fix mutation of Array constructor call for TypeScript

resolves stryker-mutator#1902
brodycj · Nov 29, 2019 · 3b4f9e5 · 3b4f9e5
1 parent fb063cc
commit 3b4f9e5
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Showing 2 changed files with 14 additions and 6 deletions.
diff --git a/packages/mutator-specification/src/ArrayDeclarationMutatorSpec.ts b/packages/mutator-specification/src/ArrayDeclarationMutatorSpec.ts
@@ -20,7 +20,6 @@ export default function ArrayDeclarationMutatorSpec(name: string, expectMutation
     it('should mutate filled Array constructor calls as empty arrays', () => {
       expectMutation('new Array(a, 1 + 1)', 'new Array()');
       expectMutation("new Array('val')", 'new Array()');
-      // XXX known issue on TypeScript mutator:
       expectMutation("Array('val')", 'Array()');
       expectMutation('Array(a, 1 + 1)', 'Array()');
     });
@@ -32,7 +31,6 @@ export default function ArrayDeclarationMutatorSpec(name: string, expectMutation
 
     it('should mutate empty array constructor call as a filled array', () => {
       expectMutation('new Array()', 'new Array([])');
-      // XXX known issue on TypeScript mutator:
       expectMutation('Array()', 'Array([])');
     });
   });

diff --git a/packages/typescript/src/mutator/ArrayDeclarationMutator.ts b/packages/typescript/src/mutator/ArrayDeclarationMutator.ts
@@ -2,20 +2,30 @@ import * as ts from 'typescript';
 
 import NodeMutator, { NodeReplacement } from './NodeMutator';
 
-export default class ArrayDeclarationMutator extends NodeMutator<ts.ArrayLiteralExpression | ts.NewExpression> {
+export default class ArrayDeclarationMutator extends NodeMutator<ts.ArrayLiteralExpression | ts.CallExpression | ts.NewExpression> {
   public name = 'ArrayDeclaration';
 
-  public guard(node: ts.Node): node is ts.ArrayLiteralExpression | ts.NewExpression {
-    return node.kind === ts.SyntaxKind.ArrayLiteralExpression || node.kind === ts.SyntaxKind.NewExpression;
+  public guard(node: ts.Node): node is ts.ArrayLiteralExpression | ts.CallExpression | ts.NewExpression {
+    return node.kind === ts.SyntaxKind.ArrayLiteralExpression || node.kind === ts.SyntaxKind.CallExpression || node.kind === ts.SyntaxKind.NewExpression;
   }
 
-  protected identifyReplacements(node: ts.ArrayLiteralExpression | ts.NewExpression, sourceFile: ts.SourceFile): NodeReplacement[] {
+  protected identifyReplacements(node: ts.ArrayLiteralExpression | ts.CallExpression | ts.NewExpression, sourceFile: ts.SourceFile): NodeReplacement[] {
     if (node.kind === ts.SyntaxKind.ArrayLiteralExpression) {
       if (node.elements.length) {
         return [{ node, replacement: '[]' }];
       } else {
         return [{ node, replacement: '["Stryker was here"]' }];
       }
+    } else if (node.kind === ts.SyntaxKind.CallExpression) {
+      if (node.expression.kind === ts.SyntaxKind.Identifier && node.expression.getFullText(sourceFile).trim() === 'Array') {
+        if (node.arguments && node.arguments.length) {
+          return [{ node, replacement: 'Array()' }];
+        } else {
+          return [{ node, replacement: 'Array([])' }];
+        }
+      } else {
+        return [];
+      }
     } else {
       if (node.expression.getFullText(sourceFile).trim() === 'Array') {
         if (node.arguments && node.arguments.length) {