We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Unsupported testlist versions should trigger an error
#2316 (included in [cime5.4.0-alpha.25](https://github.com/ESMCI/cime/releases/tag/cime5.4.0-alpha.25)) dropped support for v1 of the testlist XML file, but trying to run a test suite from a v1.0 testlist file results in no tests being run instead of a traceable error.

For example, POP's test list in both `cesm2_0_alpha10b` and `cesm2_0_alpha10c` is still v1.0, and running `aux_pop` on cheyenne results in:

```
$ qcmd -- ./create_test --parallel-jobs 4 --proc-pool 36 --xml-machine cheyenne --xml-compiler intel --xml-category aux_pop --queue economy --walltime 2:00 --project P93300070 --test-root /glade/scratch/mlevy/tests/empty_testlist
Submitting command to PBS using account P93300070:
    ./create_test --parallel-jobs 4 --proc-pool 36 --xml-machine cheyenne --xml-compiler intel --xml-category aux_pop --queue economy --walltime 2:00 --project P93300070 --test-root /glade/scratch/mlevy/tests/empty_testlist

Waiting for job 7572427.chadmin1 to start ...


Testnames: []
RUNNING TESTS:
Due to presence of batch system, create_test will exit before tests are complete.
To force create_test to wait for full completion, use --wait
At test-scheduler close, state is:
test-scheduler took 0.01305103302 seconds
```

Even though there are 35 tests defined in the no-longer-supported XML format.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `scripts/lib/CIME/XML/testlist.py`
Content:
```
1 """
2 Interface to the config_files.xml file.  This class inherits from generic_xml.py
3 It supports version 2.0 of the testlist.xml file
4 
5 In version 2 of the file options can be specified to further refine a test or
6 set of tests. They can be specified either at the top level, in which case they
7 apply to all machines/compilers for this test:
8 
9 <test ...>
10   <options>
11     <option name="wallclock">00:20</option>
12   </options>
13   ...
14 </test>
15 
16 or at the level of a particular machine/compiler:
17 
18 <test ...>
19   <machines>
20     <machine ...>
21       <options>
22         <option name="wallclock">00:20</option>
23       </options>
24     </machine>
25   </machines>
26 </test>
27 
28 Currently supported options are:
29 
30 - walltime: sets the wallclock limit in the queuing system
31 
32 - memleak_tolerance: specifies the relative memory growth expected for this test
33 
34 - comment: has no effect, but is written out when printing the test list
35 
36 """
37 from CIME.XML.standard_module_setup import *
38 
39 from CIME.XML.generic_xml import GenericXML
40 from CIME.XML.files import Files
41 
42 logger = logging.getLogger(__name__)
43 
44 class Testlist(GenericXML):
45 
46     def __init__(self,infile, files=None):
47         """
48         initialize an object
49         """
50         schema = None
51         if files is None:
52             files = Files()
53         schema = files.get_schema("TESTS_SPEC_FILE")
54         GenericXML.__init__(self, infile, schema=schema)
55 
56     def get_tests(self, machine=None, category=None, compiler=None, compset=None, grid=None, supported_only=False):
57         tests = []
58         attributes = {}
59         if compset is not None:
60             attributes['compset'] = compset
61         if grid is not None:
62             attributes['grid'] = grid
63 
64         testnodes = self.get_children("test", attributes=attributes)
65 
66         machatts = {}
67         if machine is not None:
68             machatts["name"]      = machine
69         if category is not None:
70             machatts["category"]  = category
71         if compiler is not None:
72             machatts["compiler"]  = compiler
73 
74 
75         for tnode in testnodes:
76             if supported_only and self.has(tnode, "supported") and self.get(tnode, "supported") == 'false':
77                 continue
78 
79             machnode = self.get_optional_child("machines", root=tnode)
80             machnodes = None if machnode is None else self.get_children("machine",machatts,root=machnode)
81             if machnodes:
82                 this_test_node = {}
83                 for key, value in self.attrib(tnode).items():
84                     if key == "name":
85                         this_test_node["testname"] = value
86                     else:
87                         this_test_node[key] = value
88 
89 
90 
91                 # Get options that apply to all machines/compilers for this test
92                 options = self.get_children("options", root=tnode)
93                 if len(options) > 0:
94                     optionnodes = self.get_children("option", root=options[0])
95                 else:
96                     optionnodes = []
97                 for mach in machnodes:
98                     # this_test_node can include multiple tests
99                     this_test = dict(this_test_node)
100                     for key, value in self.attrib(mach).items():
101                         if key == "name":
102                             this_test["machine"] = value
103                         else:
104                             this_test[key] = value
105                     this_test["options"] = {}
106 
107                     for onode in optionnodes:
108                         this_test['options'][self.get(onode, 'name')] = self.text(onode)
109 
110                     # Now get options specific to this machine/compiler
111                     options = self.get_optional_child("options", root=mach)
112                     optionnodes = [] if options is None else self.get_children("option", root=options)
113                     for onode in optionnodes:
114                         this_test['options'][self.get(onode, 'name')] = self.text(onode)
115 
116                     tests.append(this_test)
117 
118         return tests
119
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/scripts/lib/CIME/XML/testlist.py b/scripts/lib/CIME/XML/testlist.py
--- a/scripts/lib/CIME/XML/testlist.py
+++ b/scripts/lib/CIME/XML/testlist.py
@@ -52,6 +52,8 @@
             files = Files()
         schema = files.get_schema("TESTS_SPEC_FILE")
         GenericXML.__init__(self, infile, schema=schema)
+        expect(self.get_version() >= 2.0,
+               "{} is an unsupported version of the testfile format and will be ignored".format(infile))
 
     def get_tests(self, machine=None, category=None, compiler=None, compset=None, grid=None, supported_only=False):
         tests = []

{"golden_diff": "diff --git a/scripts/lib/CIME/XML/testlist.py b/scripts/lib/CIME/XML/testlist.py\n--- a/scripts/lib/CIME/XML/testlist.py\n+++ b/scripts/lib/CIME/XML/testlist.py\n@@ -52,6 +52,8 @@\n             files = Files()\n         schema = files.get_schema(\"TESTS_SPEC_FILE\")\n         GenericXML.__init__(self, infile, schema=schema)\n+        expect(self.get_version() >= 2.0,\n+               \"{} is an unsupported version of the testfile format and will be ignored\".format(infile))\n \n     def get_tests(self, machine=None, category=None, compiler=None, compset=None, grid=None, supported_only=False):\n         tests = []\n", "issue": "Unsupported testlist versions should trigger an error\n#2316 (included in [cime5.4.0-alpha.25](https://github.com/ESMCI/cime/releases/tag/cime5.4.0-alpha.25)) dropped support for v1 of the testlist XML file, but trying to run a test suite from a v1.0 testlist file results in no tests being run instead of a traceable error.\r\n\r\nFor example, POP's test list in both `cesm2_0_alpha10b` and `cesm2_0_alpha10c` is still v1.0, and running `aux_pop` on cheyenne results in:\r\n\r\n```\r\n$ qcmd -- ./create_test --parallel-jobs 4 --proc-pool 36 --xml-machine cheyenne --xml-compiler intel --xml-category aux_pop --queue economy --walltime 2:00 --project P93300070 --test-root /glade/scratch/mlevy/tests/empty_testlist\r\nSubmitting command to PBS using account P93300070:\r\n    ./create_test --parallel-jobs 4 --proc-pool 36 --xml-machine cheyenne --xml-compiler intel --xml-category aux_pop --queue economy --walltime 2:00 --project P93300070 --test-root /glade/scratch/mlevy/tests/empty_testlist\r\n\r\nWaiting for job 7572427.chadmin1 to start ...\r\n\r\n\r\nTestnames: []\r\nRUNNING TESTS:\r\nDue to presence of batch system, create_test will exit before tests are complete.\r\nTo force create_test to wait for full completion, use --wait\r\nAt test-scheduler close, state is:\r\ntest-scheduler took 0.01305103302 seconds\r\n```\r\n\r\nEven though there are 35 tests defined in the no-longer-supported XML format.\n", "before_files": [{"content": "\"\"\"\nInterface to the config_files.xml file.  This class inherits from generic_xml.py\nIt supports version 2.0 of the testlist.xml file\n\nIn version 2 of the file options can be specified to further refine a test or\nset of tests. They can be specified either at the top level, in which case they\napply to all machines/compilers for this test:\n\n<test ...>\n  <options>\n    <option name=\"wallclock\">00:20</option>\n  </options>\n  ...\n</test>\n\nor at the level of a particular machine/compiler:\n\n<test ...>\n  <machines>\n    <machine ...>\n      <options>\n        <option name=\"wallclock\">00:20</option>\n      </options>\n    </machine>\n  </machines>\n</test>\n\nCurrently supported options are:\n\n- walltime: sets the wallclock limit in the queuing system\n\n- memleak_tolerance: specifies the relative memory growth expected for this test\n\n- comment: has no effect, but is written out when printing the test list\n\n\"\"\"\nfrom CIME.XML.standard_module_setup import *\n\nfrom CIME.XML.generic_xml import GenericXML\nfrom CIME.XML.files import Files\n\nlogger = logging.getLogger(__name__)\n\nclass Testlist(GenericXML):\n\n    def __init__(self,infile, files=None):\n        \"\"\"\n        initialize an object\n        \"\"\"\n        schema = None\n        if files is None:\n            files = Files()\n        schema = files.get_schema(\"TESTS_SPEC_FILE\")\n        GenericXML.__init__(self, infile, schema=schema)\n\n    def get_tests(self, machine=None, category=None, compiler=None, compset=None, grid=None, supported_only=False):\n        tests = []\n        attributes = {}\n        if compset is not None:\n            attributes['compset'] = compset\n        if grid is not None:\n            attributes['grid'] = grid\n\n        testnodes = self.get_children(\"test\", attributes=attributes)\n\n        machatts = {}\n        if machine is not None:\n            machatts[\"name\"]      = machine\n        if category is not None:\n            machatts[\"category\"]  = category\n        if compiler is not None:\n            machatts[\"compiler\"]  = compiler\n\n\n        for tnode in testnodes:\n            if supported_only and self.has(tnode, \"supported\") and self.get(tnode, \"supported\") == 'false':\n                continue\n\n            machnode = self.get_optional_child(\"machines\", root=tnode)\n            machnodes = None if machnode is None else self.get_children(\"machine\",machatts,root=machnode)\n            if machnodes:\n                this_test_node = {}\n                for key, value in self.attrib(tnode).items():\n                    if key == \"name\":\n                        this_test_node[\"testname\"] = value\n                    else:\n                        this_test_node[key] = value\n\n\n\n                # Get options that apply to all machines/compilers for this test\n                options = self.get_children(\"options\", root=tnode)\n                if len(options) > 0:\n                    optionnodes = self.get_children(\"option\", root=options[0])\n                else:\n                    optionnodes = []\n                for mach in machnodes:\n                    # this_test_node can include multiple tests\n                    this_test = dict(this_test_node)\n                    for key, value in self.attrib(mach).items():\n                        if key == \"name\":\n                            this_test[\"machine\"] = value\n                        else:\n                            this_test[key] = value\n                    this_test[\"options\"] = {}\n\n                    for onode in optionnodes:\n                        this_test['options'][self.get(onode, 'name')] = self.text(onode)\n\n                    # Now get options specific to this machine/compiler\n                    options = self.get_optional_child(\"options\", root=mach)\n                    optionnodes = [] if options is None else self.get_children(\"option\", root=options)\n                    for onode in optionnodes:\n                        this_test['options'][self.get(onode, 'name')] = self.text(onode)\n\n                    tests.append(this_test)\n\n        return tests\n", "path": "scripts/lib/CIME/XML/testlist.py"}], "after_files": [{"content": "\"\"\"\nInterface to the config_files.xml file.  This class inherits from generic_xml.py\nIt supports version 2.0 of the testlist.xml file\n\nIn version 2 of the file options can be specified to further refine a test or\nset of tests. They can be specified either at the top level, in which case they\napply to all machines/compilers for this test:\n\n<test ...>\n  <options>\n    <option name=\"wallclock\">00:20</option>\n  </options>\n  ...\n</test>\n\nor at the level of a particular machine/compiler:\n\n<test ...>\n  <machines>\n    <machine ...>\n      <options>\n        <option name=\"wallclock\">00:20</option>\n      </options>\n    </machine>\n  </machines>\n</test>\n\nCurrently supported options are:\n\n- walltime: sets the wallclock limit in the queuing system\n\n- memleak_tolerance: specifies the relative memory growth expected for this test\n\n- comment: has no effect, but is written out when printing the test list\n\n\"\"\"\nfrom CIME.XML.standard_module_setup import *\n\nfrom CIME.XML.generic_xml import GenericXML\nfrom CIME.XML.files import Files\n\nlogger = logging.getLogger(__name__)\n\nclass Testlist(GenericXML):\n\n    def __init__(self,infile, files=None):\n        \"\"\"\n        initialize an object\n        \"\"\"\n        schema = None\n        if files is None:\n            files = Files()\n        schema = files.get_schema(\"TESTS_SPEC_FILE\")\n        GenericXML.__init__(self, infile, schema=schema)\n        expect(self.get_version() >= 2.0,\n               \"{} is an unsupported version of the testfile format and will be ignored\".format(infile))\n\n    def get_tests(self, machine=None, category=None, compiler=None, compset=None, grid=None, supported_only=False):\n        tests = []\n        attributes = {}\n        if compset is not None:\n            attributes['compset'] = compset\n        if grid is not None:\n            attributes['grid'] = grid\n\n        testnodes = self.get_children(\"test\", attributes=attributes)\n\n        machatts = {}\n        if machine is not None:\n            machatts[\"name\"]      = machine\n        if category is not None:\n            machatts[\"category\"]  = category\n        if compiler is not None:\n            machatts[\"compiler\"]  = compiler\n\n\n        for tnode in testnodes:\n            if supported_only and self.has(tnode, \"supported\") and self.get(tnode, \"supported\") == 'false':\n                continue\n\n            machnode = self.get_optional_child(\"machines\", root=tnode)\n            machnodes = None if machnode is None else self.get_children(\"machine\",machatts,root=machnode)\n            if machnodes:\n                this_test_node = {}\n                for key, value in self.attrib(tnode).items():\n                    if key == \"name\":\n                        this_test_node[\"testname\"] = value\n                    else:\n                        this_test_node[key] = value\n\n\n\n                # Get options that apply to all machines/compilers for this test\n                options = self.get_children(\"options\", root=tnode)\n                if len(options) > 0:\n                    optionnodes = self.get_children(\"option\", root=options[0])\n                else:\n                    optionnodes = []\n                for mach in machnodes:\n                    # this_test_node can include multiple tests\n                    this_test = dict(this_test_node)\n                    for key, value in self.attrib(mach).items():\n                        if key == \"name\":\n                            this_test[\"machine\"] = value\n                        else:\n                            this_test[key] = value\n                    this_test[\"options\"] = {}\n\n                    for onode in optionnodes:\n                        this_test['options'][self.get(onode, 'name')] = self.text(onode)\n\n                    # Now get options specific to this machine/compiler\n                    options = self.get_optional_child(\"options\", root=mach)\n                    optionnodes = [] if options is None else self.get_children(\"option\", root=options)\n                    for onode in optionnodes:\n                        this_test['options'][self.get(onode, 'name')] = self.text(onode)\n\n                    tests.append(this_test)\n\n        return tests\n", "path": "scripts/lib/CIME/XML/testlist.py"}]}