feat(detector): detect test cases

Author: marabesi

detector/src/smells-detector.ts

@@ -1,5 +1,5 @@
 import { parseScript } from 'esprima';
-import { createSourceFile, ScriptTarget } from 'typescript';
+import * as ts from 'typescript';
 import { JavascriptSmells } from './languages/JavascriptSmells';
 import { TypescriptSmells } from './languages/TypescriptSmells';
 import { SmellDetectorRunnerResult, SupportedLanguages } from './types';
@@ -17,7 +17,42 @@ export class SmellDetector {
     }
 
     // wondering why createSource? https://stackoverflow.com/a/60462133/2258921
-    const ast = createSourceFile('temp.ts', this.code, ScriptTarget.ES2020, true);
-    return { smells: new TypescriptSmells(ast).searchSmells(), testCases: [] };
+    const ast = ts.createSourceFile('temp.ts', this.code, ts.ScriptTarget.ES2020, true);
+
+    const testCases = findItCalls(ast).map(({ lineStart, columnStart, lineEnd, columnEnd }) => ({
+      lineStart,
+      startAt: columnStart,
+      lineEnd,
+      endsAt: columnEnd,
+    }));
+
+    return { smells: new TypescriptSmells(ast).searchSmells(), testCases };
+  }
+}
+
+function findItCalls(sourceFile: ts.SourceFile): { lineStart: number, columnStart: number, lineEnd: number, columnEnd: number }[] {
+  const itCalls: { lineStart: number, columnStart: number, lineEnd: number, columnEnd: number }[] = [];
+
+  function traverse(node: ts.Node) {
+    if (ts.isCallExpression(node)) {
+      const expression = node.expression;
+      const isItCall = ts.isIdentifier(expression) && expression.text === 'it';
+      const isTestCall = ts.isIdentifier(expression) && expression.text === 'test';
+      if (isItCall || isTestCall) {
+        const { line, character } = sourceFile.getLineAndCharacterOfPosition(node.getStart());
+        const { line: lineEnd, character: columnEnd } = sourceFile.getLineAndCharacterOfPosition(node.getEnd());
+        itCalls.push({
+          lineStart: line + 1,
+          columnStart: character,
+          lineEnd: lineEnd + 1,
+          columnEnd, 
+        });
+      }
+    }
+
+    ts.forEachChild(node, traverse);
   }
+
+  traverse(sourceFile);
+  return itCalls;
 }

detector/test/smells-detector-with-smells.test.ts

@@ -419,4 +419,85 @@ jest.mock("../");`,
       expect(result[index].diagnostic).toEqual(diagnostic);
     });
   });
+
+  test('should identify the test cases that exists in the file', () => {
+    const code = 'it("a", () => {});';
+    const smellDetector = new SmellDetector(code, TYPESCRIPT);
+    const result = smellDetector.findAll().testCases;
+
+    expect(result).toHaveLength(1);
+  });
+
+   describe.each([
+   [{
+      index: 0,
+     code: `it("a", () => {
+});`,
+     language: TYPESCRIPT,
+     testCases: [{
+       lineStart: 1,
+       lineEnd: 2,
+       startAt: 0,
+       endsAt: 2,
+     }]
+   }],
+   [{
+      index: 0,
+     code: `test("a", () => {
+});`,
+     language: TYPESCRIPT,
+     testCases: [{
+       lineStart: 1,
+       lineEnd: 2,
+       startAt: 0,
+       endsAt: 2,
+     }]
+   }],
+   [{
+      index: 1,
+     code: `test("a", () => {
+});
+test("b", () => {});`,
+     language: TYPESCRIPT,
+     testCases: [{
+       lineStart: 1,
+       lineEnd: 2,
+       startAt: 0,
+       endsAt: 2,
+     }, {
+       lineStart: 3,
+       lineEnd: 3,
+       startAt: 0,
+       endsAt: 19,
+     }]
+   }],
+   ])('testCases', ({ index, code, language, testCases }) => {
+    test(`should line start for test case at index ${index}`, () => {
+      const smellDetector = new SmellDetector(code, language);
+      const result = smellDetector.findAll().testCases;
+ 
+      expect(result[index].lineStart).toEqual(testCases[index].lineStart);
+    });
+
+    test(`should  column start for test case at index ${index}`, () => {
+      const smellDetector = new SmellDetector(code, language);
+      const result = smellDetector.findAll().testCases;
+ 
+      expect(result[index].startAt).toEqual(testCases[index].startAt);
+    });
+    
+    test(`should line end for test case at index ${index}`, () => {
+      const smellDetector = new SmellDetector(code, language);
+      const result = smellDetector.findAll().testCases;
+ 
+      expect(result[index].lineEnd).toEqual(testCases[index].lineEnd);
+    });
+
+    test(`should  column end for test case at index ${index}`, () => {
+      const smellDetector = new SmellDetector(code, language);
+      const result = smellDetector.findAll().testCases;
+ 
+      expect(result[index].endsAt).toEqual(testCases[index].endsAt);
+    });
+   });
 });