refactor: fha calculations

pyproject.toml

@@ -102,6 +102,8 @@ dependencies = [
 
 [tool.hatch.envs.test.scripts]
 install = "make PREFIX=$VIRTUAL_ENV install"
+devinstall = "pip install -U pip && pip install -e ."
+dotest = "pytest {args}"
 clean-test = "rm -f .coverage* cobertura.xml && rm -fr .pytest_cache"
 run-unit = "pytest -m unit --no-cov --cache-clear tests"
 run-integration = "pytest -m integration --no-cov --cache-clear tests"
@@ -176,7 +178,7 @@ format = [
 	"run-docformatter",
 	"run-isort",
 ]
-lint = "ruff check {args}"
+lint = "pylint -j0 --rcfile=./pyproject.toml {args}"
 maintain = [
 	"run-mccabe",
 	"run-radon-hal",

src/ramstk/analyses/fha.py

@@ -3,15 +3,15 @@
 #       ramstk.analyses.fha.py is part of the RAMSTK Project
 #
 # All rights reserved.
-# Copyright 2019 Doyle Rowland doyle.rowland <AT> reliaqual <DOT> com
+# Copyright since 2007 Doyle Rowland doyle.rowland <AT> reliaqual <DOT> com
 """Functional Hazards Analysis (FHA) Module."""
 
 # Standard Library Imports
+import re
 from typing import Any, Dict, List
 
 # Third Party Imports
-# noinspection PyPackageRequirements
-from sympy import symbols, sympify  # type: ignore
+from sympy import SympifyError, symbols, sympify
 
 # RAMSTK Package Imports
 from ramstk.exceptions import OutOfRangeError
@@ -31,6 +31,26 @@
     "High": 5,
     "Major": 6,
 }
+VALID_VARIABLES = {
+    "hr",
+    "pi1",
+    "pi2",
+    "pi3",
+    "pi4",
+    "pi5",
+    "uf1",
+    "uf2",
+    "uf3",
+    "ui1",
+    "ui2",
+    "ui3",
+    "res1",
+    "res2",
+    "res3",
+    "res4",
+    "res5",
+    "0",
+}
 
 
 def calculate_hri(probability: str, severity: str) -> int:
@@ -50,14 +70,15 @@ def calculate_hri(probability: str, severity: str) -> int:
     except KeyError as _error:
         raise OutOfRangeError(
             (
-                f"calculate_hri() was passed an unknown hazard "
-                f"probability ({probability}) or severity ({severity}) "
-                f"description."
+                f"Invalid hazard input: probability ({probability}) or severity "
+                f"({severity}) not recognized.  Expected ranges: probability 1-5, "
+                f"severity I-IV."
             )
         ) from _error
 
 
 def calculate_user_defined(fha: Dict[str, Any]) -> Dict[str, Any]:
+    # pylint: disable=too-many-locals
     """Calculate the user-defined hazards analysis.
 
     :param fha: the user-defined functional hazards assessment dict.  The
@@ -79,82 +100,36 @@ def calculate_user_defined(fha: Dict[str, Any]) -> Dict[str, Any]:
         "uf1 uf2 uf3 ui1 ui2 ui3 res1 res2 res3 res4 res5"
     )
 
-    # pylint: disable=eval-used
-    fha["res1"] = sympify(fha["equation1"]).evalf(
-        subs={
-            uf1: fha["uf1"],
-            uf2: fha["uf2"],
-            uf3: fha["uf3"],
-            ui1: fha["ui1"],
-            ui2: fha["ui2"],
-            ui3: fha["ui3"],
-            res1: fha["res1"],
-            res2: fha["res2"],
-            res3: fha["res3"],
-            res4: fha["res4"],
-            res5: fha["res5"],
-        }
-    )
-    fha["res2"] = sympify(fha["equation2"]).evalf(
-        subs={
-            uf1: fha["uf1"],
-            uf2: fha["uf2"],
-            uf3: fha["uf3"],
-            ui1: fha["ui1"],
-            ui2: fha["ui2"],
-            ui3: fha["ui3"],
-            res1: fha["res1"],
-            res2: fha["res2"],
-            res3: fha["res3"],
-            res4: fha["res4"],
-            res5: fha["res5"],
-        }
-    )
-    fha["res3"] = sympify(fha["equation3"]).evalf(
-        subs={
-            uf1: fha["uf1"],
-            uf2: fha["uf2"],
-            uf3: fha["uf3"],
-            ui1: fha["ui1"],
-            ui2: fha["ui2"],
-            ui3: fha["ui3"],
-            res1: fha["res1"],
-            res2: fha["res2"],
-            res3: fha["res3"],
-            res4: fha["res4"],
-            res5: fha["res5"],
-        }
-    )
-    fha["res4"] = sympify(fha["equation4"]).evalf(
-        subs={
-            uf1: fha["uf1"],
-            uf2: fha["uf2"],
-            uf3: fha["uf3"],
-            ui1: fha["ui1"],
-            ui2: fha["ui2"],
-            ui3: fha["ui3"],
-            res1: fha["res1"],
-            res2: fha["res2"],
-            res3: fha["res3"],
-            res4: fha["res4"],
-            res5: fha["res5"],
-        }
-    )
-    fha["res5"] = sympify(fha["equation5"]).evalf(
-        subs={
-            uf1: fha["uf1"],
-            uf2: fha["uf2"],
-            uf3: fha["uf3"],
-            ui1: fha["ui1"],
-            ui2: fha["ui2"],
-            ui3: fha["ui3"],
-            res1: fha["res1"],
-            res2: fha["res2"],
-            res3: fha["res3"],
-            res4: fha["res4"],
-            res5: fha["res5"],
-        }
-    )
+    for _idx in range(1, 6):
+        _equation_key = f"equation{_idx}"
+        _equation = fha.get(_equation_key, "0.0")
+
+        # If the equation is empty, replace it with "0.0".
+        if not _equation.strip():
+            fha[_equation_key] = "0.0"
+        else:
+            # Validate the equation if it's not empty.
+            _do_validate_equation(_equation)
+
+        # Safely evaluate the equation using sympify
+        try:
+            fha[f"res{_idx}"] = sympify(_equation).evalf(
+                subs={
+                    uf1: fha["uf1"],
+                    uf2: fha["uf2"],
+                    uf3: fha["uf3"],
+                    ui1: fha["ui1"],
+                    ui2: fha["ui2"],
+                    ui3: fha["ui3"],
+                    res1: fha["res1"],
+                    res2: fha["res2"],
+                    res3: fha["res3"],
+                    res4: fha["res4"],
+                    res5: fha["res5"],
+                }
+            )
+        except SympifyError as exc:
+            raise ValueError(f"Invalid syntax in equation{_idx}: {_equation}") from exc
 
     return fha
 
@@ -167,13 +142,8 @@ def set_user_defined_floats(fha: Dict[str, Any], floats: List[float]) -> Dict[st
     :return: fha; the functional hazard assessment dict with updated float values.
     :rtype: dict
     """
-    _key = ""
-    for _idx in [0, 1, 2]:
-        try:
-            _key = list(fha.keys())[_idx]
-            fha[_key] = float(floats[_idx])
-        except IndexError:
-            fha[_key] = 0.0
+    for _idx in range(3):
+        fha[f"uf{_idx + 1}"] = float(floats[_idx]) if _idx < len(floats) else 0.0
 
     return fha
 
@@ -186,13 +156,8 @@ def set_user_defined_ints(fha: Dict[str, Any], ints: List[int]) -> Dict[str, Any
     :return: fha; the functional hazard assessment dict with updated integer values.
     :rtype: dict
     """
-    _key = ""
-    for _idx in [3, 4, 5]:
-        try:
-            _key = list(fha.keys())[_idx]
-            fha[_key] = int(ints[_idx - 3])
-        except IndexError:
-            fha[_key] = 0
+    for _idx in range(3):
+        fha[f"ui{_idx + 1}"] = int(ints[_idx]) if _idx < len(ints) else 0
 
     return fha
 
@@ -210,14 +175,22 @@ def set_user_defined_functions(
     :return: fha; the functional hazard assessment dict with updated functions.
     :rtype: dict
     """
-    _key = ""
-    for _idx in [6, 7, 8, 9, 10]:
+    for _idx in range(5):
         try:
-            _key = list(fha.keys())[_idx]
-            fha[_key] = (
-                "0.0" if not str(functions[_idx - 6]) else str(functions[_idx - 6])
-            )
+            _key = list(fha.keys())[_idx + 6]
+            _equation = str(functions[_idx]).strip()
+
+            # If the function is an empty string, replace it with "0.0".
+            if not _equation:
+                fha[_key] = "0.0"
+            else:
+                # Validate non-empty equations
+                _do_validate_equation(_equation)
+                fha[_key] = _equation
+
         except IndexError:
+            # If functions list doesn't contain enough elements, set the remaining
+            # to "0.0".
             fha[_key] = "0.0"
 
     return fha
@@ -236,12 +209,26 @@ def set_user_defined_results(
     :return: fha; the functional hazard assessment dict with updated results.
     :rtype: dict
     """
-    _key = ""
-    for _idx in [11, 12, 13, 14, 15]:
-        try:
-            _key = list(fha.keys())[_idx]
-            fha[_key] = results[_idx - 11]
-        except IndexError:
-            fha[_key] = 0
+    for _idx in range(5):
+        fha[f"res{_idx + 1}"] = float(results[_idx]) if _idx < len(results) else 0.0
 
     return fha
+
+
+def _do_validate_equation(equation: str) -> None:
+    """Validate that the equation contains only valid variables.
+
+    :param equation: The equation to validate.
+    :type equation: str
+    :raises ValueError: If the equation contains invalid variables.
+    """
+    # Find all the variable names in the equation (alphanumeric strings).
+    _variables = set(re.findall(r"\b\w+\b", equation))
+
+    # Check if there are any variables not in the allowed set.
+    _invalid_vars = _variables - VALID_VARIABLES
+
+    if _invalid_vars:
+        raise ValueError(
+            f"Invalid variables found in equation: {', '.join(_invalid_vars)}"
+        )