Add YAML module

.gitignore

@@ -4,4 +4,5 @@ deno.d.ts
 node_modules
 package.json
 package-lock.json
+yarn.lock
 .vscode

README.md

@@ -35,6 +35,7 @@ Here are the dedicated documentations of modules:
 - [strings](strings/README.md)
 - [testing](testing/README.md)
 - [ws](ws/README.md)
+- [yaml](yaml/README.md)
 
 ## Contributing
 

encoding/README.md

@@ -217,3 +217,21 @@ const obj = {
 };
 const tomlString = stringify(obj);
 ```
+
+## YAML
+
+YAML parser / dumper for Deno
+
+Heavily inspired from [js-yaml]
+
+### Example
+See [`./yaml/example`](./yaml/example) folder and [js-yaml] repository.
+
+### :warning: Limitations
+- `binary` type is currently not stable
+- `function`, `regexp`, and `undefined` type are currently not supported
+
+# Basic usage
+TBD
+
+[js-yaml]: https://github.com/nodeca/js-yaml

encoding/test.ts

@@ -2,3 +2,4 @@
 import "./hex_test.ts";
 import "./toml_test.ts";
 import "./csv_test.ts";
+import "./yaml_test.ts";

encoding/yaml.ts

@@ -0,0 +1,7 @@
+// Ported from js-yaml:
+// https://github.com/nodeca/js-yaml/
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+export * from "./yaml/parse.ts";
+export * from "./yaml/stringify.ts";
+export * from "./yaml/schema/mod.ts";

encoding/yaml/Mark.ts

@@ -0,0 +1,72 @@
+import { repeat } from "./utils.ts";
+
+export class Mark {
+  constructor(
+    public name: string,
+    public buffer: string,
+    public position: number,
+    public line: number,
+    public column: number
+  ) {}
+
+  public getSnippet(indent = 4, maxLength = 75) {
+    if (!this.buffer) return null;
+
+    let head = "";
+    let start = this.position;
+
+    while (
+      start > 0 &&
+      "\x00\r\n\x85\u2028\u2029".indexOf(this.buffer.charAt(start - 1)) === -1
+    ) {
+      start -= 1;
+      if (this.position - start > maxLength / 2 - 1) {
+        head = " ... ";
+        start += 5;
+        break;
+      }
+    }
+
+    let tail = "";
+    let end = this.position;
+
+    while (
+      end < this.buffer.length &&
+      "\x00\r\n\x85\u2028\u2029".indexOf(this.buffer.charAt(end)) === -1
+    ) {
+      end += 1;
+      if (end - this.position > maxLength / 2 - 1) {
+        tail = " ... ";
+        end -= 5;
+        break;
+      }
+    }
+
+    const snippet = this.buffer.slice(start, end);
+    return `${repeat(" ", indent)}${head}${snippet}${tail}\n${repeat(
+      " ",
+      indent + this.position - start + head.length
+    )}^`;
+  }
+
+  public toString(compact?: boolean) {
+    let snippet,
+      where = "";
+
+    if (this.name) {
+      where += `in "${this.name}" `;
+    }
+
+    where += `at line ${this.line + 1}, column ${this.column + 1}`;
+
+    if (!compact) {
+      snippet = this.getSnippet();
+
+      if (snippet) {
+        where += `:\n${snippet}`;
+      }
+    }
+
+    return where;
+  }
+}

encoding/yaml/Schema.ts

@@ -0,0 +1,95 @@
+import { YAMLError } from "./error/YAMLError.ts";
+import { KindType, Type } from "./Type.ts";
+import { ArrayObject } from "./utils.ts";
+
+function compileList(
+  schema: Schema,
+  name: "implicit" | "explicit",
+  result: Type[]
+): Type[] {
+  const exclude: number[] = [];
+
+  for (const includedSchema of schema.include) {
+    result = compileList(includedSchema, name, result);
+  }
+
+  for (const currentType of schema[name]) {
+    for (
+      let previousIndex = 0;
+      previousIndex < result.length;
+      previousIndex++
+    ) {
+      const previousType = result[previousIndex];
+      if (
+        previousType.tag === currentType.tag &&
+        previousType.kind === currentType.kind
+      ) {
+        exclude.push(previousIndex);
+      }
+    }
+
+    result.push(currentType);
+  }
+
+  return result.filter((type, index) => !exclude.includes(index));
+}
+
+export type TypeMap = { [k in KindType | "fallback"]: ArrayObject<Type> };
+function compileMap(...typesList: Type[][]) {
+  const result: TypeMap = {
+    fallback: {},
+    mapping: {},
+    scalar: {},
+    sequence: {}
+  };
+
+  for (const types of typesList) {
+    for (const type of types) {
+      if (type.kind !== null) {
+        result[type.kind][type.tag] = result["fallback"][type.tag] = type;
+      }
+    }
+  }
+  return result;
+}
+
+export class Schema implements SchemaDefinition {
+  public static SCHEMA_DEFAULT?: Schema;
+
+  public implicit: Type[];
+  public explicit: Type[];
+  public include: Schema[];
+
+  public compiledImplicit: Type[];
+  public compiledExplicit: Type[];
+  public compiledTypeMap: TypeMap;
+
+  constructor(definition: SchemaDefinition) {
+    this.explicit = definition.explicit || [];
+    this.implicit = definition.implicit || [];
+    this.include = definition.include || [];
+
+    for (const type of this.implicit) {
+      if (type.loadKind && type.loadKind !== "scalar") {
+        throw new YAMLError(
+          "There is a non-scalar type in the implicit list of a schema. Implicit resolving of such types is not supported."
+        );
+      }
+    }
+
+    this.compiledImplicit = compileList(this, "implicit", []);
+    this.compiledExplicit = compileList(this, "explicit", []);
+    this.compiledTypeMap = compileMap(
+      this.compiledImplicit,
+      this.compiledExplicit
+    );
+  }
+
+  public static create() {}
+}
+
+export interface SchemaDefinition {
+  implicit?: any[];
+  explicit?: Type[];
+  include?: Schema[];
+}

encoding/yaml/State.ts

@@ -0,0 +1,6 @@
+import { SchemaDefinition } from "./Schema.ts";
+import { DEFAULT_FULL_SCHEMA } from "./schema/mod.ts";
+
+export abstract class State {
+  constructor(public schema: SchemaDefinition = DEFAULT_FULL_SCHEMA) {}
+}

encoding/yaml/Type.ts

@@ -0,0 +1,50 @@
+import { ArrayObject } from "./utils.ts";
+
+export type KindType = "sequence" | "scalar" | "mapping";
+export type StyleVariant = "lowercase" | "uppercase" | "camelcase" | "decimal";
+export type RepresentFn = (data: any, style?: StyleVariant) => any;
+
+const DEFAULT_RESOLVE = () => true;
+const DEFAULT_CONSTRUCT = (data: any) => data;
+
+interface TypeOptions {
+  kind: KindType;
+  resolve?: (data: any) => boolean;
+  construct?: (data: string) => any;
+  instanceOf?: any;
+  predicate?: (data: object) => boolean;
+  represent?: RepresentFn | ArrayObject<RepresentFn>;
+  defaultStyle?: StyleVariant;
+  styleAliases?: { [x: string]: any };
+}
+
+function checkTagFormat(tag: string): string {
+  return tag;
+}
+
+export class Type {
+  public tag: string;
+  public kind: KindType | null = null;
+  public instanceOf: any;
+  public predicate?: (data: object) => boolean;
+  public represent?: RepresentFn | ArrayObject<RepresentFn>;
+  public defaultStyle?: StyleVariant;
+  public styleAliases?: { [x: string]: any };
+  public loadKind?: KindType;
+
+  constructor(tag: string, options?: TypeOptions) {
+    this.tag = checkTagFormat(tag);
+    if (options) {
+      this.kind = options.kind;
+      this.resolve = options.resolve || DEFAULT_RESOLVE;
+      this.construct = options.construct || DEFAULT_CONSTRUCT;
+      this.instanceOf = options.instanceOf;
+      this.predicate = options.predicate;
+      this.represent = options.represent;
+      this.defaultStyle = options.defaultStyle;
+      this.styleAliases = options.styleAliases;
+    }
+  }
+  public resolve: (data?: any) => boolean = () => true;
+  public construct: (data?: any) => any = data => data;
+}

encoding/yaml/devDeps.ts

@@ -0,0 +1,3 @@
+import * as asserts from "../testing/asserts.ts";
+import * as testing from "../testing/mod.ts";
+export { testing, asserts };

encoding/yaml/dumper/DumperState.ts

@@ -0,0 +1,111 @@
+import { Schema, SchemaDefinition } from "../Schema.ts";
+import { State } from "../State.ts";
+import { StyleVariant, Type } from "../Type.ts";
+import { ArrayObject } from "../utils.ts";
+
+const _hasOwnProperty = Object.prototype.hasOwnProperty;
+
+function compileStyleMap(
+  schema: Schema,
+  map?: ArrayObject<StyleVariant> | null
+): ArrayObject<StyleVariant> {
+  if (typeof map === "undefined" || map === null) return {};
+
+  let type: Type;
+  const result: ArrayObject<StyleVariant> = {};
+  const keys = Object.keys(map);
+  let tag: string, style: StyleVariant;
+  for (let index = 0, length = keys.length; index < length; index += 1) {
+    tag = keys[index];
+    style = String(map[tag]) as StyleVariant;
+    if (tag.slice(0, 2) === "!!") {
+      tag = `tag:yaml.org,2002:${tag.slice(2)}`;
+    }
+    type = schema.compiledTypeMap.fallback[tag];
+
+    if (type && _hasOwnProperty.call(type.styleAliases, style)) {
+      style = type.styleAliases[style];
+    }
+
+    result[tag] = style;
+  }
+
+  return result;
+}
+
+export interface DumperStateOptions {
+  /** 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?: ArrayObject<StyleVariant> | null;
+  /** specifies a schema to use. */
+  schema?: SchemaDefinition;
+  /** if true, sort keys when dumping YAML. If a function, use the function to sort the keys. (default: false) */
+  sortKeys?: boolean | ((a: any, b: any) => number);
+  /** set max line width. (default: 80) */
+  lineWidth?: number;
+  /** if true, don't convert duplicate objects into references (default: false) */
+  noRefs?: boolean;
+  /** if true don't try to be compatible with older yaml versions. Currently: don't quote "yes", "no" and so on, as required for YAML 1.1 (default: false) */
+  noCompatMode?: boolean;
+  /**
+   * if true flow sequences will be condensed, omitting the space between `key: value` or `a, b`. Eg. `'[a,b]'` or `{a:{b:c}}`.
+   * Can be useful when using yaml for pretty URL query params as spaces are %-encoded. (default: false).
+   */
+  condenseFlow?: boolean;
+}
+
+export class DumperState extends State {
+  public indent: number;
+  public noArrayIndent: boolean;
+  public skipInvalid: boolean;
+  public flowLevel: number;
+  public sortKeys: boolean | ((a: any, b: any) => number);
+  public lineWidth: number;
+  public noRefs: boolean;
+  public noCompatMode: boolean;
+  public condenseFlow: boolean;
+  public implicitTypes: Type[];
+  public explicitTypes: Type[];
+  public tag: string | null = null;
+  public result: string = "";
+  public duplicates = [];
+  public usedDuplicates = null;
+  public styleMap: ArrayObject<StyleVariant>;
+  public dump: any;
+
+  constructor({
+    schema,
+    indent = 2,
+    noArrayIndent = false,
+    skipInvalid = false,
+    flowLevel = -1,
+    styles = null,
+    sortKeys = false,
+    lineWidth = 80,
+    noRefs = false,
+    noCompatMode = false,
+    condenseFlow = false
+  }: DumperStateOptions) {
+    super(schema);
+    this.indent = Math.max(1, indent);
+    this.noArrayIndent = noArrayIndent;
+    this.skipInvalid = skipInvalid;
+    this.flowLevel = flowLevel;
+    this.styleMap = compileStyleMap(this.schema as Schema, styles);
+    this.sortKeys = sortKeys;
+    this.lineWidth = lineWidth;
+    this.noRefs = noRefs;
+    this.noCompatMode = noCompatMode;
+    this.condenseFlow = condenseFlow;
+
+    this.implicitTypes = (this.schema as Schema).compiledImplicit;
+    this.explicitTypes = (this.schema as Schema).compiledExplicit;
+  }
+}