refactor!: next() should return Buffer | null

nacholibre#40

src/index.ts

@@ -177,12 +177,12 @@ export class LineByLine {
     }
 
     /**
-     * Returns buffer with the line data without the `newLineCharacter` or `false` if end of file is reached.
+     * Returns buffer with the line data without the `newLineCharacter` or `null` if end of file is reached.
      */
-    next() {
-        if (this.fd === null) return false;
+    next(): Buffer | null {
+        if (this.fd === null) return null as null;
 
-        let line: Buffer = false as any;
+        let line: Buffer = null as null;
 
         if (this.eofReached && this.linesCache.length === 0) {
             this.close();

test/readlines.test.ts

@@ -9,8 +9,8 @@ test('should get all lines', () => {
 
     expect(liner.next().toString('ascii')).toBe('hello');
     expect(liner.next().toString('ascii')).toBe('hello2');
-    expect(liner.next()).toBe(false);
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -19,22 +19,22 @@ test('should get all lines even if the file doesnt end with new line', () => {
 
     expect(liner.next().toString('ascii')).toBe('google.com');
     expect(liner.next().toString('ascii')).toBe('yahoo.com');
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
 test('should get all lines if there is no new lines', () => {
     const liner = new lineByLine(resolve(__dirname, 'fixtures/noNewLinesFile.txt'));
 
     expect(liner.next().toString('ascii')).toBe('no new line');
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
 test('should handle empty files', () => {
     const liner = new lineByLine(resolve(__dirname, 'fixtures/emptyFile.txt'));
 
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -46,7 +46,7 @@ test('should read right between two chunks', () => {
     expect(liner.next().toString('ascii')).toBe('google.com');
     expect(liner.next().toString('ascii')).toBe('yahoo.com');
     expect(liner.next().toString('ascii')).toBe('yandex.ru');
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -58,7 +58,7 @@ test('should read empty lines', () => {
     expect(liner.next().toString('ascii')).toBe('');
     expect(liner.next().toString('ascii')).toBe('hello2');
     expect(liner.next().toString('ascii')).toBe('hello3');
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -75,7 +75,7 @@ test('should reset and start from the beginning', () => {
     expect(liner.next().toString('ascii')).toBe('google.com');
     expect(liner.next().toString('ascii')).toBe('yahoo.com');
     expect(liner.next().toString('ascii')).toBe('yandex.ru');
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -94,7 +94,7 @@ test('should read big lines', () => {
     expect(JSON.parse(liner.next() as any)).toMatchObject(expected);
     expect(JSON.parse(liner.next() as any)).toMatchObject(expected);
 
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 });
 
@@ -114,7 +114,7 @@ test('Manually Close', () => {
     liner.close();
     expect(liner.fd).toBe(null);
 
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
 });
 
 test('should correctly processes NULL character in lines', () => {
@@ -124,6 +124,6 @@ test('should correctly processes NULL character in lines', () => {
     expect(liner.next().toString()).toBe('line wi'+String.fromCharCode(0)+'th null');
     expect(liner.next().toString()).toBe('another line without null');
 
-    expect(liner.next()).toBe(false);
+    expect(liner.next()).toBe(null);
     expect(liner.fd).toBe(null);
 })