Added coverage computation method.

src/zoix.py

@@ -158,6 +158,73 @@ def parse_fault_report(self) -> list[Fault]:
 
             return [ Fault(**dict(zip(attributes, csv_row))) for csv_row in reader ]
 
+    @staticmethod
+    def compute_flist_coverage(fault_list : list[Fault], sff_file: pathlib.Path, formula: str, precision : int = 2, status_attribute : str = "Status") -> float:
+        """Computes the test coverage percentage as described by `formula`, which must be comprised
+        of mathematical operations of Z01X fault classes (i.e., 2 letter strings).
+
+        - Parameters:
+            - fault_list (list(Fault)): A fault-list generated after parssing Z01X fault report csv.
+            - sff_file (pathlib.Path): The fault format configuration file.
+            - formula (str): A formula which computes the coverage e.g., `"DD/(NA + DA + DN + DD)"`.
+            - precision (int): the number of decimals to consider for the coverage. Default is `2`.
+            - status_attribute (str): The attribute of the `Fault` object which represents its Z01X fault status/class.
+            By default this attribute is set to `"Status"`.
+        - Returns:
+            float: The coverage percentage i.e., the evaluated `formula`."""
+
+        # Gather fault statuses numbers.
+        fault_statuses = dict()
+
+        for fault in fault_list:
+
+            status = fault.get(status_attribute)
+            if status in fault_statuses:
+                fault_statuses[status] += 1
+            else:
+                fault_statuses[status] = 1
+
+
+        # Parse StatusGroups section.
+        with open(sff_file) as config:
+
+            try:
+                status_groups_raw = re.search(
+                    r"StatusGroups\n\s*{([^}]+)\s*}",
+                    config.read(),
+                    re.MULTILINE).group(1).splitlines()
+
+            except AttributeError:
+                log.critical(f"Unable to extract StatusGroups segment from {sff_file}. Exiting...")
+                exit(1)
+
+        # Remove empty lines if any.
+        status_groups_raw = list(filter(lambda x : len(x), map(str.strip, status_groups_raw)))
+        status_groups = dict()
+
+        for line in status_groups_raw:
+
+            group, *statuses = re.findall(r"([A-Z]{2})", line)
+
+            status_groups[group] = 0
+
+            for status in statuses:
+                if status in fault_statuses:
+                    status_groups[group] += fault_statuses[status]
+
+
+        # Finally get any group only present
+        # in the formula and set it to 0.
+        non_present_statuses = dict()
+
+        for status in re.findall(r"[A-Z]{2}", formula):
+
+            if status not in fault_statuses.keys() and \
+            status not in status_groups.keys():
+                non_present_statuses[status] = 0
+
+        return round(eval(formula, {**fault_statuses, **status_groups, **non_present_statuses}), precision)
+
 class ZoixInvoker():
     """A wrapper class to be used in handling calls to VCS-Z01X."""
     def __init__(self) -> "ZoixInvoker":