#23 restrict equalityoperator mutator (#41)

* ArithmeticOp: pass the whole level * Add min size to level arrays and mandatory name * Move arithmetic ops to map * Add test for arithmetic operator * Restrict EqualityOperator Observed mutation score (equality-operator-mutator.ts): 85.71% * Formatting fixes * Formatting fixes and removed dead code * Update arithmetic-operator-mutator.ts and equality-operator-mutator.ts to comply with the changes to node-mutator.ts. Coded it such that `undefined` results in allowing everything since otherwise setting no MutationLevel results in blocking every mutator. --------- Co-authored-by: Danut Copae <[email protected]> Co-authored-by: Ivo_Broekhof <[email protected]>
brokhiv · Nov 22, 2023 · f9fbcf6 · f9fbcf6
1 parent 9ec5d92
commit f9fbcf6
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Showing 6 changed files with 115 additions and 23 deletions.
diff --git a/packages/api/schema/stryker-core.json b/packages/api/schema/stryker-core.json
@@ -258,7 +258,7 @@
       "title": "MutationLevel",
       "type": "object",
       "default": {},
-      "additionalProperties": false,
+      "required": ["name"],
       "properties": {
         "name": {
           "description": "Name of the mutation level.",
@@ -310,6 +310,7 @@
       "title": "ArithmeticOperator",
       "type": "array",
       "uniqueItems": true,
+      "minItems": 1,
       "default": [],
       "items": {
         "anyOf": [
@@ -347,6 +348,7 @@
       "description": "EmptyArray := \nEmptyArrayConstructor := \nFilledArray := \nFilledArrayConstructor := ",
       "uniqueItems": true,
       "default": [],
+      "minItems": 1,
       "items": {
         "anyOf": [
           {
@@ -383,6 +385,7 @@
       "type": "array",
       "uniqueItems": true,
       "default": [],
+      "minItems": 1,
       "items": {
         "anyOf": [
           {
@@ -408,6 +411,7 @@
       "type": "array",
       "default": [],
       "uniqueItems": true,
+      "minItems": 1,
       "items": {
         "anyOf": [
           {
@@ -453,6 +457,7 @@
       "type": "array",
       "uniqueItems": true,
       "default": [],
+      "minItems": 1,
       "items": {
         "anyOf": [
           {
@@ -522,6 +527,7 @@
       "title": "LogicalOperator",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [
@@ -547,6 +553,7 @@
       "title": "MethodExpression",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [
@@ -633,6 +640,7 @@
       "title": "OptionalChaining",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [
@@ -658,6 +666,7 @@
       "title": "StringLiteral",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [
@@ -683,6 +692,7 @@
       "title": "UnaryOperator",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [
@@ -708,6 +718,7 @@
       "title": "UpdateOperator",
       "type": "array",
       "default": [],
+      "minItems": 1,
       "uniqueItems": true,
       "items": {
         "anyOf": [

diff --git a/packages/instrumenter/src/mutators/arithmetic-operator-mutator.ts b/packages/instrumenter/src/mutators/arithmetic-operator-mutator.ts
@@ -5,26 +5,36 @@ import { deepCloneNode } from '../util/index.js';
 import { NodeMutator } from './node-mutator.js';
 
 const arithmeticOperatorReplacements = Object.freeze({
-  '+': '-',
-  '-': '+',
-  '*': '/',
-  '/': '*',
-  '%': '*',
+  '+': { replacement: '-', mutatorName: '+To-' },
+  '-': { replacement: '+', mutatorName: '-To+' },
+  '*': { replacement: '/', mutatorName: '*To/' },
+  '/': { replacement: '*', mutatorName: '/To*' },
+  '%': { replacement: '*', mutatorName: '%To*' },
 } as const);
 
 export const arithmeticOperatorMutator: NodeMutator = {
   name: 'ArithmeticOperator',
 
-  *mutate(path) {
-    if (path.isBinaryExpression() && isSupported(path.node.operator, path.node)) {
-      const mutatedOperator = arithmeticOperatorReplacements[path.node.operator];
+  *mutate(path, options) {
+    if (path.isBinaryExpression() && isSupported(path.node.operator, path.node) && isInMutationLevel(path.node, options)) {
+      const mutatedOperator = arithmeticOperatorReplacements[path.node.operator].replacement;
       const replacement = deepCloneNode(path.node);
       replacement.operator = mutatedOperator;
       yield replacement;
     }
   },
 };
 
+function isInMutationLevel(node: types.BinaryExpression, operations: string[] | undefined): boolean {
+  // No mutation level specified, so allow everything
+  if (operations === undefined) {
+    return true;
+  }
+
+  const mutatedOperator = arithmeticOperatorReplacements[node.operator as keyof typeof arithmeticOperatorReplacements].mutatorName;
+  return operations.some((op) => op === mutatedOperator) ?? false;
+}
+
 function isSupported(operator: string, node: types.BinaryExpression): operator is keyof typeof arithmeticOperatorReplacements {
   if (!Object.keys(arithmeticOperatorReplacements).includes(operator)) {
     return false;

diff --git a/packages/instrumenter/src/mutators/equality-operator-mutator.ts b/packages/instrumenter/src/mutators/equality-operator-mutator.ts
@@ -1,18 +1,30 @@
-import babel from '@babel/core';
+import babel, { types } from '@babel/core';
 
 import { NodeMutator } from './node-mutator.js';
 
 const { types: t } = babel;
 
 const operators = {
-  '<': ['<=', '>='],
-  '<=': ['<', '>'],
-  '>': ['>=', '<='],
-  '>=': ['>', '<'],
-  '==': ['!='],
-  '!=': ['=='],
-  '===': ['!=='],
-  '!==': ['==='],
+  '<': [
+    { replacement: '<=', mutatorName: '<To<=' },
+    { replacement: '>=', mutatorName: '<To>=' },
+  ],
+  '<=': [
+    { replacement: '<', mutatorName: '<=To<' },
+    { replacement: '>', mutatorName: '<=To>' },
+  ],
+  '>': [
+    { replacement: '>=', mutatorName: '>To>=' },
+    { replacement: '<=', mutatorName: '>To<=' },
+  ],
+  '>=': [
+    { replacement: '>', mutatorName: '>=To>' },
+    { replacement: '<', mutatorName: '>=To<' },
+  ],
+  '==': [{ replacement: '!=', mutatorName: '==To!=' }],
+  '!=': [{ replacement: '==', mutatorName: '!=To==' }],
+  '===': [{ replacement: '!==', mutatorName: '===To!==' }],
+  '!==': [{ replacement: '===', mutatorName: '!==To===' }],
 } as const;
 
 function isEqualityOperator(operator: string): operator is keyof typeof operators {
@@ -21,13 +33,26 @@ function isEqualityOperator(operator: string): operator is keyof typeof operator
 export const equalityOperatorMutator: NodeMutator = {
   name: 'EqualityOperator',
 
-  *mutate(path) {
+  *mutate(path, operations) {
     if (path.isBinaryExpression() && isEqualityOperator(path.node.operator)) {
-      for (const mutableOperator of operators[path.node.operator]) {
+      const allMutations = filterMutationLevel(path.node, operations);
+      // throw new Error(allMutations.toString());
+      for (const mutableOperator of allMutations) {
         const replacement = t.cloneNode(path.node, true);
-        replacement.operator = mutableOperator;
+        replacement.operator = mutableOperator.replacement;
         yield replacement;
       }
     }
   },
 };
+
+function filterMutationLevel(node: types.BinaryExpression, operations: string[] | undefined) {
+  const allMutations = operators[node.operator as keyof typeof operators];
+
+  // Nothing allowed, so return an empty array
+  if (operations === undefined) {
+    return allMutations;
+  }
+
+  return allMutations.filter((mut) => operations.some((op) => op === mut.mutatorName));
+}
diff --git a/packages/instrumenter/test/unit/mutators/arithmatic-operator-mutator.spec.ts b/packages/instrumenter/test/unit/mutators/arithmatic-operator-mutator.spec.ts
@@ -1,7 +1,11 @@
 import { expect } from 'chai';
 
+import { MutationLevel } from '@stryker-mutator/api/core';
+
 import { arithmeticOperatorMutator as sut } from '../../../src/mutators/arithmetic-operator-mutator.js';
-import { expectJSMutation } from '../../helpers/expect-mutation.js';
+import { expectJSMutation, expectJSMutationWithLevel } from '../../helpers/expect-mutation.js';
+
+const arithmeticLevel: MutationLevel = { name: 'ArithemticLevel', ArithmeticOperator: ['+To-', '-To+', '*To/'] };
 
 describe(sut.name, () => {
   it('should have name "ArithmeticOperator"', () => {
@@ -30,4 +34,15 @@ describe(sut.name, () => {
 
     expectJSMutation(sut, '"a" + b + "c" + d + "e"');
   });
+
+  it('should only mutate +, - and * from all possible mutators', () => {
+    expectJSMutationWithLevel(
+      sut,
+      arithmeticLevel.ArithmeticOperator,
+      'a + b; a - b; a * b; a % b; a / b; a % b',
+      'a - b; a - b; a * b; a % b; a / b; a % b', // mutates +
+      'a + b; a + b; a * b; a % b; a / b; a % b', // mutates -
+      'a + b; a - b; a / b; a % b; a / b; a % b', // mutates *
+    );
+  });
 });
diff --git a/packages/instrumenter/test/unit/mutators/equality-operator-mutator.spec.ts b/packages/instrumenter/test/unit/mutators/equality-operator-mutator.spec.ts
@@ -1,7 +1,13 @@
 import { expect } from 'chai';
 
+import { MutationLevel } from '@stryker-mutator/api/core';
+
 import { equalityOperatorMutator as sut } from '../../../src/mutators/equality-operator-mutator.js';
-import { expectJSMutation } from '../../helpers/expect-mutation.js';
+import { expectJSMutation, expectJSMutationWithLevel } from '../../helpers/expect-mutation.js';
+
+const equalityLevelA: MutationLevel = { name: 'EqualityLevelA', EqualityOperator: ['<To<=', '<To>=', '>=To>', '>=To<', '==To!='] };
+
+const equalityLevelB: MutationLevel = { name: 'EqualityLevelB', EqualityOperator: ['<=To>', '>To<=', '===To!=='] };
 
 describe(sut.name, () => {
   it('should have name "EqualityOperator"', () => {
@@ -27,4 +33,28 @@ describe(sut.name, () => {
     expectJSMutation(sut, 'a != b', 'a == b');
     expectJSMutation(sut, 'a !== b', 'a === b');
   });
+
+  it('should only mutate <, >=, == from all possible mutators', () => {
+    expectJSMutationWithLevel(
+      sut,
+      equalityLevelA.EqualityOperator,
+      'a < b; a <= b; a > b; a >= b; a == b; a != b; a === b; a !== b',
+      'a <= b; a <= b; a > b; a >= b; a == b; a != b; a === b; a !== b', // mutates <
+      'a >= b; a <= b; a > b; a >= b; a == b; a != b; a === b; a !== b', // mutates <
+      'a < b; a <= b; a > b; a > b; a == b; a != b; a === b; a !== b', // mutates >=
+      'a < b; a <= b; a > b; a < b; a == b; a != b; a === b; a !== b', // mutates >=
+      'a < b; a <= b; a > b; a >= b; a != b; a != b; a === b; a !== b', // mutates ==
+    );
+  });
+
+  it('should only mutate <= to >, > to <=, and === to !== from all possible mutators', () => {
+    expectJSMutationWithLevel(
+      sut,
+      equalityLevelB.EqualityOperator,
+      'a < b; a <= b; a > b; a >= b; a == b; a != b; a === b; a !== b',
+      'a < b; a > b; a > b; a >= b; a == b; a != b; a === b; a !== b', // mutates <= to >
+      'a < b; a <= b; a <= b; a >= b; a == b; a != b; a === b; a !== b', // mutates > to <=
+      'a < b; a <= b; a > b; a >= b; a == b; a != b; a !== b; a !== b', // mutates === to !==
+    );
+  });
 });
diff --git a/testing-project/stryker.conf.json b/testing-project/stryker.conf.json
@@ -18,6 +18,7 @@
   "mutationLevels": [
     { 
       "name": "default",
+      "ArithmeticOperator": ["+To-", "-To+", "*To/"],
       "ArrayDeclaration": ["EmptyArray", "FilledArray", "FilledArrayConstructor"]
 
     },