adding support for signed integers in x-field-pattern (#456)

* adding support for signed integers in x-field-pattern

* remove signed property from checksum checksum

* correcting min and max val for signed integers

MODELGUIDE.md

@@ -181,6 +181,13 @@ x-field-pattern:
       Pre-processing will write minimum and maximum values based on the length.
       Length will be ignored for mac, ipv4, ipv6 formats.
     type: integer
+  signed:
+    description: >-
+      Valid only if the format is of type integer.
+      Indicates whether the integer value is signed or unsigned.
+      If the property is not specified the value is considered as unsigned.
+      Its a boolean value which is optional in nature.
+    type: boolean
   default:
     description: >-
       The default value of the pattern value. 
@@ -344,4 +351,4 @@ ipv4:
   address:
     choice: value
     value: 0.0.0.0
-```
+```

openapiart/bundler.py

@@ -683,6 +683,19 @@ def _validate_x_field_pattern(self, xpattern_path):
                     str(xpattern_path.full_path)
                 )
             )
+        if "signed" in xpattern:
+            if xpattern["format"] != "integer":
+                self._errors.append(
+                    "signed property can only be used if the format is set to integer in property {}".format(
+                        str(xpattern_path.full_path)
+                    )
+                )
+            if not isinstance(xpattern["signed"], bool):
+                self._errors.append(
+                    "invalid value {} in {}, signed property can either be true or false".format(
+                        str(xpattern["signed"]), str(xpattern_path.full_path)
+                    )
+                )
         valid_formats = ["integer", "ipv4", "ipv6", "mac", "checksum"]
         if xpattern["format"] not in valid_formats:
             self._errors.append(
@@ -1038,6 +1051,8 @@ def _apply_common_x_field_pattern_properties(
             finalised_format = "uint32"
             if "length" in xpattern and xpattern["length"] > 32:
                 finalised_format = "uint64"
+            if xpattern.get("signed", False):
+                finalised_format = finalised_format[1:]
         elif fmt is not None:
             finalised_format = fmt
 
@@ -1047,10 +1062,22 @@ def _apply_common_x_field_pattern_properties(
             else:
                 schema["format"] = finalised_format
         if "length" in xpattern and int(xpattern["length"]) not in [32, 64]:
+            min_val = (
+                -(2 ** (int(xpattern["length"]) - 1))
+                if xpattern.get("signed", False)
+                else None
+            )
+            max_val = 2 ** int(xpattern["length"]) - 1
+            if xpattern.get("signed", False):
+                max_val = 2 ** (int(xpattern["length"]) - 1) - 1
             if property_name == "values":
-                schema["items"]["maximum"] = 2 ** int(xpattern["length"]) - 1
+                if min_val is not None:
+                    schema["items"]["minimum"] = min_val
+                schema["items"]["maximum"] = max_val
             else:
-                schema["maximum"] = 2 ** int(xpattern["length"]) - 1
+                if min_val is not None:
+                    schema["minimum"] = min_val
+                schema["maximum"] = max_val
 
     def _resolve_recursive_x_include(self, include_value):
         if "x-include" in include_value:

openapiart/tests/config/config.yaml

@@ -307,6 +307,9 @@ components:
           minimum: 64
           maximum: 9000
           x-field-uid: 52
+        signed_integer_pattern:
+          $ref: "../pattern/pattern.yaml#/components/schemas/SignedIntegerPattern"
+          x-field-uid: 53
 
     WObject:
       required: [w_name]

openapiart/tests/pattern/invalid-pattern.yaml

@@ -66,3 +66,18 @@ components:
             default: 0
             features: [count]
           x-field-uid: 7
+        signed_value_without_int:
+          x-field-pattern:
+            format: mac
+            default: "00:00:00:00:00:00"
+            features: [count, auto]
+            signed: true
+          x-field-uid: 8
+        wrong_int_signed_value:
+          x-field-pattern:
+            format: integer
+            length: 2
+            signed: 45
+            default: 0
+            features: [count]
+          x-field-uid: 9

openapiart/tests/pattern/pattern.yaml

@@ -49,3 +49,15 @@ components:
           x-field-pattern:
             format: checksum
           x-field-uid: 1
+    SignedIntegerPattern:
+      description: Test signed integer pattern
+      type: object
+      properties:
+        integer:
+          x-field-pattern:
+            format: integer
+            default: 0
+            signed: true
+            length: 8
+            features: [count]
+          x-field-uid: 1

openapiart/tests/test_integer_format.py

@@ -53,6 +53,30 @@ def test_format_integer_pattern(default_config):
     assert dec._TYPES.get("count").get("format") == "uint32"
 
 
+def test_format_signed_integer_pattern(default_config):
+    pat = default_config.signed_integer_pattern.integer
+    val = pat._TYPES.get("value")
+    assert val.get("format") == "int32"
+    assert val.get("minimum") == -128
+    assert val.get("maximum") == 127
+    inc = pat.increment
+    assert inc._TYPES.get("start").get("format") == "int32"
+    assert inc._TYPES.get("step").get("format") == "int32"
+    assert inc._TYPES.get("count").get("format") == "int32"
+    dec = pat.decrement
+    assert dec._TYPES.get("start").get("format") == "int32"
+    assert dec._TYPES.get("step").get("format") == "int32"
+    assert dec._TYPES.get("count").get("format") == "int32"
+    pat.value = -456
+    error_msg = (
+        "got -456 of type <class 'int'> , expected min -128, expected max 127"
+    )
+    with pytest.raises(Exception) as execinfo:
+        default_config.serialize("dict")
+    error_value = execinfo.value.args[0]
+    assert error_msg in error_value
+
+
 def test_format_count_pattern(default_config):
     ipv4 = default_config.ipv4_pattern.ipv4
     assert ipv4.increment._TYPES.get("count").get("format") == "uint32"

openapiart/tests/test_validate_x_field_pattern.py

@@ -26,6 +26,8 @@ def test_validate_pattern():
         "components.schemas.Config.properties.integer.x-field-pattern property using x-field-pattern with format integer must contain length property",
         "components.schemas.Config.properties.wrong.x-field-pattern has unspported format random , valid formats are ['integer', 'ipv4', 'ipv6', 'mac', 'checksum']",
         "components.schemas.Config.properties.int_128.x-field-pattern property using x-field-pattern with format integer cannot have length greater than 64",
+        "signed property can only be used if the format is set to integer in property components.schemas.Config.properties.signed_value_without_int.x-field-pattern",
+        "invalid value 45 in components.schemas.Config.properties.wrong_int_signed_value.x-field-pattern, signed property can either be true or false",
     ]
     with pytest.raises(Exception) as execinfo:
         create_openapi_artifacts(