[#27] Accept recordDelimiter for csv stringifier

ryu1kn · Jun 18, 2019 · f31beb5 · f31beb5
1 parent 5c12dd7
commit f31beb5
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Showing 10 changed files with 97 additions and 22 deletions.
diff --git a/README.md b/README.md
@@ -138,13 +138,13 @@ console.log(csvStringifier.stringifyRecords(records));
 
       Default: `,`. Only either comma `,` or semicolon `;` is allowed.
 
-  * encoding `<string>` (optional)
+  * recordDelimiter `<string>` (optional)
 
-      Default: `utf8`.
+      Default: `\n`. Only either comma `\n` or semicolon `\r\n` is allowed.
 
-  * newline `<string>` (optional)
+  * encoding `<string>` (optional)
 
-      Default: `lf`. Possible values: `lf`, `crlf`.
+      Default: `utf8`.
 
   * append `<boolean>` (optional)
 
@@ -175,13 +175,13 @@ console.log(csvStringifier.stringifyRecords(records));
 
       Default: `,`. Only either comma `,` or semicolon `;` is allowed.
 
-  * encoding `<string>` (optional)
+  * recordDelimiter `<string>` (optional)
 
-      Default: `utf8`.
+      Default: `\n`. Only either comma `\n` or semicolon `\r\n` is allowed.
 
-  * newline `<string>` (optional)
+  * encoding `<string>` (optional)
 
-      Default: `lf`. Possible values: `lf`, `crlf`.
+      Default: `utf8`.
 
   * append `<boolean>` (optional)
 
@@ -222,6 +222,10 @@ console.log(csvStringifier.stringifyRecords(records));
 
       Default: `,`. Only either comma `,` or semicolon `;` is allowed.
 
+  * recordDelimiter `<string>` (optional)
+
+      Default: `\n`. Only either comma `\n` or semicolon `\r\n` is allowed.
+
 ##### Returns:
 
 * `<ObjectCsvStringifier>`
@@ -255,6 +259,10 @@ console.log(csvStringifier.stringifyRecords(records));
 
       Default: `,`. Only either comma `,` or semicolon `;` is allowed.
 
+  * recordDelimiter `<string>` (optional)
+
+      Default: `\n`. Only either comma `\n` or semicolon `\r\n` is allowed.
+
 ##### Returns:
 
 * `<ArrayCsvStringifier>`

diff --git a/src/lib/csv-stringifier-factory.ts b/src/lib/csv-stringifier-factory.ts
@@ -6,30 +6,39 @@ import {ObjectStringifierHeader} from './record';
 const DEFAULT_FIELD_DELIMITER = ',';
 const VALID_FIELD_DELIMITERS = [DEFAULT_FIELD_DELIMITER, ';'];
 
+const DEFAULT_RECORD_DELIMITER = '\n';
+const VALID_RECORD_DELIMITERS = [DEFAULT_RECORD_DELIMITER, '\r\n'];
+
 export interface ArrayCsvStringifierParams {
     header?: string[];
     fieldDelimiter?: string;
+    recordDelimiter?: string;
 }
 
 export interface ObjectCsvStringifierParams {
     header: ObjectStringifierHeader;
     fieldDelimiter?: string;
+    recordDelimiter?: string;
 }
 
 export class CsvStringifierFactory {
 
     createArrayCsvStringifier(params: ArrayCsvStringifierParams) {
         const fieldDelimiter = params.fieldDelimiter || DEFAULT_FIELD_DELIMITER;
+        const recordDelimiter = params.recordDelimiter || DEFAULT_RECORD_DELIMITER;
         _validateFieldDelimiter(fieldDelimiter);
+        _validateRecordDelimiter(recordDelimiter);
         const fieldStringifier = new FieldStringifier(fieldDelimiter);
-        return new ArrayCsvStringifier(fieldStringifier, fieldDelimiter, params.header);
+        return new ArrayCsvStringifier(fieldStringifier, fieldDelimiter, recordDelimiter, params.header);
     }
 
     createObjectCsvStringifier(params: ObjectCsvStringifierParams) {
         const fieldDelimiter = params.fieldDelimiter || DEFAULT_FIELD_DELIMITER;
+        const recordDelimiter = params.recordDelimiter || DEFAULT_RECORD_DELIMITER;
         _validateFieldDelimiter(fieldDelimiter);
+        _validateRecordDelimiter(recordDelimiter);
         const fieldStringifier = new FieldStringifier(fieldDelimiter);
-        return new ObjectCsvStringifier(fieldStringifier, fieldDelimiter, params.header);
+        return new ObjectCsvStringifier(fieldStringifier, fieldDelimiter, recordDelimiter, params.header);
     }
 
 }
@@ -39,3 +48,9 @@ function _validateFieldDelimiter(delimiter: string): void {
         throw new Error(`Invalid field delimiter \`${delimiter}\` is specified`);
     }
 }
+
+function _validateRecordDelimiter(delimiter: string): void {
+    if (VALID_RECORD_DELIMITERS.indexOf(delimiter) === -1) {
+        throw new Error(`Invalid record delimiter \`${delimiter}\` is specified`);
+    }
+}
diff --git a/src/lib/csv-stringifiers/abstract.ts b/src/lib/csv-stringifiers/abstract.ts
@@ -1,15 +1,15 @@
 import {FieldStringifier} from '../field-stringifier';
 import {Field} from '../record';
 
-const RECORD_DELIMITER = '\n';
-
 export abstract class CsvStringifier<T> {
     private readonly fieldStringifier: FieldStringifier;
     private readonly fieldDelimiter: string;
+    private readonly recordDelimiter: string;
 
-    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string) {
+    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string, recordDelimiter: string) {
         this.fieldStringifier = fieldStringifier;
         this.fieldDelimiter = fieldDelimiter;
+        this.recordDelimiter = recordDelimiter;
     }
 
     getHeaderString(): string | null {
@@ -19,7 +19,7 @@ export abstract class CsvStringifier<T> {
 
     stringifyRecords(records: IterableIterator<T> | T[]): string {
         const csvLines = Array.from(records, record => this.getCsvLine(this.getRecordAsArray(record)));
-        return csvLines.join(RECORD_DELIMITER) + RECORD_DELIMITER;
+        return csvLines.join(this.recordDelimiter) + this.recordDelimiter;
     }
 
     protected abstract getRecordAsArray(_record: T): Field[];

diff --git a/src/lib/csv-stringifiers/array.ts b/src/lib/csv-stringifiers/array.ts
@@ -5,8 +5,8 @@ import {Field} from '../record';
 export class ArrayCsvStringifier extends CsvStringifier<Field[]> {
     private readonly header?: string[];
 
-    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string, header?: string[]) {
-        super(fieldStringifier, fieldDelimiter);
+    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string, recordDelimiter: string, header?: string[]) {
+        super(fieldStringifier, fieldDelimiter, recordDelimiter);
         this.header = header;
     }
 

diff --git a/src/lib/csv-stringifiers/object.ts b/src/lib/csv-stringifiers/object.ts
@@ -6,8 +6,8 @@ import {ObjectMap} from '../lang';
 export class ObjectCsvStringifier extends CsvStringifier<ObjectMap<Field>> {
     private readonly header: ObjectStringifierHeader;
 
-    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string, header: ObjectStringifierHeader) {
-        super(fieldStringifier, fieldDelimiter);
+    constructor(fieldStringifier: FieldStringifier, fieldDelimiter: string, recordDelimiter: string, header: ObjectStringifierHeader) {
+        super(fieldStringifier, fieldDelimiter, recordDelimiter);
         this.header = header;
     }
 

diff --git a/src/lib/csv-writer-factory.ts b/src/lib/csv-writer-factory.ts
@@ -6,6 +6,7 @@ export interface ArrayCsvWriterParams {
     path: string;
     header?: string[];
     fieldDelimiter?: string;
+    recordDelimiter?: string;
     encoding?: string;
     append?: boolean;
 }
@@ -14,6 +15,7 @@ export interface ObjectCsvWriterParams {
     path: string;
     header: ObjectStringifierHeader;
     fieldDelimiter?: string;
+    recordDelimiter?: string;
     encoding?: string;
     append?: boolean;
 }
@@ -28,15 +30,17 @@ export class CsvWriterFactory {
     createArrayCsvWriter(params: ArrayCsvWriterParams) {
         const csvStringifier = this.csvStringifierFactory.createArrayCsvStringifier({
             header: params.header,
-            fieldDelimiter: params.fieldDelimiter
+            fieldDelimiter: params.fieldDelimiter,
+            recordDelimiter: params.recordDelimiter
         });
         return new CsvWriter(csvStringifier, params.path, params.encoding, params.append);
     }
 
     createObjectCsvWriter(params: ObjectCsvWriterParams) {
         const csvStringifier = this.csvStringifierFactory.createObjectCsvStringifier({
             header: params.header,
-            fieldDelimiter: params.fieldDelimiter
+            fieldDelimiter: params.fieldDelimiter,
+            recordDelimiter: params.recordDelimiter
         });
         return new CsvWriter(csvStringifier, params.path, params.encoding, params.append);
     }

diff --git a/src/test/csv-stringifiers/array.test.ts b/src/test/csv-stringifiers/array.test.ts
@@ -20,6 +20,14 @@ describe('ArrayCsvStringifier', () => {
         });
     });
 
+    describe('When record delimiter is neither LF nor CR+LF', () => {
+        it('throws an exception', () => {
+            assert.throws(() => {
+                createArrayCsvStringifier({recordDelimiter: '\r'});
+            });
+        });
+    });
+
     describe('When records input is an iterable other than an array', () => {
         const stringifier = createArrayCsvStringifier({
             header: ['TITLE_A', 'TITLE_B']

diff --git a/src/test/csv-stringifiers/object.test.ts b/src/test/csv-stringifiers/object.test.ts
@@ -23,6 +23,17 @@ describe('ObjectCsvStringifier', () => {
         });
     });
 
+    describe('When record delimiter is neither LF nor CR+LF', () => {
+        it('throws an exception', () => {
+            assert.throws(() => {
+                createObjectCsvStringifier({
+                    header: ['FIELD_A', 'FIELD_B'],
+                    recordDelimiter: '\r'
+                });
+            });
+        });
+    });
+
     describe('When records input is an iterable other than an array', () => {
         const stringifier = createObjectCsvStringifier({
             header: ['FIELD_A', 'FIELD_B']

diff --git a/src/test/write-array-records.test.ts b/src/test/write-array-records.test.ts
@@ -96,10 +96,24 @@ describe('Write array records into CSV', () => {
             fieldDelimiter: ';'
         });
 
-        it('writes to a file with the specified encoding', () => {
+        it('uses semicolon instead of comma to separate fields', () => {
             return writer.writeRecords(records).then(() => {
                 assertFile(filePath, 'NAME;LANGUAGE\nBob;French\nMary;English\n');
             });
         });
     });
+
+    describe('When newline is specified', () => {
+        const filePath = makeFilePath('newline');
+        const writer = createArrayCsvWriter({
+            path: filePath,
+            recordDelimiter: '\r\n'
+        });
+
+        it('writes to a file with the specified newline character', () => {
+            return writer.writeRecords(records).then(() => {
+                assertFile(filePath, 'Bob,French\r\nMary,English\r\n');
+            });
+        });
+    });
 });
diff --git a/src/test/write-object-records.test.ts b/src/test/write-object-records.test.ts
@@ -115,10 +115,25 @@ describe('Write object records into CSV', () => {
             fieldDelimiter: ';'
         });
 
-        it('writes to a file with the specified encoding', () => {
+        it('uses semicolon instead of comma to separate fields', () => {
             return writer.writeRecords(records).then(() => {
                 assertFile(filePath, 'NAME;LANGUAGE\nBob;French\nMary;English\n');
             });
         });
     });
+
+    describe('When newline is specified', () => {
+        const filePath = makeFilePath('newline');
+        const writer = createObjectCsvWriter({
+            path: filePath,
+            header: ['name', 'lang'],
+            recordDelimiter: '\r\n'
+        });
+
+        it('writes to a file with the specified newline character', () => {
+            return writer.writeRecords(records).then(() => {
+                assertFile(filePath, 'Bob,French\r\nMary,English\r\n');
+            });
+        });
+    });
 });