Fix test errors produced by JSON schema after rebase

- Modified the expected error code in some of the test cases. The error
  message is now issued by the JSON validator.

- Stop validation code being called if no application configuration is
  given to validate.

- Change test mock code to check for specific calls, instead of number of
  calls.

- Derive absolute paths for JSON schema files before loading them, which
  seems to work better with the URI path resolution of the schema parser.

tools/config/__init__.py

@@ -16,7 +16,9 @@ limitations under the License.
 """
 
 from copy import deepcopy
+from six import moves
 import json
+import six
 import os
 from os.path import dirname, abspath, exists, join, isabs
 import sys
@@ -407,13 +409,18 @@ class Config(object):
                 ConfigException("Could not parse mbed app configuration from %s"
                                 % self.app_config_location))
 
-        # Validate the format of the JSON file based on the schema_app.json
-        schema_root = os.path.dirname(__file__)
-        schema_path = os.path.join(schema_root, "schema_app.json")
-        schema_file = json_file_to_dict(schema_path)
 
-        resolver = RefResolver("file://{}/".format(schema_root), schema_file)
+        if self.app_config_location is not None:
-        validator = Draft4Validator(schema_file, resolver=resolver)
+            # Validate the format of the JSON file based on schema_app.json
+            schema_root = os.path.dirname(os.path.abspath(__file__))
+            schema_path = os.path.join(schema_root, "schema_app.json")
+            schema      = json_file_to_dict(schema_path)
+
+            url = moves.urllib.request.pathname2url(schema_path)
+            uri = moves.urllib_parse.urljoin("file://", url)
+
+            resolver = RefResolver(uri, schema)
+            validator = Draft4Validator(schema, resolver=resolver)
 
             errors = sorted(validator.iter_errors(self.app_config_data))
 
@@ -470,12 +477,14 @@ class Config(object):
                 continue
 
             # Validate the format of the JSON file based on the schema_lib.json
-            schema_root = os.path.dirname(__file__)
+            schema_root = os.path.dirname(os.path.abspath(__file__))
             schema_path = os.path.join(schema_root, "schema_lib.json")
             schema_file = json_file_to_dict(schema_path)
 
-            resolver = RefResolver("file://{}/".format(schema_root),
+            url = moves.urllib.request.pathname2url(schema_path)
-                                   schema_file)
+            uri = moves.urllib_parse.urljoin("file://", url)
+
+            resolver = RefResolver(uri, schema_file)
             validator = Draft4Validator(schema_file, resolver=resolver)
 
             errors = sorted(validator.iter_errors(cfg))

tools/config/definitions.json

@@ -53,7 +53,8 @@
         "type": [
           "integer",
           "string",
-          "boolean"
+          "boolean",
+          "null"
         ]
       },
       "required": {
@@ -70,7 +71,8 @@
     "type": [
       "string",
       "integer",
-      "boolean"
+      "boolean",
+      "null"
     ]
   },
   "config_parameter_base": {

tools/config/schema_app.json

@@ -5,16 +5,16 @@
   "type": "object",
   "properties": {
     "name": {
-      "$ref": "file:definitions.json#/name_definition"
+      "$ref": "definitions.json#/name_definition"
     },
     "config": {
-      "$ref": "file:definitions.json#/config_definition"
+      "$ref": "definitions.json#/config_definition"
     },
     "target_overrides": {
-      "$ref": "file:definitions.json#/target_overrides_definition"
+      "$ref": "definitions.json#/target_overrides_definition"
     },
     "macros": {
-      "$ref": "file:definitions.json#/macro_definition"
+      "$ref": "definitions.json#/macro_definition"
     },
     "artifact_name": {
       "type": "string"

tools/config/schema_lib.json

@@ -5,16 +5,16 @@
   "type": "object",
   "properties": {
     "name": {
-      "$ref": "file:definitions.json#/name_definition"
+      "$ref": "definitions.json#/name_definition"
     },
     "config": {
-      "$ref": "file:definitions.json#/config_definition"
+      "$ref": "definitions.json#/config_definition"
     },
     "target_overrides": {
-      "$ref": "file:definitions.json#/target_overrides_definition"
+      "$ref": "definitions.json#/target_overrides_definition"
     },
     "macros": {
-      "$ref": "file:definitions.json#/macro_definition"
+      "$ref": "definitions.json#/macro_definition"
     }
   },
   "required": [

tools/test/config/config_test.py

@@ -108,7 +108,8 @@ def test_init_app_config(target):
 
         config = Config(target, app_config=app_config)
 
-        mock_json_file_to_dict.assert_called_with(app_config)
+        mock_json_file_to_dict.assert_any_call("app_config")
+
         assert config.app_config_data == mock_return
 
 
@@ -149,7 +150,7 @@ def test_init_no_app_config_with_dir(target):
         config = Config(target, [directory])
 
         mock_isfile.assert_called_with(path)
-        mock_json_file_to_dict.assert_called_once_with(path)
+        mock_json_file_to_dict.assert_any_call(path)
         assert config.app_config_data == mock_return
 
 
@@ -171,5 +172,5 @@ def test_init_override_app_config(target):
 
         config = Config(target, [directory], app_config=app_config)
 
-        mock_json_file_to_dict.assert_called_once_with(app_config)
+        mock_json_file_to_dict.assert_any_call(app_config)
         assert config.app_config_data == mock_return

tools/test/config/invalid_key/test_data.json

@@ -1,5 +1,5 @@
 {
     "K64F": {
-        "exception_msg": "Unknown key(s)"
+        "exception_msg": "Additional properties are not allowed ('unknown_key' was unexpected)"
     }
 }

tools/test/config/invalid_key_lib/test_data.json

@@ -1,5 +1,5 @@
 {
     "K64F": {
-        "exception_msg": "Unknown key(s)"
+        "exception_msg": "Additional properties are not allowed ('unknown_key' was unexpected)"
     }
 }