Support lineWidth dump option

src/dumper.ts

@@ -1,6 +1,9 @@
 
 
 'use strict';
+
+import { SchemaDefinition } from "./schema";
+
 declare function require(n:string):any
 /*eslint-disable no-use-before-define*/
 
@@ -110,9 +113,10 @@ function encodeHex(character) {
   return '\\' + handle + common.repeat('0', length - string.length) + string;
 }
 
-function State(options) {
+function State(options: DumpOptions) {
   this.schema      = options['schema'] || DEFAULT_FULL_SCHEMA;
   this.indent      = Math.max(1, (options['indent'] || 2));
+  this.lineWidth   = options.lineWidth !== void 0 ? options.lineWidth : 80;
   this.skipInvalid = options['skipInvalid'] || false;
   this.flowLevel   = (common.isNothing(options['flowLevel']) ? -1 : options['flowLevel']);
   this.styleMap    = compileStyleMap(this.schema, options['styles'] || null);
@@ -264,11 +268,13 @@ function writeScalar(state, object, level) {
   longestLine = 0;
 
   indent = state.indent * level;
-  max = 80;
-  if (indent < 40) {
-    max -= indent;
-  } else {
-    max = 40;
+  max = state.lineWidth;
+  if (isFinite(max)) {
+    if (indent < 40) {
+      max -= indent;
+    } else {
+      max = 40;
+    }
   }
 
   for (position = 0; position < object.length; position++) {
@@ -431,6 +437,10 @@ function foldLine(line, max) {
     return line;
   }
 
+  if (!isFinite(max)) {
+    return line;
+  }
+
   var foldRe = /[^\s] [^\s]/g,
       result = '',
       prevMatch = 0,
@@ -817,7 +827,24 @@ function inspectNode(object, objects, duplicatesIndexes) {
   }
 }
 
-export function dump(input, options) {
+export interface DumpOptions {
+  /** indentation width to use (in spaces). */
+  indent?: number;
+  /** when true, will not add an indentation level to array elements */
+  noArrayIndent?: boolean;
+  /** do not throw on invalid types (like function in the safe schema) and skip pairs and single values with such types. */
+  skipInvalid?: boolean;
+  /** specifies level of nesting, when to switch from block to flow style for collections. -1 means block style everwhere */
+  flowLevel?: number;
+  /** Each tag may have own set of styles.	- "tag" => "style" map. */
+  styles?: { [x: string]: any; };
+  /** specifies a schema to use. */
+  schema?: SchemaDefinition;
+  /** set max line width. (default: 80) */
+  lineWidth?: number;
+}
+
+export function dump(input, options?: DumpOptions) {
   options = options || {};
 
   var state = new State(options);
@@ -830,6 +857,6 @@ export function dump(input, options) {
   return '';
 }
 
-export function safeDump(input, options) {
+export function safeDump(input, options?: DumpOptions) {
   return dump(input, common.extend({ schema: DEFAULT_SAFE_SCHEMA }, options));
 }

src/index.ts

@@ -4,7 +4,7 @@
  */
 
 export {load, loadAll, safeLoad, safeLoadAll, LoadOptions} from './loader';
-export {dump, safeDump} from './dumper';
+export {dump, safeDump, DumpOptions} from './dumper';
 
 import Mark=require("./mark")
 export import YAMLException = require('./exception');

test/dumper.test.ts

@@ -0,0 +1,30 @@
+import * as chai from 'chai';
+import { safeDump } from '../src';
+const expect = chai.expect;
+
+suite('Dumper', () => {
+  suite('lineWidth dump option', () => {
+    test('should respect lineWidth for multi-line strings', () => {
+      const description = `Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae
+Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et.`;
+
+      expect(safeDump({ description }, { lineWidth: 100 })).to.equal(`description: >-
+  Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium,
+  totam rem aperiam, eaque ipsa quae
+
+  Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed
+  quia non numquam eius modi tempora incidunt ut labore et.
+`);
+    });
+
+    test('should use literal block-scalar style if lineWidth is Infinity (or very lengthy)', () => {
+      const description = `Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae
+Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et.`;
+
+      expect(safeDump({ description }, { lineWidth: Infinity })).to.equal(`description: |-
+  Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae
+  Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et.
+`);
+    });
+  });
+});