086d02c905b528a28d3a751af7c6b154d2f95)

1 files changed, 25 insertions, 10 deletions

diff --git a/SConstruct b/SConstruct
index a197a9f9a97..2ae9a457f47 100644
--- a/SConstruct
+++ b/SConstruct
@@ -498,15 +498,17 @@ add_option("cxx-std",
 
 def find_mongo_custom_variables():
     files = []
-    for path in sys.path:
+    paths = [path for path in sys.path if 'site_scons' in path]
+    for path in paths:
         probe = os.path.join(path, 'mongo_custom_variables.py')
         if os.path.isfile(probe):
             files.append(probe)
     return files
 
 add_option('variables-files',
-    default=find_mongo_custom_variables(),
-    help="Specify variables files to load",
+    default=[],
+    action="append",
+    help="Specify variables files to load.",
 )
 
 link_model_choices = ['auto', 'object', 'static', 'dynamic', 'dynamic-strict', 'dynamic-sdk']
@@ -665,9 +667,26 @@ def variable_distsrc_converter(val):
         return val + "/"
     return val
 
-variables_files = variable_shlex_converter(get_option('variables-files'))
-for file in variables_files:
-    print(("Using variable customization file %s" % file))
+def fatal_error(env, msg, *args):
+    print(msg.format(*args))
+    Exit(1)
+
+# Apply the default variables files, and walk the provided
+# arguments. Interpret any falsy argument (like the empty string) as
+# resetting any prior state. This makes the argument
+# --variables-files= destructive of any prior variables files
+# arguments, including the default.
+variables_files_args = get_option('variables-files')
+variables_files = find_mongo_custom_variables()
+for variables_file in variables_files_args:
+    if variables_file:
+        variables_files.append(variables_file)
+    else:
+        variables_files = []
+for vf in variables_files:
+    if not os.path.isfile(vf):
+        fatal_error(None, f"Specified variables file '{vf}' does not exist")
+    print(f"Using variable customization file {vf}")
 
 env_vars = Variables(
     files=variables_files,
@@ -1049,10 +1068,6 @@ for var in ['CC', 'CXX']:
 env.AddMethod(mongo_platform.env_os_is_wrapper, 'TargetOSIs')
 env.AddMethod(mongo_platform.env_get_os_name_wrapper, 'GetTargetOSName')
 
-def fatal_error(env, msg, *args):
-    print((msg.format(*args)))
-    Exit(1)
-
 def conf_error(env, msg, *args):
     print((msg.format(*args)))
     print(("See {0} for details".format(env.File('$CONFIGURELOG').abspath)))