Add Yaml Source Editor Extension

Changelog: added

app/assets/javascripts/editor/extensions/source_editor_extension_base.js

@@ -36,12 +36,24 @@ export class SourceEditorExtension {
     });
   }
 
-  static highlightLines(instance) {
-    const { hash } = window.location;
-    if (!hash) {
-      return;
+  static removeHighlights(instance) {
+    Object.assign(instance, {
+      lineDecorations: instance.deltaDecorations(instance.lineDecorations || [], []),
+    });
   }
-    const [start, end] = hash.replace(hashRegexp, '').split('-');
+
+  /**
+   * Returns a function that can only be invoked once between
+   * each browser screen repaint.
+   * @param {Object} instance - The Source Editor instance
+   * @param {Array} bounds - The [start, end] array with start
+   * and end coordinates for highlighting
+   */
+  static highlightLines(instance, bounds = null) {
+    const [start, end] =
+      bounds && Array.isArray(bounds)
+        ? bounds
+        : window.location.hash?.replace(hashRegexp, '').split('-');
     let startLine = start ? parseInt(start, 10) : null;
     let endLine = end ? parseInt(end, 10) : startLine;
     if (endLine < startLine) {
@@ -51,15 +63,12 @@ export class SourceEditorExtension {
       window.requestAnimationFrame(() => {
         instance.revealLineInCenter(startLine);
         Object.assign(instance, {
-          lineDecorations: instance.deltaDecorations(
-            [],
-            [
+          lineDecorations: instance.deltaDecorations(instance.lineDecorations || [], [
             {
               range: new Range(startLine, 1, endLine, 1),
               options: { isWholeLine: true, className: 'active-line-text' },
             },
-            ],
-          ),
+          ]),
         });
       });
     }

app/assets/javascripts/editor/extensions/source_editor_yaml_ext.js

+import { toPath } from 'lodash';
+import { parseDocument, Document, visit, isScalar, isCollection, isMap } from 'yaml';
+import { findPair } from 'yaml/util';
+import { SourceEditorExtension } from '~/editor/extensions/source_editor_extension_base';
+
+export class YamlEditorExtension extends SourceEditorExtension {
+  /**
+   * Extends the source editor with capabilities for yaml files.
+   *
+   * @param { Instance } instance Source Editor Instance
+   * @param { boolean } enableComments Convert model nodes with the comment
+   * pattern to comments?
+   * @param { string } highlightPath Add a line highlight to the
+   * node specified by this e.g. `"foo.bar[0]"`
+   * @param { * } model Any JS Object that will be stringified and used as the
+   * editor's value. Equivalent to using `setDataModel()`
+   * @param options SourceEditorExtension Options
+   */
+  constructor({
+    instance,
+    enableComments = false,
+    highlightPath = null,
+    model = null,
+    ...options
+  } = {}) {
+    super({
+      instance,
+      options: {
+        ...options,
+        enableComments,
+        highlightPath,
+      },
+    });
+
+    if (model) {
+      YamlEditorExtension.initFromModel(instance, model);
+    }
+
+    instance.onDidChangeModelContent(() => instance.onUpdate());
+  }
+
+  /**
+   * @private
+   */
+  static initFromModel(instance, model) {
+    const doc = new Document(model);
+    if (instance.options.enableComments) {
+      YamlEditorExtension.transformComments(doc);
+    }
+    instance.setValue(doc.toString());
+  }
+
+  /**
+   * @private
+   * This wraps long comments to a maximum line length of 80 chars.
+   *
+   * The `yaml` package does not currently wrap comments. This function
+   * is a local workaround and should be deprecated if
+   * https://github.com/eemeli/yaml/issues/322
+   * is resolved.
+   */
+  static wrapCommentString(string, level = 0) {
+    if (!string) {
+      return null;
+    }
+    if (level < 0 || Number.isNaN(parseInt(level, 10))) {
+      throw Error(`Invalid value "${level}" for variable \`level\``);
+    }
+    const maxLineWidth = 80;
+    const indentWidth = 2;
+    const commentMarkerWidth = '# '.length;
+    const maxLength = maxLineWidth - commentMarkerWidth - level * indentWidth;
+    const lines = [[]];
+    string.split(' ').forEach((word) => {
+      const currentLine = lines.length - 1;
+      if ([...lines[currentLine], word].join(' ').length <= maxLength) {
+        lines[currentLine].push(word);
+      } else {
+        lines.push([word]);
+      }
+    });
+    return lines.map((line) => ` ${line.join(' ')}`).join('\n');
+  }
+
+  /**
+   * @private
+   *
+   * This utilizes `yaml`'s `visit` function to transform nodes with a
+   * comment key pattern to actual comments.
+   *
+   * In Objects, a key of '#' will be converted to a comment at the top of a
+   * property. Any key following the pattern `#|<some key>` will be placed
+   * right before `<some key>`.
+   *
+   * In Arrays, any string that starts with #  (including the space), will
+   * be converted to a comment at the position it was in.
+   *
+   * @param { Document } doc
+   * @returns { Document }
+   */
+  static transformComments(doc) {
+    const getLevel = (path) => {
+      const { length } = path.filter((x) => isCollection(x));
+      return length ? length - 1 : 0;
+    };
+
+    visit(doc, {
+      Pair(_, pair, path) {
+        const key = pair.key.value;
+        // If the key is = '#', we add the value as a comment to the parent
+        // We can then remove the node.
+        if (key === '#') {
+          Object.assign(path[path.length - 1], {
+            commentBefore: YamlEditorExtension.wrapCommentString(pair.value.value, getLevel(path)),
+          });
+          return visit.REMOVE;
+        }
+        // If the key starts with `#|`, we want to add a comment to the
+        // corresponding property. We can then remove the node.
+        if (key.startsWith('#|')) {
+          const targetProperty = key.split('|')[1];
+          const target = findPair(path[path.length - 1].items, targetProperty);
+          if (target) {
+            target.key.commentBefore = YamlEditorExtension.wrapCommentString(
+              pair.value.value,
+              getLevel(path),
+            );
+          }
+          return visit.REMOVE;
+        }
+        return undefined; // If the node is not a comment, do nothing with it
+      },
+      // Sequence is basically an array
+      Seq(_, node, path) {
+        let comment = null;
+        const items = node.items.flatMap((child) => {
+          if (comment) {
+            Object.assign(child, { commentBefore: comment });
+            comment = null;
+          }
+          if (
+            isScalar(child) &&
+            child.value &&
+            child.value.startsWith &&
+            child.value.startsWith('#')
+          ) {
+            const commentValue = child.value.replace(/^#\s?/, '');
+            comment = YamlEditorExtension.wrapCommentString(commentValue, getLevel(path));
+            return [];
+          }
+          return child;
+        });
+        Object.assign(node, { items });
+        // Adding a comment in case the last one is a comment
+        if (comment) {
+          Object.assign(node, { comment });
+        }
+      },
+    });
+    return doc;
+  }
+
+  /**
+   * Get the editor's value parsed as a `Document` as defined by the `yaml`
+   * package
+   * @returns {Document}
+   */
+  getDoc() {
+    return parseDocument(this.getValue());
+  }
+
+  /**
+   * Accepts a `Document` as defined by the `yaml` package and
+   * sets the Editor's value to a stringified version of it.
+   * @param { Document } doc
+   */
+  setDoc(doc) {
+    if (this.options.enableComments) {
+      YamlEditorExtension.transformComments(doc);
+    }
+
+    if (!this.getValue()) {
+      this.setValue(doc.toString());
+    } else {
+      this.updateValue(doc.toString());
+    }
+  }
+
+  /**
+   * Returns the parsed value of the Editor's content as JS.
+   * @returns {*}
+   */
+  getDataModel() {
+    return this.getDoc().toJS();
+  }
+
+  /**
+   * Accepts any JS Object and sets the Editor's value to a stringified version
+   * of that value.
+   *
+   * @param value
+   */
+  setDataModel(value) {
+    this.setDoc(new Document(value));
+  }
+
+  /**
+   * Method to be executed when the Editor's <TextModel> was updated
+   */
+  onUpdate() {
+    if (this.options.highlightPath) {
+      this.highlight(this.options.highlightPath);
+    }
+  }
+
+  /**
+   * Set the editors content to the input without recreating the content model.
+   *
+   * @param blob
+   */
+  updateValue(blob) {
+    // Using applyEdits() instead of setValue() ensures that tokens such as
+    // highlighted lines aren't deleted/recreated which causes a flicker.
+    const model = this.getModel();
+    model.applyEdits([
+      {
+        // A nice improvement would be to replace getFullModelRange() with
+        // a range of the actual diff, avoiding re-formatting the document,
+        // but that's something for a later iteration.
+        range: model.getFullModelRange(),
+        text: blob,
+      },
+    ]);
+  }
+
+  /**
+   * Add a line highlight style to the node specified by the path.
+   *
+   * @param {string|null|false} path A path to a node of the Editor's value,
+   * e.g. `"foo.bar[0]"`. If the value is falsy, this will remove all
+   * highlights.
+   */
+  highlight(path) {
+    if (this.options.highlightPath === path) return;
+    if (!path) {
+      SourceEditorExtension.removeHighlights(this);
+    } else {
+      const res = this.locate(path);
+      SourceEditorExtension.highlightLines(this, res);
+    }
+    this.options.highlightPath = path || null;
+  }
+
+  /**
+   * Return the line numbers of a certain node identified by `path` within
+   * the yaml.
+   *
+   * @param {string} path A path to a node, eg. `foo.bar[0]`
+   * @returns {number[]} Array following the schema `[firstLine, lastLine]`
+   * (both inclusive)
+   *
+   * @throws {Error} Will throw if the path is not found inside the document
+   */
+  locate(path) {
+    if (!path) throw Error(`No path provided.`);
+    const blob = this.getValue();
+    const doc = parseDocument(blob);
+    const pathArray = toPath(path);
+
+    if (!doc.getIn(pathArray)) {
+      throw Error(`The node ${path} could not be found inside the document.`);
+    }
+
+    const parentNode = doc.getIn(pathArray.slice(0, pathArray.length - 1));
+    let startChar;
+    let endChar;
+    if (isMap(parentNode)) {
+      const node = parentNode.items.find(
+        (item) => item.key.value === pathArray[pathArray.length - 1],
+      );
+      [startChar] = node.key.range;
+      [, , endChar] = node.value.range;
+    } else {
+      const node = doc.getIn(pathArray);
+      [startChar, , endChar] = node.range;
+    }
+    const startSlice = blob.slice(0, startChar);
+    const endSlice = blob.slice(0, endChar);
+    const startLine = (startSlice.match(/\n/g) || []).length + 1;
+    const endLine = (endSlice.match(/\n/g) || []).length;
+    return [startLine, endLine];
+  }
+}

package.json

@@ -199,7 +199,8 @@
     "webpack-cli": "^3.3.12",
     "webpack-stats-plugin": "^0.3.1",
     "worker-loader": "^2.0.0",
-    "xterm": "3.14.5"
+    "xterm": "3.14.5",
+    "yaml": "^2.0.0-8"
   },
   "devDependencies": {
     "@babel/plugin-transform-modules-commonjs": "^7.10.1",

spec/frontend/editor/source_editor_extension_base_spec.js

@@ -148,7 +148,10 @@ describe('The basis for an Source Editor extension', () => {
       revealLineInCenter: revealSpy,
       deltaDecorations: decorationsSpy,
     };
-    const defaultDecorationOptions = { isWholeLine: true, className: 'active-line-text' };
+    const defaultDecorationOptions = {
+      isWholeLine: true,
+      className: 'active-line-text',
+    };
 
     useFakeRequestAnimationFrame();
 
@@ -157,18 +160,22 @@ describe('The basis for an Source Editor extension', () => {
     });
 
     it.each`
-      desc                                               | hash         | shouldReveal | expectedRange
-      ${'properly decorates a single line'}              | ${'#L10'}    | ${true}      | ${[10, 1, 10, 1]}
-      ${'properly decorates multiple lines'}             | ${'#L7-42'}  | ${true}      | ${[7, 1, 42, 1]}
-      ${'correctly highlights if lines are reversed'}    | ${'#L42-7'}  | ${true}      | ${[7, 1, 42, 1]}
-      ${'highlights one line if start/end are the same'} | ${'#L7-7'}   | ${true}      | ${[7, 1, 7, 1]}
-      ${'does not highlight if there is no hash'}        | ${''}        | ${false}     | ${null}
-      ${'does not highlight if the hash is undefined'}   | ${undefined} | ${false}     | ${null}
-      ${'does not highlight if hash is incomplete 1'}    | ${'#L'}      | ${false}     | ${null}
-      ${'does not highlight if hash is incomplete 2'}    | ${'#L-'}     | ${false}     | ${null}
-    `('$desc', ({ hash, shouldReveal, expectedRange } = {}) => {
+      desc                                                  | hash         | bounds          | shouldReveal | expectedRange
+      ${'properly decorates a single line'}                 | ${'#L10'}    | ${undefined}    | ${true}      | ${[10, 1, 10, 1]}
+      ${'properly decorates multiple lines'}                | ${'#L7-42'}  | ${undefined}    | ${true}      | ${[7, 1, 42, 1]}
+      ${'correctly highlights if lines are reversed'}       | ${'#L42-7'}  | ${undefined}    | ${true}      | ${[7, 1, 42, 1]}
+      ${'highlights one line if start/end are the same'}    | ${'#L7-7'}   | ${undefined}    | ${true}      | ${[7, 1, 7, 1]}
+      ${'does not highlight if there is no hash'}           | ${''}        | ${undefined}    | ${false}     | ${null}
+      ${'does not highlight if the hash is undefined'}      | ${undefined} | ${undefined}    | ${false}     | ${null}
+      ${'does not highlight if hash is incomplete 1'}       | ${'#L'}      | ${undefined}    | ${false}     | ${null}
+      ${'does not highlight if hash is incomplete 2'}       | ${'#L-'}     | ${undefined}    | ${false}     | ${null}
+      ${'highlights lines if bounds are passed'}            | ${undefined} | ${[17, 42]}     | ${true}      | ${[17, 1, 42, 1]}
+      ${'highlights one line if bounds has a single value'} | ${undefined} | ${[17]}         | ${true}      | ${[17, 1, 17, 1]}
+      ${'does not highlight if bounds is invalid'}          | ${undefined} | ${[Number.NaN]} | ${false}     | ${null}
+      ${'uses bounds if both hash and bounds exist'}        | ${'#L7-42'}  | ${[3, 5]}       | ${true}      | ${[3, 1, 5, 1]}
+    `('$desc', ({ hash, bounds, shouldReveal, expectedRange } = {}) => {
       window.location.hash = hash;
-      SourceEditorExtension.highlightLines(instance);
+      SourceEditorExtension.highlightLines(instance, bounds);
       if (!shouldReveal) {
         expect(revealSpy).not.toHaveBeenCalled();
         expect(decorationsSpy).not.toHaveBeenCalled();
@@ -193,6 +200,43 @@ describe('The basis for an Source Editor extension', () => {
       SourceEditorExtension.highlightLines(instance);
       expect(instance.lineDecorations).toBe('foo');
     });
+
+    it('replaces existing line highlights', () => {
+      const oldLineDecorations = [
+        {
+          range: new Range(1, 1, 20, 1),
+          options: { isWholeLine: true, className: 'active-line-text' },
+        },
+      ];
+      const newLineDecorations = [
+        {
+          range: new Range(7, 1, 10, 1),
+          options: { isWholeLine: true, className: 'active-line-text' },
+        },
+      ];
+      instance.lineDecorations = oldLineDecorations;
+      SourceEditorExtension.highlightLines(instance, [7, 10]);
+      expect(decorationsSpy).toHaveBeenCalledWith(oldLineDecorations, newLineDecorations);
+    });
+  });
+
+  describe('removeHighlights', () => {
+    const decorationsSpy = jest.fn();
+    const lineDecorations = [
+      {
+        range: new Range(1, 1, 20, 1),
+        options: { isWholeLine: true, className: 'active-line-text' },
+      },
+    ];
+    const instance = {
+      deltaDecorations: decorationsSpy,
+      lineDecorations,
+    };
+
+    it('removes all existing decorations', () => {
+      SourceEditorExtension.removeHighlights(instance);
+      expect(decorationsSpy).toHaveBeenCalledWith(lineDecorations, []);
+    });
   });
 
   describe('setupLineLinking', () => {

yarn.lock

@@ -12806,6 +12806,11 @@ yaml@^1.10.0:
   resolved "https://registry.yarnpkg.com/yaml/-/yaml-1.10.2.tgz#2301c5ffbf12b467de8da2333a459e29e7920e4b"
   integrity sha512-r3vXyErRCYJ7wg28yvBY5VSoAF8ZvlcW9/BwUzEtUsjvX/DKs24dIkuwjtuprwJJHsbyUbLApepYTR1BN4uHrg==
 
+yaml@^2.0.0-8:
+  version "2.0.0-8"
+  resolved "https://registry.yarnpkg.com/yaml/-/yaml-2.0.0-8.tgz#226365f0d804ba7fb8cc2b527a00a7a4a3d8ea5f"
+  integrity sha512-QaYgJZMfWD6fKN/EYMk6w1oLWPCr1xj9QaPSZW5qkDb3y8nGCXhy2Ono+AF4F+CSL/vGcqswcAT0BaS//pgD2A==
+
 yargs-parser@^13.1.2:
   version "13.1.2"
   resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-13.1.2.tgz#130f09702ebaeef2650d54ce6e3e5706f7a4fb38"